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Case Study

In order to reduce replacement costs and failures, a mid-size Mid-Atlantic utility engaged Xylem for help developing a machine learning approach to building a focused and cost-effective pipeline renewal strategy.

A mid-sized Mid-Atlantic utility with a reputation for taking a proactive and focused approach to continuously improving service reliability to their 270,000 customers was facing all too common situation. More than 1,000 miles of water mains across their system, with an average age of about 50 years. This had led to an increase in water main breaks, and so they started seeking innovative strategies that would improve service reliability while minimizing repair and replacement costs.

THE CHALLENGE

With water main breaks increasing, the customers served by the utility were challenged with unpredictable service outages and costly repairs as well as highly disruptive road closures. They desired to take a more proactive approach to prevent main breaks and improve their customer level of service (LoS) by focusing on the pipes that needed the greatest attention.

Previous experience in working with Xylem to manage their PCCP (prestressed concrete cylinder pipe) inventory led the utility to seek out a better replacement prioritization strategy than traditional techniques such as age and break history.

What solutions did Xylem and the utility come up with to solve this challenge? Find out and explore the results we achieved together by downloading the full case study below.

Project Highlights

Will help the utility lower their annual costs related to pipeline replacement from $90 million to just $20 million while achieving a dramatic four-fold reduction in failures.

Developed a plan to reduce customer outages and improve service reliability, while cutting replacement spending by over 70% compared to other prioritization methods.

Developed a real-time, field mobile tracking application to improve break record accuracy that reduces labor time required to update their Computerized maintenance management system (CMMS) and their geographic information system (GIS), as well as improve the output of the AI model

Services Provided

• Pipeline failure and risk analysis
• Mobile field data collection application
• Data integration with the utility’s existing systems

Case Study

In order to maximize their existing capital assets, reducing overflows and optimizing overall operation efficiency, the Metropolitan Sewer District of Greater Cincinnati (MSD) engaged Xylem in utilizing BLU-X, a drainage network optimization solution that uses a real-time decision support system consisting of smart sensors and actuators that track conveyance capacity.

Cincinnati’s sewers discharge an average of 11.5 billion gallons of combined sewage every year into the Ohio River and its tributary streams within Cincinnati’s urban watershed.

In 2002, the EPA entered into a federal consent decree with MSD, mandating the elimination of sanitary sewer overflows and significant mitigation of combined sewer overflows into receiving waterways. Engineers estimated the cost to mitigate the sewer overflows at $3.1 billion, an unacceptable capital expense to pass along to MSD’s customers.

THE CHALLENGE

Recognizing the generally inadequate stormwater management capabilities of their existing combined sewer system, MSD prepared a comprehensive wet weather improvement plan. MSD recognized that full sewer separation and deep tunnel construction are massive capital investments that have a very low return on investment because they create only episodic benefits during peak flow events and are single-use assets with little additional community wealth creation.

Instead, MSD’s objective was to maximize existing capital assets — such as sewer interceptors, storage and treatment facilities, and pump-stations — to reduce overflows and gain system-wide benefits through advanced control logic that will optimally operate MSD’s urban watershed.

What solutions did Xylem and MSD come up with to solve this challenge? Find out and explore the results we achieved together by downloading the full case study below.

Project Highlights

Overflow volumes reduced by 247 million gallons annually

More than a 90% reduction in cost compared to initial capital work estimated at $38 million

CSO mitigation achieved at a price of less than$0.01/gallon

Services Provided

• BLU-X real-time decision support system (RT-DSS) to manage storage and conveyance
• RT-DSS integrated into MSD’s existing SCADA and IT networks
• All sensor data presented on one unified platform

Case Study

In order to get a better understanding of the infiltration and inflow into their newly separated sanitary sewers, Grand Rapids engaged Xylem in utilizing BLU-X, a real-time decision support system consisting of smart sensors and actuators that track conveyance capacity.

Grand Rapids, MI is a community that has garnered accolades in the clean water industry for taking significant proactive steps to improve its sewer system. In the early 1990s, “River City” took the initiative to invest in transforming its collection system from a combined sewer system to separate storm and sanitary sewers. By moving from a single pipe for both stormwater and wastewater conveyance to separate pipes, the City avoided the introduction of sewage into its waterways, reducing overflows and subsequent pollution into the landmark Grand River that flows to Lake Michigan 40 miles downstream.

THE CHALLENGE

After nearly 25 years, Grand Rapids finished retrofitting its combined sewer overflow system to a separate sanitary and stormwater system, completing its long-term control plan (LTCP) in 2015. But now, the City needed to get a better understanding of the infiltration and inflow into these newly separated sanitary sewers to ensure compliance with a mandate from the Michigan Department of Environmental Quality (DEQ). This mandate allowed them zero overflow events of any kind, except as part of a wet weather event of a magnitude in excess of a 24-hour, 25-year storm.

For compliance purposes, the City needed analytic data to certify performance and understand how the system behaved during a wide variety of wet and dry weather conditions. While gathering this information, the City was also presented with a hydraulic report stating that areas of the community were experiencing excessive surcharging and flooding. They suspected otherwise, but needed proof to answer regulators, as mitigation to eliminate the surcharging and flooding was estimated to cost much as $1 billion; a capital expense the city could ill afford.

What solutions did Xylem and Grand Rapids come up with to solve this challenge? Find out and explore the results we achieved together by downloading the full case study below.

Project Highlights

Data demonstrated that the infiltration and inflow problem could be solved for $30-50 million as opposed to the original $1 billion estimate

Real-time decision support system brought in to help the Environmental Services Department for the sanitary system separation

City has expanded the sensor network to more parts of the system

Services Provided

• BLU-X real-time decision support system (RT-DSS) deployed to help characterize infiltration and inflow performance on sanitary lines
• All sensor data presented on one unified platform
• Integration into Grand Rapids’s existing IT networks

Utilities can save their communities substantial amounts of money, reduce the need for unaffordable rate increases or financing arrangements, and improve the environmental sustainability of their operations – all while maintaining and enhancing system control.

Around the world, critical valves are in poor repair, or even inoperable. When critical valves fail, managers have effectively lost control of their system, increasing vulnerability to water main breaks or any other system hazard. Once valves have failed, utilities have traditionally sought to replace them, often at great cost, both in terms of time and expense.

But what if there were another way? It turns out there is a far more economical, less risky, and more sustainable option: preventative maintenance, repair, and rehabilitation. High performing utilities are turning away from the wasteful practice of replacing valves that can be restored to full function, instead engaging experts in asset renewal to extend the life of those assets at a substantially lower cost.

This white paper will highlight:

  • identifying the true cost of large valve replacements
  • understanding the cost savings of a repair vs replace strategy
  • the benefits of performing routine critical valve assessments
  • what to look for in a valve assessment partner

With advancements in technology and a willingness to develop proactive pipeline integrity programs, utilities can successfully reduce failures, mitigate risk, reduce capital expenditures, and increase confidence in the overall operation of their force mains.

New standards of best practice for force main management involve a variety of methods and technologies to provide data and information with which to make decisions. Utilities can now often perform a detailed condition assessment while the force main remains in service.

There is no “one-size-fits-all” way of assessing force mains. Any approach should be tailored to risk tolerance, material, diameter and past failure history. Savvy utility managers are turning to programs that reduce damage to assets, prioritize investment to minimize community impact of asset failure, and reduce the consequence of failure by enabling system control.

This white paper will highlight:

  • how to develop a risk-based program
  • the most common modes of failure for force mains
  • how to define which of the three approaches to proactively assessing force mains best fits your goals and risk-tolerance
  • how utilities are finding success using these approaches to: prevent failures, reduce capital expenditures, mitigate risk, optimize budget allocation, and increase confidence and level of service.

Case Study

In order to avoid the cost associated with large valve replacement, the city of Grand Rapids engaged Xylem to assess the true condition of 20 large valves and determine if they could be rehabilitated or repaired instead.

The City of Grand Rapids is the second largest water system in Michigan and delivers clean drinking water to the Grand Rapids area using Lake Michigan as its water source. The Grand Rapids Water System operates about 1,250 miles of pipelines, 31,000 system valves, and over 1,300 large system valves (16 inches and larger). Over the last few years, the operation and maintenance of the large valves had declined due to focus being placed on other critical priorities. Without a consistent exercise routine for critical valves, the utility found that many of these valves were inoperable and, as a result, began to seek funding for valve replacements.

THE CHALLENGE

Grand Rapids was aware of a long segment of transmission line that could not be isolated due to inoperable valves. To regain control of the line, the City replaced five large valves at an average cost of $125,000 per valve, each taking an average of one week to replace. This amount of work and cost was a wake-up call that compelled Grand Rapids to find alternate methods of rehabilitating their valve assets.

Xylem’s experience has shown that on average, 60 percent of valves in a water system are operable, meaning that 40 percent are either inoperable, not locatable, or in the wrong position. Statistically, this meant that with 1,300 valves in Grand Rapids’ system, around 500 of them could have some sort of issue. With limited information on which ones required attention and a limited capital budget for asset replacement, the City would need a more focused approach help them make repair or remediation decisions.

What solutions did Xylem and Grand Rapids come up with to solve this challenge? Find out and explore the results we achieved together by downloading the full case study below.

Project Highlights

The City saved more than $800k by assessing and repairing infrastructure rather than replacing – a cost savings of over 90%

8 critical valves restored to full operability for less than the cost of replacing just one valve

60% of the assessed valves were working properly, allowing operational expenditures to be allocated elsewhere

Services Provided

• Valve assessment – assessed 20 large valves in the transmission system
• Valve repair – repaired and restored eight critical valves to full operability
• Valve rehabilitation – rehabilited one inoperable 36″ gate valve

pipe_diver

On Thursday May 17, thought-leaders, leading utilities, and other industry experts, came together for Xylem’s Modernizing Water Infrastructure Workshop in Laurel, MD. Like Infrastructure Week, the event served as a platform for innovators to connect, discuss, and inspire water industry professionals to solve the problems associated with managing water infrastructure. If you were unable to attend, here are some of the highlights of the day.

From Manure To Modern

The morning session focused on utilities, and began with a keynote presentation from industry visionary, George Hawkins, who provided an energetic analogy on how the manure crisis of the 1800s compares to our current water crisis. While the common person only saw the problem of horse manure, the engineers of the 1800s saw the potential for change and created the car, which eliminated the problem while increasing productivity and reducing costs. That’s what we, as an industry, need to focus on as we modernize water infrastructure — seeing the potential for greatness and improvement through innovation.

Hawkins went on to discuss how we report efficiency. If everything is measured in a productivity approach, seeking additional funding becomes easier. Money has gone farther than ever before in the water infrastructure industry because of the advancements in technology that allow us to work more efficiently and accurately. People are prepared to invest in something that matters to them, especially when they understand that the current monies are going further, and you can prove it. Listen to part of Hawkins’ presentation:

100 Years of Continuous Improvement

Following Hawkins’ passionate keynote address, we heard from Glen Diaz, Division Manager of Water/Wastewater Systems Assessment at WSSC. As WSSC (Washington Suburban Sanitary Commission) celebrates their 100-year anniversary, Diaz reflected on the advancements in technology through the years.

Even in the past 10 years, things have greatly improved in the water industry. Diaz cited the 66” water main break in Bethesda, MD in 2008 and how current technology can aid in preventing future incidents. Diaz went on to discuss how most PCCP failures are due to broken wires and how noisy pipes are typically problem pipes.

However, now, WSSC workers receive mobile alerts, through the implementation of Pure Technologies AFO system, as soon as wire breaks occur so they can address any cause for concern. This system has already helped WSSC avert 20 failure events to date, a $21 million dollar savings on the conservative side! See Diaz’s presentation here:

With Challenge, Comes Major Opportunity

After hearing from WSSC, we heard from Jody Caldwell, Asset Management Director for Great Lakes Water Authority (GLWA), on building an asset management program from the (under) ground up.

Caldwell began with an overview of some of the organizational challenges GLWA is experiencing being a relatively new utility. He talked about the process GLWA went through putting together a 10-year strategic roadmap focused on continuous improvement to overcome the challenges and build a utility for the future. Caldwell went on to discuss GLWA’s pipeline risk management strategy, which uses a quantitative, risk-based analysis to drive decisions. This tiered approach allows them to easily calculate their risk return on investment and ultimately, become a best-in-class pipeline management system. Catch the end of Caldwell’s presentation, as well as the Q&A session.

Extreme Preparation for Extreme Weather

After a brief networking break, there was a roundtable discussion that focused on how leading utilities dealt with the extreme weather conditions this past January. The roundtable featured (from left to right) Joseph Mantua, Deputy General Manager Operations at WSSC; Carlos A. Espinosa, Chief of the Office Of Asset Management at Baltimore City Department of Public Works; and Buddy Morgan, General Manager at Montgomery Water Works (Alabama). Who said the South doesn’t experience cold weather.

The discussion began with the question, “Were there particular pipe materials you found to be problematic during the extreme winter, and if so, what were they?” For the City of Montgomery, AL, cast iron mains had the most problems. Baltimore City was no different, reporting that 98% of the water main breaks were in cast iron pipes, the majority of which were 12” or smaller. WSSC confirmed the cast iron trend, with the majority of breaks occurring in 6 or 8 inch diameter pipes.

In order to prepare for next winter, the utilities agreed for the need to ensure that all their equipment is in working order ahead of time, and have conversations with their crews and contractors to make sure they’re prepared to respond, and recognize the need for additional support services and how to best utilize them. Additionally, the panel agreed that social media played a crucial role in real-time communications with customers, aiding them in being proactive with the media, and helping to communicate status updates. Watch the beginning portion of the roundtable discussion:

The discussion moved on to how to keep employees engaged during extreme weather conditions. Aside from the generous overtime benefits, WSSC brought hot meals to workers, while Alabama Water Works limited hours per week to 65 with 24 hours off before coming back. They also held celebratory cookouts once the weather warmed up.

Be Best-In-Class

After lunch, the afternoon sessions focused on technologies and management best practices. Pure’s very own Mike Higgins, Senior Vice President, Americas, talked about buried infrastructure philosophies utilities can use to manage their most valuable assets. Mike kicked-off his presentation by sharing statistics from the 2017 Infrastructure Report Card from the American Society of Civil Engineers (ASCE).

Following these eye-opening numbers, Higgins shared his insights on success for professionals in the water industry.
Key questions utilities need to answer include:

  • Why do you want to assess your pipeline?
  • What are the goals for your project or program?

 

Typically, the answers should focus on one or more of the following areas:

1) Averting pipeline failure
2) Reducing pipeline risk
3) Extending the life of an asset
4) Increasing sustainability
5) Optimizing CAPEX/TOTEX (capital/total expenditure)

Higgins then shared his secret recipe for the 10 key ingredients to be a best-in-class utility:
1) Focus on operations excellence
2) Coordinate with all key stakeholders
3) Perform necessary Public Relations
4) Create a clearly defined team across departments and disciplines
5) Always aspire towards total pipeline management
6) Prepare for emergencies, they will occur
7) Be opportunistic
8) Continue to innovate
9) Understand limitations of innovative approaches
10) Keep your boots on the ground (maximize the amount of inspected pipe)
 
He concluded his presentation talking about the importance of monitoring key performance indicators (KPIs) and keeping senior leadership engaged. Watch Higgins’ presentation:

The 4th Industrial Revolution

Richard Loeffler IV, Client Solutions Architect at Emnet, then reminded us that the number one criteria for where cities locate is the access to water. Loeffler also stated that we are in the midst of a 4th industrial revolution—IoT (Internet of Things) is changing the way we live, work, and play, and is transforming the fundamental economic cost structure of water and related civic works.

He used the example of South Bend, IN, to illustrate just how effective IoT and RTDSS (real-time decision support systems) can be. Ultimately, it’s all about environmental stewardship — it’s not just about saving money, but about doing the right thing for the world that we live in. View Loeffler’s presentation:

Smart Water

Following Loeffler’s informative presentation, Bridget Berardinelli, VP Product Management And Continuous Improvement for Xylem, stated how smart meters and applying analytics can help utilities generate real results. Berardinelli began by explaining how Sensus develops advanced technology solutions that enable the intelligent use of critical resources.

She covered Advanced Metering Infrastructure (AMI) and explained how to leverage it in order to increase operational efficiencies and improve scalability and flexibility. By delivering machine learning and analytics using a programmatic approach, Sensus is able to inform operational interventions that transform how water utilities operate. View her presentation:

Our Newest Solution

Concluding Berardinelli’s presentation, we heard from Pure Technologies Area Regional Manager, Susan Donnally, on how to manage large diameter water transmission mains. She began her presentation with a discussion on pipeline risk prioritization, stating that using data to drive decisions is a quintessential part of moving towards a proactive asset management approach. She then dove into why pipes fail; noting that age alone is a poor indicator of pipe condition. While there is no singular technology that can identify all of the indicators of pipe deterioration, a holistic, risk-based approach can help.

Donnally then moved on to highlight some of Pure’s latest technology innovations:

  • SmartBall® – in addition to leak and gas pocket detection, the tool now provides mapping, which combines data collected during an inspection with known, aboveground locations and pipeline drawings to create a field-generated GIS map of a pipeline.
  • PipeDiver® – Pure’s free-swimming condition assessment tool is now available with video and can easily correlate the data you’re getting from electromagnetics with actual footage.

 

Additionally, Donnally had a huge reveal! She introduced Pure’s newest PipeDiver solution, the PipeDiver UltraTM (currently in the beta testing phase with a couple of clients), which features high-resolution wall condition information for metallic pipes, such as cast iron, ductile iron, and steel, and is as easy to deploy as the existing PipeDiver. Watch her presentation:

You’re Not Going to Start with Perfection

Vice President of PureAnalytics, Travis Wagner, gave the final presentation of the day on managing distribution systems.

He truly engaged the audience by asking attendees to raise their hands if:

  • They saw a need or value in a pipeline renewal program
  • They agreed that a 10-20% efficiency in renewal programs is OK
  • They thought customer affordability was an issue
  • They had trouble with retirements and recruiting

 
Not surprisingly, most hands were raised! From there, Wagner went on to urge everyone to update their approach.

Utilities need to start asking themselves the following questions:

  • What is the current state of my assets?
  • What is my required level of service?
  • Which assets are critical to sustained performance?
  • What are my best O&M and CIP investment strategies?
  • What is my best long-term funding strategy?

 
Wagner concluded this portion of the presentation with a quote that all utilities should follow: “You’re not going to start with perfection, the goal is to build toward becoming better.”

Next, Wagner moved on to discuss risk management, consequence probability analysis, data collection, and risk mitigation. It was truly an eye-opening presentation:

The day concluded with demonstrations of all the latest technology available to utilities, including a 108” PipeDiver, SoundPrint® AFO system, Sensus meters, Visenti software demos, not to mention some great networking.

Want to learn more about our Modernizing Water Infrastructure Workshop? Check out #H2018Workshop on Facebook, LinkedIn, and Twitter.

 

Airfield location meant inspection scheduling was booked five months in advance.

Water main inspection to manage the critical assets for the Vancouver International Airport takes months of proactive planning, safety and scheduling.

In the management of a major international airport like Vancouver International Airport (YVR), Vancouver Airport Authority (VAA) operation officials inevitably face a number of unique challenges. Compounding the challenges is the fact that the airport runs as a mini-municipality because of its size and island location within the jurisdiction of the City of Richmond.

When carrying out a water main inspection in an airfield location, strict rules apply to how you operate in that area. A well-executed inspection requires a dedication to planning, safety, and scheduling.

Being an airfield location, a lot of detailed planning went into managing this South Runway Watermain Inspection. We stuck to the schedule, met all milestones, and were extremely pleased with the execution of the safety plan, which was critical in this restricted environment.” Stephen Little, Technical Specialist-Mechanical, Vancouver International Airport.

The water line provides an important service to South Terminal and leased buildings.

Project background

Canada’s second busiest airport, YVR, served 24.2 million passengers in 2017. Last year, VAA engaged Pure Technologies to perform a Sahara® leak and air pocket detection inspection on the South Runway Watermain (SRW). Built in 1966, the SRW is a 350mm water main constructed of asbestos cement that runs from the Airport Field Bulk Water Meter to the South Domestic Terminal for approximately 870m (2850 ft.).

The water line provides an important service to both the South Terminal and leased airport buildings, which include a busy McDonald’s, the Floatplane Terminal, Flying Beaver Bar & Grill and multiple aircraft maintenance facilities. The line also runs along the main airfield, and across some taxiing areas, driving home the point that failure is not an option.

The airport receives water from the City of Richmond, which was also keenly interested in the inspection planning, technology and the outcome.

A multi-purpose inspection

The main purpose of the survey was to assess the condition of the main to identify and accurately locate any leaks or air pockets using the acoustic capabilities of the Sahara leak detection tool. VAA wanted a visual take on the inside of the pipe using the video capabilities of the tool’s CCTV camera. In addition, VAA also wanted to map the bends in the line and take GPS coordinates at select points to update alignment plans.

Another important purpose of the inspection was to eliminate water loss at the airport, a goal initiated by management as part of a proactive environmental program to conserve water. Management wanted to locate areas of potential water loss in their system to help achieve their water reduction targets of 30 percent by 2020.

YVR receives water from the City of Richmond via several bulk meter locations. From here, VAA distributes the water throughout Sea Island. The presence of leaks would have an adverse effect on the airport reaching its water reduction targets.

Tethered Sahara tool is propelled by the product flow and features inline video to observe internal pipe conditions.

Sahara leak detection platform selected

Pure recommended the Sahara leak detection platform for its ability to provide same-day results, and to locate small leaks with sub-meter accuracy. The tethered tool is propelled by a small parachute inflated by the product flow.

The Sahara platform also features inline video that allows operators to observe internal pipe conditions, and in many instances, identify the type of leak and other details helpful for planning a repair before excavating.

 Although this first project was limited in scope and budget, because of the criticality of the line, both Pure and VAA put extra care and planning into efforts to ensure a relatively effortless access and retrieval of the condition assessment tool.

The City of Richmond assisted by removing their aging water meter and installing the flange supplied by the Sahara team for the launch of the tool. The City of Richmond then took the inspection opportunity to upgrade the old meter to a newer ultrasonic model.

Airfield location meant maintaining inspection schedule was critical  

As the line was located in the airfield, maintaining the inspection schedule was critical. Security escorts were required at all times for non-YVR employees, which meant scheduling for the project was booked nearly five months in advance.

As well, the inspection was a multi-jurisdictional project, as the pipeline was owned by both the City of Richmond and VAA, requiring close collaboration between all parties. Pure inserted the tool via the City of Richmond’s water meter (in the airfield) and inspected the downstream water main (owned by VAA).

“The South Runway Watermain inspection project was a good opportunity to trial and gain better understanding of the inspection technology. It also allowed us to get a level of comfort in order to identify other areas where we can apply it,” said Little. “Our comfort how well the inspection went is an incentive for us to explore more non-destructive inspection methods.”

The adaptable design of the Sahara tool allowed for a horizontal insertion at the water meter chamber. (Vertical insertion is the more common method for inserting the tool.)

Inspection results

The adaptable design of the Sahara tool allowed for a horizontal insertion (vertical is more common insertion method) at the water meter chamber and the inspection was completed under live conditions without disruption to service, using the water meter bypass and downstream fire hydrants.

In a single day, the Sahara crew inserted the tethered tool through the water meter chamber, inspected approximately 870 meters (2850 feet) and determined the pipeline alignment with all bends and 100-meter intervals marked. In conjunction with the inspection, VAA and the City of Richmond were able to upgrade the old water meter to an ultrasonic unit, a bonus to the inspection goals.

In the end, zero (0) leaks and zero (0) air pockets were identified during the inspection, and CCTV showed some small tuberculation on the metallic bends. Although VAA recognized no immediate concerns, the Airport Authority now knows the correct updated line location and the overall condition of their assets.

Overall, a great success for a pilot project.

 

A leak represents not only water loss, but can indicate the potential for pipeline failure.

How proactive utilities are taking the gamble out of finding leaks in order to mitigate failure risk

It takes a lot more than luck and traditional acoustic correlation methods to locate a suspected leak on large critical mains. Not all leaks are obvious, and some leaks can seep for years without visibly surfacing, putting utilities at risk for catastrophic failure.

That is why a proactive leak detection strategy plays such an important role in any asset management program. It allows utilities to obtain the general condition of their mains, since a leak not only represents a real water loss, but can also indicate the potential for pipeline failure.

Recently two water operators — The City of Vancouver, B.C. and The City of Norman, Texas— took measures to mitigate failure risks by implementing a leak detection program for their transmission networks. The utilities deployed various inline leak detection technologies, dependent on such factors as pipe diameter, material, access point availability, and operational constraints.

Acoustic intensity of anomaly and actual leak located

Left: Acoustic intensity of anomaly.   Right: Actual leak located

Inline technologies for leak detection

Inline leak detection technologies use non-destructive methods in which acoustic sensors are inserted into a pressurized pipeline. The “hissing” sound or vibration resulting from a leak in a pipe transmits an acoustic signal collected by the sensor when passing the leak site. The amplitude and frequency of the sound depends on the pipe material and internal pressure, and is easy to distinguish from other pipeline sounds.

Pure Technologies has developed two inline leak detection platforms for large-diameter pipelines of all materials: Sahara® (with a tethered sensor) and SmartBall® (a free-swimming tool).  Both tools are equipped with a sensitive acoustic sensor that can locate very small leaks (as small as 0.1 l/min) with high location accuracy.

SmartBall inside a pipe

The SmartBall tool can be launched while the main remains in operation, limiting disruption to service.

SmartBall leak detection technology

The SmartBall platform is an innovative technique to identify leaks and gas pockets in large-diameter pipelines while the line remains in service, minimizing disruption. The free-swimming ball contains a sophisticated leak detection circuitry and is released untethered into the water flow often through an air valve or hydrant (any 100mm opening). The SmartBall follows the water flow and is tracked by surface mounted sensors as it rolls through the pipe making a continuous recording of the acoustic activity in the pipeline. At a downstream location, the ball rolls into the retrieval device and is extracted from the pipe. The data is then evaluated to report the presence of leaks and gas pockets.

Since the SmartBall is propelled by the water flow, it can be used to survey the subject main for long distances (battery life up to 20 hours) in one deployment. As a result, modifications to the main are significantly reduced.

The tethered Sahara platform provides acoustic data on the presences of leaks and gas pockets and has the ability to map the pipeline alignment.

Tethered Sahara inspection platform

Utilities have long relied on the Sahara leak detection platform for speed, accuracy and real-time results.

The tethered platform identifies leaks and gas pockets by providing acoustic data on the presence of leaks for distances up to 1,800 meters (6,000 feet). The tool also has the ability for mapping the pipeline alignment, and is equipped with CCTV, adding an assessment.

The tool can be inserted into an active pipeline, through almost any tap two (2) inches and greater. As the Sahara tool enters the pipe, the flow velocity of the water inflates a small parachute, which pulls the tool through the pipe, with the probe lighting the way, highlighting any visual defects in the pipeline.

If the Sahara tool encounters any acoustic events – such as a leak – the operator can stop the tool at the exact point of the leak. At the same time, an above ground operator locates the sensor, marking the exact leak location within plus or minus 0.5 meters (18 inches). This enables users to know in real time where leaks are located.

The SmartBall tool was successfully retrieved with the acoustic data intact.

City of Vancouver SmartBall inspection

In March 2016, the City of Vancouver retained the services of Pure Technologies to perform a condition assessment of the Powell-Clark Feeder Main. The pipeline is comprised of concrete cylinder pipe (PCCP/BWP), ranging from 750 to 900m in diameter, installed in 1986-87.

In addition to providing an earlier PipeDiver® electromagnetic inspection to identify broken prestressing wire wraps on the main, Pure Technologies also performed a SmartBall inspection to identify and locate leaks and pockets of trapped gas along the line.

The SmartBall tool was inserted into the pipeline through a flange access and acoustic data was collected and recorded as the tool traversed the pipeline. At a distance of 5.8 kilometers, (470 meters from the end of the inspection run), the tool stopped, which was confirmed by the live tracking software. By analyzing data from the earlier PipeDiver EM inspection, Pure determined that unknown debris likely lodged the SmartBall tool.

The City excavated and modified a tap to allow Pure to access the pipeline with a submersible ROV (equipped with a camera) to retrieve the SmartBall tool and examine the debris, which turned out to be an old tool cart. The cart and SmartBall tool were extracted, and the data considered valid.

Analysis indicated three (3) anomalies characteristic of leaks and zero (0) pockets of trapped gas. Two (2) instances of entrained air were identified as migratory acoustic anomalies, and flagged for future inspection, as they may develop new pockets of trapped air.

When combined with the results from the EM inspection, the condition data will be used as part of the City of Vancouver’s asset management initiative and allow for proactive measures in the management of their infrastructure.

Sahara inspection for City of Norman, Texas 

In December 2016, Pure Technologies performed a leak detection survey on the 30-inch Robinson Street Replacement Water Main (RSRWM) for McKee Utility Contractors (McKee).  The RSRWM is owned and operated by the City of Norman, Oklahoma.

McKee suspected a leak on the pipeline, as the RSRWM was failing to hold pressure during the 150 psi hydrostatic pressure test.  As a result, McKee requested that Pure Technologies inspect 4,248 feet of the RSRWM and pinpoint any leaks in the inspected section.

The Sahara platform was selected for its ability to provide same-day results, and to accurately locate small leaks with sub-meter accuracy. The tethered tool is propelled by a small parachute inflated by the product flow, requiring a flow velocity as little as one foot per second to progress through a water main.

Because the pipeline was not yet in service, the flow was generated with a city connection pushing water into the main, and a 12-inch blow-off spewing it out. The Sahara audio-visual (AV) sensor was deployed to the endpoint using the flow velocity provided by the blow-off.

After the leak was located and marked above ground, McKee quickly excavated around the butterfly valve, tightened the bolts and eliminated the leak on the same day.

Two leaks detected, located and repaired

As a result of the survey, 4,294 feet of the RSRWM was inspected, with two leaks located.

Leak 1 was located 1000 feet from the first insertion. Video from the Sahara tool showed that the leak was located on the mechanical joint securing the inline butterfly valve to the pipeline. The Sahara team located the leak, and marked it above ground and McKee was able to start excavating immediately. After quickly excavating the butterfly valve, McKee was able to tighten the bolts on the BFV, eliminating the leak the same day as the excavation.

A second leak was located, marked above ground, excavated, and repaired the same way as the first. After repairing the two leaks found, the line passed pressure test.

While metallic force mains have been historically difficult to manage, a risk-based approach increases confidence in the condition of the pipeline.

After the Clean Water Act of the 70s required control of wastewater discharge, an increase in force main construction and management across the country was observed. As these assets are now approaching 50 years in age, reducing the risk of failure has become a major regulatory priority. Nothing grabs headline news like the failure of a force main, which can be extremely damaging to the environment and harmful to a utility’s reputation.

Historically, wastewater force mains have been difficult to manage, especially those made with ferrous materials, where the failure method is slow when compared to concrete pressure pipe.

As well, pressurized sewer mains have special operational challenges that don’t apply to gravity sewer mains as they typically cannot be taken out of service for inspection, and due to the presence of solids in the fluid, force mains represent a far more abrasive environment than potable systems such that assessment methods for water mains may not be applicable.

The presence of gas pockets increases the potential of corrosion in metallic pipes.

Gas pockets are of significant concern in force mains.

The primary failure mechanism of ferrous force mains is due to internal corrosion. Gas pockets are of significant concern in force mains, as concentrations of hydrogen sulfide gas within wastewater can be subsequently converted to sulfuric acid by bacteria in the slime layer on the pipe wall. This may cause corrosion and eventual breakdown of the pipe’s wall.

Therefore, a first step in assessing force main condition should be the identification of gas pocket locations within the pipeline.

Pure Technologies has performed an analysis of force mains inspected using acoustic based technologies in order to better characterize the frequency and location of gas pockets. Based on the analysis, it was found that 72% of gas pockets were not at known high points or air release valves, therefore, the most precise way to identify gas pockets within a force main is through the implementation of inline acoustic inspection technologies.

The collection of gas pocket locations alone will not indicate the condition of the pipeline, but instead identifies locations where an increase in corrosion potential is observed. To ascertain the true condition of a pressure pipe, higher resolution electromagnetic technologies are required. These technologies measure pipe wall thickness in ferrous materials and broken wire or bar wraps in concrete pressure pipe.

Once the condition data is collected, advanced analytics can be applied to estimate the pipeline’s remaining useful life.

“Previous analyses involved straight-line assumptions – comparing the pipe wall thickness at installation against what it is today. However this doesn’t give an accurate picture of how pipes degrade…by using statistical modeling we can develop a more predictable degradation rate based off of over 14,000 miles of inspection data Pure has collected over the past 30+ years.”

Jennifer Steffens, Market Sector Leader, Water and Wastewater, Pure Technologies

Desktop studies are not always reliable.

While often the first thought is to replace the aging wastewater assets based on factors such as age and failure history, this option makes neither logical nor financial sense. With so many miles of buried pipelines and such limited capital budgets, utilities don’t have hundreds of millions to spend on replacing pipelines which still have remaining useful life.

At Pure Technologies, we believe there is a better way. A more feasible approach to ensuring the safe operation of force mains is to undertake a risk-based approach to manage their operation. A risk-based approach will provide decision intelligence on which assets require rehabilitation or replacement to extend their useful life. Or which assets can be left alone.

Our approach is to help utilities evaluate the current state of their buried infrastructure and provide them with high confidence condition and operating data.   We then couple this with our years of extensive experience and project history (more than 12,000 kilometers of pressure pipe assessment) to provide utilities with actionable information, which allows them to make informed decisions as to the management of these critical assets.

The value of a risk-based approach to manage force mains.

Utilities that embrace a risk-based approach to manage their force main inventory have found that on average they can safely manage their force mains for roughly 5 to 15 percent of the replacement cost. This pragmatic approach focuses on providing real condition data through assessment, which can be used to selectively renew isolated areas of damaged pipe in lieu of capital replacement.

At Pure, we recommend a risk-based approach to manage wastewater force mains by focusing on four main areas:

  • Preliminary Risk Analysis
  • Internal Corrosion Potential Surveys using Inline Acoustics
  • Pipe Wall Assessment using Advanced Technologies
  • Condition Data Analysis and Advanced Risk Assessment

Some of the common reasons leading to failure on ferrous pipes.

Preliminary Risk Analysis

Preliminary analysis includes collecting the right data to develop a prioritized plan for assessment, including the selection of appropriate technologies. To help make preliminary decisions, Pure collects all available information to understand the history of the pipeline and the likely failure modes.

The data analysis will provide an understanding of the construction and context of the pipeline. Data of interest typically includes pipe characteristics, installation factors, environmental and performance-related data, operational data, and failure data.

Acoutic-based SmartBall® tool locates leaks and gas pockets

Acoustic-based SmartBall® tool locates leaks and gas pockets.

Sahara is an inline tethered tool used to locate leaks and gas pockets in pressurized lines.

Internal Corrosion Potential Survey.

An internal corrosion potential survey uses inline tools to locate gas pockets that can increase the potential for corrosion and eventual breakdown of the pipe wall. Pure Technologies typically deploys its acoustic-based SmartBall® leak and gas detection tool, as well as its tethered Sahara® leak and gas pocket detection platform to locate gas pockets in pressurized lines of all materials.

Pipe Wall Assessment.

While the presence of gas pockets may indicate areas of potential concern, it will not give a quantifiable answer as to the structural life of the pipe.

Pipe wall assessment is completed using a variety of technology solutions to identify defects and deterioration of the pipe wall in a variety of pipe materials. For pipe wall assessment of metallic force mains, common internal electromagnetic technologies include the PipeWalker® and PureRobotics® platforms, as well as the free-swimming 24-detector PipeDiver® assessment tool, developed to identify electromagnetic anomalies indicating pipe wall loss.

PipeDiver® assessment tool identifies electromagnetic anomalies indicating pipe wall loss.

Condition Assessment Analysis.

Condition data analysis and risk assessment evaluates how to safely renew or extend the life of force mains. The risk evaluation considers not only the probability of failure (condition) of the force main based on inspection data, but also the consequence of failure in order to make sound engineering decisions.

Understanding the risk of the pipeline is an important step in selecting and justifying the appropriate condition assessment methods. As the risk of the asset increases, the value of using high-resolution comprehensive assessment techniques increases. Higher resolution data results in more confident decision making, and would justify and prioritize the application of assessment techniques.

Diagnostic analytics helps utilities move risk assessment forward.

In the past, inspections were done, the data analysed, and the results passed on to the utility. Pure Technologies now offers a more holistic program of diagnostic analytics. This includes analysis of what caused the corrosion problem within the pipe wall, what the impact the corrosion has on the life of the pipeline, and a prescriptive analysis of how it needs to be repaired or rehabilitated.

The next step gathering momentum? Predictive analysis to elongate service life.

 

For this Vancouver Island community, tight deadlines, plug valves, and a rising tide were among the challenges faced during this condition assessment project.

Sometimes the catalyst for a pipeline inspection can come from an unexpected source. In this instance, the story began when it was noticed that a sewer pipe was exposed from erosion during low tide along the beach. That observation set the wheels in motion for an eventual inspection of a critical force main that services approximately 41,000 residents in both the Town of Comox and the City of Courtenay on the eastern coast of Vancouver Island.

The pipeline was installed in the early 1980s, and consists of an 8.75 km large-diameter force main that connects the City of Courtenay, Town of Comox and K’ómoks First Nation Community to the Comox Valley Water Pollution Control Centre (CVWPCC). This includes a five-kilometer portion buried in an “intertidal” foreshore section (area between high and low tide).

Over time, a section of beach eroded and exposed the line to coastal wave action (high tide hides the pipe). The Comox Valley Regional District (CVRD) took steps to restore the beach section where pipeline had been exposed, and began developing plans to relocate the exposed force main off the foreshore.

Island community concerned about pipeline risk of failure.

Sensitive location and potential environmental consequences strike nerve with community.

A new concept was developed that would utilize a portion of the existing force main within the foreshore but remove from service the exposed force main. Due to its sensitive location and the environmental consequences of a potential failure, the CVRD elected to complete a highly specialized pipe condition assessment on the entire length of the line to better understand the remaining service life and condition of the force main. As a result, the project timeline was tight, as CVRD needed imminent results to proceed with corrective action immediately should it be required.

The assessment challenges began from the get-go.

The inspected portion of the pipeline was built of two different pipe materials (PCCP and BWP) and three different pipe diameters (450-, 750- and 820-mm). As well, the critical line could not be taken out of service. The CVRD consultant, Associated Engineering, assisted in developing the request for proposal (RFP) process used to select Pure Technologies (Pure) to conduct the condition assessment, which included an electromagnetic inspection, structural curves, leak and gas pocket detection, and transient pressure monitoring.

Pure proposed the acoustic-based SmartBall® tool for the leak and gas pocket detection, and its free-swimming PipeDiver® inspection platform for the electromagnetic inspection of the line.

“This project had a lot of challenges, especially since the asset was so critical to the region. However Pure was able to help us understand the true condition of the line without requiring a shutdown of the critical force main, and has given us defensible information to make informed decisions in the future.”

Kris La Rose, Senior Manager Water/ Wastewater Services, Comox Valley Regional District

Pipeline alignment follows along the Vancouver Island coast.

Transient pressure monitoring used to understand surge pressures within the line.

First, transient pressure monitors were installed at the Courtney Pump Station (CPS). For more than 4 weeks, the recorded pressure data was used to understand the operational and surge pressures within the force main and their impact on the structural integrity of the pipeline.

SmartBall® technology detects and locates acoustic signature related to leaks and gas pockets.

While transient pressure data was collecting, Pure deployed its proprietary SmartBall technology, a multi-sensor tool used to detect and locate the acoustic signature related to leaks and gas pockets in pressurized pipelines.

The tool has the ability to inspect long distances in a single run, and while the SmartBall is deployed, the pipeline remains in service, limiting disruption to customers.

PipeDiver tool collects electromagnetic data regarding the pipe wall.

PipeDiver® electromagnetic technology designed to assess PCCP, BWP and metallic pipes.

In addition to utilizing the SmartBall tool, Pure chose to deploy the PipeDiver platform, a free-swimming condition assessment tool that collects electromagnetic data regarding the pipe wall, and operates while the pipeline remains in service, an important factor for the force main inspection. The tool travels with the product flow and utilizes flexible petals to navigate plug valves, tees and bends in the pipeline.

Crews had to retrieve the PipeDiver tool within a short 20-minute time window.

Tight time-frame for tool insertion and retrieval of sensor data.

Due to the criticality of the line, and a small capacity wet well at the CPS, the inspection teams had a very short time window (20 minutes) to insert the inspection tools. The small capacity wet well also meant that boosting flows was limited – if pumped too hard, the wet well would draw down and empty, and if pumped too slow, the PipeDiver tool could get lodged at the inline plug valves. (Low flow rate is not a significant problem for the SmartBall tool.) The solution was to first use the SmartBall inspection tool to test the flows in order to optimize the inspection approach for the PipeDiver run.

While the low flow rate slowed the SmartBall inspection, a forecast of rain moved up the PipeDiver run a day ahead in order to take advantage of extra flows that could be provided by the wet weather. The tool also had to navigate a series of 90-degree bends and a plug valve with a small port width in the pump station pipe.

Tracking the tools along the beach was fraught with potential for problems. Inspection crews needed to monitor the tidal forecasts in order to access the tracking sensors during the tide ebb, which meant a short window to retrieve the sensor data.

In spite of the challenges and risk, the dynamic four-day inspection proved successful, and went off without a hitch. The Pure Technologies crew and CVRD operators worked very well together, and their collaborative efforts ensured that this important project was successfully completed.

Damp weather didn’t dampen the inspection ingenuity of the team.

Data analysis indicated no electromagnetic distress on inspected pipes.

Based on the inspection data, Pure analysts identified zero (0) leaks, one (1) acoustic anomaly associated with trapped gas, five (5) acoustic anomalies characteristic of transient gas and two (2) acoustic anomalies associated with entrained gas. In particular, gas pockets are of significant concern in force mains, as concentrations of hydrogen sulfide gas within wastewater may be subsequently converted to sulfuric acid by bacteria in the slime layer on the pipe wall.  This may cause corrosion and eventual breakdown of the pipe’s exposed surface.

The results also showed no indication of electromagnetic distress on the inspected pipes, which was good news, in spite of the corrosive salt water environment.

Overall, the CVRD was pleased with the inspection results, as they were able to understand the condition of the pipeline and make an informed decision for capital improvements. The project demonstrates how the region uses actionable data to effectively manage their finances and risk, while continuing to provide the community with a safe and reliable delivery of wastewater.

 

Case Study

Artis REIT is an unincorporated closed-end real estate investment trust primarily focused on creating value for unitholders through the investment in and ownership of quality commercial properties in select markets. Artis REIT’s portfolio is comprised of industrial, retail, and office properties in Canada and the United States.

Project Details

Services
SoundPrint® Acoustic Monitoring – Parking Garages

Monitoring system commissioned in February 1994

System has been maintained and upgraded as needed, operating continuously since commissioning

Structure Type
Two-way unbonded post-tensioned concrete ground level slab above parking garage
Monitored Area
5,967 m2
Number of Zones
3
Number of Sensors
60

Project Highlights

System has performed in excess of 97% of efficiency over its lifespan

Detected and located 181 wire failures to date, of which 81 have been confirmed by physical inspections

Annual post-tensioning investigations planned according to monitoring results with as needed tendon replacements

Predictable wire failure rate on 8.1/year has allowed for accuracte forecasting of tendon replacements, averaging 6.6/year since 1999

Identified critical area to allow for focused remediation efforts

Challenge
Prior to the installation of the monitoring system, a single post-tensioning strand erupted from the slab surface. Investigations of the state of the ground level slab revealed significant waterproofing issues on the slab edges and water ingress into the tendons. Selective, invasive, inspections on strands throughout the structure were undertaken and resulted in 164 strands replaced from a total of 850. The status of the remaining tendons was uncertain, and a comprehensive monitoring solution was desired to identify areas of active corrosion.

Solution
In order to gain further insight into the deterioration rates of the structure, a SoundPrint monitoring system was installed in February 1994. The system was the first of its kind, and the monitoring experience gained was used to refine monitoring protocols and equipment. Improvements in the technology led to significant upgrades in 2001 and 2008, without any significant interruption to the data acquisition. Overall, the system has been in continuous operation in excess of 22 years and operated at over 97% efficiency through its life.

Results
Physical investigation of detected events have been regularly undertaken by qualified consulting engineers.  The process has resulted in the following:

  1. Wire events identified and located by Pure Technologies, and reported to client and consulting engineer.
  2. Consulting engineer schedules annual investigation of existing recesses and/or creates new recesses to check condition of the strands on which the wire events may have occurred.
  3. Based upon the condition of the strands inspection, the consultant recommends tendons for replacement.

Through these inspections, 81 wire failures have been confirmed by the finding of tension deficient cables in the reported areas. The monitoring results are displayed in the chart, which shows the linear nature of the post-tensioning deterioration in the three (3) ground level slabs. This consistent rate allows the client to accurately budget tendon replacements to maintain the structural integrity while minimalizing unexpected costs and interruptions to the garage operation.

In North America, the material and size of pipes that make up water and sewer networks range widely. Because these pipeline systems are so complex, it requires a strategic approach based on risk and real data for effective long-term management.

Worker inspecting pipe

Historically, however, it has been challenging to gather real data that can shape defensive capital decisions for an entire system. The assessment of metallic pipelines — which make up most water and pressurized sewer networks — differs from prestressed concrete cylinder pipes (PCCP), both in terms of failure modes and in the fact that metallic pipe materials are featured in both transmission and distribution networks.

While PCCP assessment and management have been successfully used by utilities for years, effective assessment solutions for ferrous pipe have only recently been commercialized.

In 2011, Pure Technologies began an initiative to help close the gap in metallic pipe assessment technologies, and focus attention on gathering honest feedback from proactive utilities on what solutions are needed to effectively manage metallic pipe.

Seven years later, Pure Technologies reports that notable progress has been made with the development and advancement of assessment technologies for metallic pipeline networks.

Team of workers with a metallic pipe

Many proactive utilities involved in guiding Pure’s research efforts

Proactive utilities have been involved in the metallic pipe initiative, and instrumental in the development of new inspection tools for metallic pipe, both by providing feedback that helps guide research and development, and by providing opportunities that allow solution testing in live operating conditions. As a result of these efforts, there has been significant improvements to the technologies available to utilities for assessing the condition of metallic pipelines in both transmission and distribution networks.

For large-diameter transmission mains, there is a well-developed business case for assessing these mains as they approach the end of their useful life. These pipelines typically carry a high replacement cost and are higher risk — due primarily to their size and criticality — making it important for utilities to fully understand the condition of the asset.

Armed with real condition data, utilities can make a defensible renewal or replacement decision about the pipeline. Based on well over 14,000 miles of data, Pure Technologies has found that only a small percentage of pipes are in need of immediate renewal.

Small diameter metallic pipe leak

Case for using inline tools for small diameter pipelines

In distribution networks, however, the case for condition assessment is more challenging as smaller pipelines can sometimes be replaced cost-effectively. Despite this, the process for making a replacement decision should be based, whenever possible, on risk and real data.

With the EPA suggesting that between 70 and 90 percent of pipes being replaced have remaining useful life, the case is even stronger for collecting condition data to drive the decision making to help utilities spend their replacement dollars more efficiently and avoid replacing pipe with remaining useful life.

In some instances with smaller diameter pipes, it is often cost-efficient to use inline tools to gather detailed screening data on a pipe-by-pipe basis to determine if replacement is necessary.

A new approach to metallic pipeline management

While there is no silver bullet technology for assessing metallic pipelines, Pure has developed a flexible, risk-based approach to help utilities better understand their infrastructure, gather actionable data and prioritize both short and long-term management efforts.

Over the past few years, Pure has worked along proactive utilities to develop its data-driven Assess and Address® approach, which focuses on four main areas:

  • Understand
  • Assess
  • Address
  • Manage

Through the implementation of programs across North America, Pure has found that the majority of pipelines 16 inches and above can be cost-effectively managed for between 5 and 15 percent of the replacement cost.

Starting an effective pipeline management program

The first step of any pipeline management program is understanding the system-wide risk along with the benefits and limitations of assessment solutions. This allows for the development of a defensible management strategy that can be implemented to maintain and extend the life of the assets.

Many technologies now exist to provide a snapshot of a pipeline condition at various levels of confidence. It is therefore prudent for utilities to approach technology selection and subsequent analysis based on the risk of each pipeline.

A more thorough risk assessment involves estimating the Consequence of Failure (CoF) and the Likelihood of Failure (Lof) of each pipeline based on internal knowledge, operational history and pipeline characteristics. This initial risk assessment determines which areas of the system require further assessment to acquire real condition data and provides the utility with the necessary information to make an informed technology selection.

By using risk to guide management strategies, owners can ensure they are implementing the right approach, at the right time, with the lowest financial impact. The goal of a management program should always be o focus resources on managing the asset while safely getting the most service life out of the pipeline.

Sinkhole in a street

Reducing the Consequence of Failure

Reducing CoF comes down to improving emergency events through field operations efficiency. Studies have shown that the time to shut down a pipeline had more impact on the consequence of failure than the diameter of the pipeline.

Utilities can reduce CoF — and in turn risk — by gaining a better control on their system, which can be achieved two ways:

  • 1. Adding valves and redundancy in the system
  • 2. Knowing the location, condition and operability of control points

For example, if a pipe fails and utility operations staff are unable to locate valves — or the valves are inoperable when they are located — it will take longer to isolate a pipe failure. This will result in greater damage, more water loss and longer outages and repair times as a result of the failure. Implementing a proactive program for control assets that focus on providing better data for field staff reduces CoF by decreasing emergency response time.

Reducing the Likelihood of Failure through condition assessment

Many factors influence the likelihood that a pipeline will fail. Metallic pipelines, specifically, have a variety of failure modes and require a wide array of technologies to accurately assess their condition. Until recently, technologies for metallic pipe assessment have been unavailable or limited in their viability.

As a result, lower risk metallic mains have historically been prioritized for replacement using age, material and break history, while higher risk mains have sometimes been assessed with test pits along the length of the pipeline. After test pitting, statistical methods are used to extrapolate the condition of the test pit locations along the entire pipe length.

Through the development of metallic assessment solutions, condition data shows that pipe distress is often random and localized, meaning that an area of distress identified during the test pit method may inaccurately identify the entire pipeline as distressed, conversely, identify the entire length of pipeline as in good condition.

The development of reliable inline condition assessment tools provides owners with pipe-by-pipe data that gives a more complete picture of the actual condition of the pipeline. This allows for a more targeted management of small sections of pipe instead of generalizing the condition of an entire pipe length. It also allows for the collection of real data to drive pipeline renewal, which allows for more defensible capital decision making.

Case Study

This preeminent steel producer is a North American leader in advanced steel manufacturing technology. Typical to most steel processing plants, this mill uses recirculated water for a broad variety of purposes, including cooling the blast furnaces, quenching slag, and drawing heat from the overall hot plant environment.

Project Details

Services
PureRobotics® electromagnetic condition assessment
PureRobotics® HD-CCTV inspection
Risk assessment and prioritization
Single day mobilization and inspection
Timing
2015
Pipe Material
Lined Cylinder and Embedded Cylinder Pipe (Types of PCCP)
Inspection Length
0.68 miles
Diameter
48-inch & 54-inch
Transmission Type
Recirculating Water

Project Highlights

0.68 miles (1.09kms) total distance inspected

117 pipes inspected

31 pipes with broken wire wraps

25 repaired and replaced pipes

Challenge

The lines used for recirculating water play a critical role in the operation of a steel plant. When the mill scheduled a brief operational shutdown, they wanted to quickly understand the true condition on a section of their return and supply lines in order assess and prioritize risk and rehabilitate any problem pipes.

On June 2015, the steel mill engaged Pure Technologies Ltd. (Pure) to conduct a non-destructive evaluation of the prestressed concrete cylinder pipe (PCCP) sections in the 48 inch Recirculating Water Return (RWR) and the 54-inch Recirculating Water Supply (RWS) Lines.

The inspected portion of RWR Line is composed of single wrap lined cylinder pipe (LCP). The inspected portion of RWS Line is composed mainly of single wrap embedded cylinder pipe (ECP) without shorting and a short section of single wrap LCP. The pipes were manufactured in 1981.

Pure Technologies previously inspected the 48-inch RWR Line in July 2009 and January 2010 and the 54- inch RWS Line in January 2010. To facilitate a direct comparison between past and current inspection results, the data from the 2010 inspection was reviewed to ensure data analysis continuity.

Solution

The purpose of the single day inspection was to locate and identify pipes that have broken prestressing wire wraps, using Pure’s electromagnetic inspection technology. An electromagnetic inspection provides a non-destructive method of evaluating the baseline condition of the prestressing wire, the structural component that provides the pipe’s strength.

Since the line was dewatered, the survey requirements would also include a visual inspection, which led Pure to recommend the tethered PureRobotics platform, as it is equipped with a high definition CCTV camera to deliver a live video stream from inside the pipe.

The robotic transporter is designed to carry a variety of sensors and tools and can travel a total of 2.9 kilometers from a single point of access. With the new generation of robot, the speed is doubled to 85 feet per minute, which greatly improves efficiency in the field, a huge benefit during time-critical shutdowns.

The inspection went off without a hitch, as crews from the plant had earlier prepped all access points. Pure simply set up a tripod with a chain fall, and lowered the tethered robot through a manhole into the pipe to begin the inspection journey.

Results

Overall, the survey was a low effort, little disruption inspection, conducted in less than a day.

The inspection covered a cumulative distance of 0.68 miles and spanned a total of 177 pipes.

Of these pipes, 25 are replacement pipes or have been previously repaired using carbon fibre.

Analysis of the data obtained during the inspection determined that out of the remaining 152 pipes, 8 pipes in the 48- inch RWR Line and 23 pipes in the 54-inch RWS Line displayed electromagnetic anomalies consistent with prestressing wire damage, ranging from 5 to 40 broken wire wraps.

With the actionable information delivered by Pure, the mill was able to learn about the current condition of their critical assets, and strategize rehabilitation and repair initiatives that meet the goals of their production. In the end, effective asset management using the latest tools and strategies helps reduce costs through targeted spending.

Case Study

The City of Calgary provides water and wastewater services for more than 1 million people in the Greater Calgary area. For many municipalities, accurate and regular condition assessment of large-diameter pressure pipelines has become more important in recent years as these assets continue to age and risk of failure increases.

In Calgary, three critical feedermains (14th Street/North Hillhurst, John Laurie and Top Hill) are each constructed of different materials: lined cylinder pipe (LCP), prestressed concrete cylinder pipe (PCCP) and bar wrapped pipe (BWP). The pipes range from 750mm (30-inch) to 900mm (35- inch) in diameter.

Project Details

Services
PureRobotics® electromagnetic condition assessment

PureRobotics® HD-CCTV inspection

Risk Prioritization

Timing
2015
Pipe Material
PCCP, LCP, BWP
Inspection Length
4.74 km (2.9 miles)
Diameter
750mm-900mm (29-35 inch)
Transmission Type
Water

Project Highlights

Condition assessment on 2.92 miles (4.7 kms) of feedermain pipes

Data identified 8 pipes with electromagnetic anomalies consistent with broken pressing wire wraps

HD-CTTV identified 3 pipes with damaged internal mortar and exposed cylinder

Challenge
In an annual condition assessment program, The City inspects its PCCP, BWP and LCP for deterioration. By identifying isolated pipe sections with deterioration, the City is able to make selective repairs in favor of full-scale replacement, which comes at a high cost and may replace sections with significant remaining useful life.

In data collected from more than 14,000 miles of pressure pipe condition assessment, Pure Technologies has found that only a small percentage of pipes (less than 5 percent) are in need of repair and therefore have years of service left. Condition assessment data also suggests that pipe distress is localized, and significant ROI can be achieved by locating and addressing isolated problems through structural inspection.

Solution
To inspect the three feedermains, the City deployed PureRobotics®, a tethered robotic system that delivers live video, and is equipped with electromagnetic technology that can be configured to inspect a variety of pipelines and materials with different operational conditions.

In BWP, the technology identifies and locates broken bars and areas of corrosion on the steel cylinder, which are the main indication this type of pipe will eventually fail. Although BWP looks similar to PCCP in cross section, the design and materials are significantly different.

PCCP is a concrete pipe that remains under compression because of the prestressing wires, with the thin-gauge steel cylinder acting as a water membrane. With BWP, the cylinder plays a much larger role in the structural integrity of the pipe. BWP is essentially designed as a steel pipe with mild steel used to manufacture the steel cylinder and steel bars. PCCP utilizes mild steel for the cylinder, but high strength steel is utilized for the wire, which is wrapped under high tension. As a result, the bar in BWP and wire in PCCP respond differently to environmental conditions that facilitate corrosion.

The high strength steel wire in PCCP is smaller in diameter and wrapped under higher tension, therefore corrosion makes it quite vulnerable to breakage. The mild steel bars in BWP are thicker in diameter and wrapped under less tension, therefore corrosion takes significantly longer to lead to breakage. The type of failure is also much different; PCCP tends to fail suddenly with a large dispersion of energy. This type of failure is less likely in BWP where failures are similar to steel pipe with long periods of leakage occurring prior to rupture. Because of the differences in make-up, BWP and PCCP are inspected using unique methods to determine their structural condition.

Results
Of the 694 pipes cumulatively inspected over the 4.74 kilometers, eight (8) pipes were identified with electromagnetic anomalies consistent with broken prestressing wraps. Additionally, two (2) pipes were found with an anomalous signal not characteristic of broken bar wraps that can be attributed to a change in the pipe cylinder.

Evaluation of the John Laurie Boulevard Feedermain concluded that one (1) pipe was identified to have an anomalous signal likely caused by a non-uniform cylinder. Images obtained from the robot indicated this pipe has damaged internal mortar and exposed cylinder. Additionally, two (2) pipes on this feedermain were identified to have damaged internal mortar and exposed cylinder, but did not contain anomalous signals.

The City of Calgary was pleased with the results, and through condition assessment, has been able to identify and address individual distressed pipe sections on otherwise serviceable feedermains. This has allowed the City to avoid potential ruptures, while increasing service reliability and useful life of the feedermains.

Case Study

The City of Montreal supplies drinking water and wastewater services to a population of nearly 1.9 million people. Starting in 2007, Pure Technologies (Pure) began working with the City’s potable water transmission division on a pipeline assessment program that included electromagnetic (PureEM) inspection and acoustic monitoring.

In 2015, as part of a pre-emptive program to reduce loss of non-revenue water and understand the condition of their pipes, the City partnered with Pure to conduct an ongoing, three-year leak detection survey on a series of critical pipes within its potable water network located mostly in the downtown core.

Project Details

Services
Sahara® leak detection

CCTV visual inspection

Timing
2015-Ongoing
Pipe Material
BWP, Steel, Cast Iron, PCCP
Inspection Length
28.9 km (18.5 m)
Diameter
500mm – 1200mm (20-inch – 48-inch)
Transmission Type
Water

Project Highlights

20.8 miles (33.5 kms) inspected to date

46 insertions completed

24 leaks identified

9 leaks identified as feature leaks

Challenge
The City recognized the value of detecting leaks, however small, to prevent these from developing into greater problems. While leaks occur most frequently on small-diameter distributions mains, leaks and ruptures on trunk mains are a much bigger concern for utility operators due to the relatively higher consequence of failure.

In addition to physical losses of water caused by a series of small leaks, the escaping water can eventually erode the surrounding soil making the area more prone to washouts or sinkholes, a major headache especially in densely populated areas. Leaking water can eventually find its way to the surface, or into sewers, overburdening the system. Unplanned excavations to repair unforeseen leaks can also erode consumer confidence in a public utility.

Solution
For its multi-year leak detection program, the City requested Pure to deploy its highly reliable and precise Sahara® acoustic video inspection on 46 kilometers of pipelines chiefly in the downtown core. The pipeline sections consist of PCCP, BWP, cast iron and steel.

The Sahara platform comes with a variety of sensor tools to perform the inspection. This includes an acoustic sensor to perform leak and gas pocket detection, and high-resolution video camera to assess internal pipe conditions.

Because the Sahara tool is drawn by product flow via a small drag chute, and is tethered to a data acquisition unit on the surface, it gives the operator close control to confirm suspected leaks, gas pockets and other visual anomalies. The tool can visually confirm pipe irregularities, continuously recording, allowing for both real-time and post-processing analysis.

For the Montreal project, the purpose of the Sahara inspection was to assess the condition of the pipeline by identifying and locating leaks, pockets of trapped gas and to identify larger visual anomalies utilizing Closed Circuit Television (CCTV) footage collected during the inspection. The data would help shape the rehabilitation urgency and timing.

 

Results
To date, Sahara has had 46 insertions and a total of 33.5 kilometers (20.8 m) have been assessed. Analysis of the data identified 24 leaks and zero (0) gas pockets in the pipeline sections inspected. The Sahara sensor was tracked above ground using the Sahara Locator® device to track the Sahara tool and locate any potential leaks or anomalies found.

 The assessment is proving its worth from a verification viewpoint, and the leaks have been either repaired or addressed for prioritization. The current program is scheduled for completion by 2017.

With its pre-emptive leak detection program, the City is Montreal is a great example of a smart water manager taking proactive efforts at keeping its network in healthy shape.

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Case Study

In 2015, Utilities Kingston retained the services of Pure Technologies to perform a condition assessment on the Dalton Avenue (North End) Pump Station Force Mains.

At approximately 35 years, each asset was entering a critical stage of its life-cycle. The purpose of the assessment was to identify the structural condition of the 450mm and 600mm force mains, both of which are approximately 1,550 meters long and follow a parallel route.

The assessment included transient pressure monitoring, a SmartBall® leak and gas pocket detection survey, and a PipeDiver® electromagnetic inspection of the pipeline.

Project Details

Services
SmartBall® leak and gas pocket detection
PipeDiver® electromagnetic inspection
Transient pressure monitoring
Risk of failure evaluation
Timing
2015
Pipe Material
Ductile Iron, Steel, Reinforced Concrete
Inspection Length
3.05 kilometers (1.9 miles)
Diameter
450mm to 600mm (18 inch to 24 inch)
Transmission Type
Wastewater

Project Highlights

 

3.05 kms cumulative distance of survey

 

1 acoustic anomaly associated with transient gas (SmartBall inspection)

55 pipes with EM anomalies characteristic of localized wall loss (PipeDiver inspection)

 

Zero leaks detected

 

Challenge

The older of the two force mains is 450mm (18-inch) in diameter, constructed of ductile iron built in the late 1950s, and had failed several times over its lifetime. The newer of the two force mains is 600mm (24-inch) in diameter, built from reinforced concrete (RCP) and steel, with two sections of suspected metallic pipe, which was not confirmed in the profile drawings.

As the pipe material specifics were still unknown at the time of the inspection, Pure Technologies elected to conduct a PipeDiver run to accommodate both possible types of pipe material – assumed by all to be bar wrapped pipe (BWP) and prestressed concrete cylinder pipe (PCCP).

Historically, it has proven challenging to assess the condition of pressurized mains that carry sewage, especially those made with ferrous material. Metallic force mains have special operational challenges that don’t apply to gravity sewer systems, and due to the presence of solids in the flow, force mains represent a far more abrasive environment than potable water systems.

Gas pockets are of significant concern in force mains, as concentrations of hydrogen sulfide gas within wastewater may be subsequently converted to sulfuric acid by bacteria in the slime layer on the pipe wall. This may cause corrosion and eventual breakdown of the pipe’s exposed surface.

Solution

Transient pressure monitors were installed on the header of each force main and for nearly five weeks the recorded pressure data was used to understand the operational and surge pressures within the force mains and their impact on the structural integrity of the pipelines.

Utilities Kingston began the initial force main condition assessment by deploying SmartBall technology, a free-flowing multi-sensor tool used to detect and locate the acoustic sounds related to leaks and gas pockets in pressurized pipelines. The tool has the ability to inspect long distances in one run, and requires only two access points, one for insertion and one for extraction. SmartBall is an effective condition assessment tool for force mains, which don’t typically feature butterfly valves, allowing the SmartBall to roll through the line quite easily, collecting acoustical data.

Following the SmartBall run, UK deployed the free-swimming PipeDiver assessment tool, which travels with the product flow, and utilizes flexible petals to navigate butterfly valves, tees and bends in the pipeline. Originally designed for use in pressurized concrete cylinder pipes (PCCP), the tool has specialized electromagnetic sensors (PureEM) to identify and locate broken prestressing wire wraps, (one of the main structural components and failure modes of a prestressed concrete pipe).

Historically, technologies available to assess the condition of metallic pipe have been limited. This led Pure TEchnologies to develop the specialized PipeDiver for metallic pipes, equipped with advanced electromagnetic technology to identify broken bars in bar wrapped pipe, and localized areas of wall loss in BWP, steel and ductile iron.

Results

In the end, one (1) acoustic anomaly characteristic of transient gas on the 450mm force main was identified with data collected during the SmartBall inspection. No acoustic anomalies were identified within the 600mm force main during the SmartBall inspection.

Of the 650 pipes inspected with the PipeDiver tool, a total of 55 pipes in the 450mm Dalton Avenue Pump Station force main had electromagnetic anomalies characteristic of localized wall loss. These results represent a high percentage of distress along the length of the pipeline and indicate a high risk of failure.

Recommendations included an extended period of transient pressure monitoring as the maximum pressures recorded exceed the 600mm RCP design limitations. Utilities Kingston should also review the pressure reducing valves at the pump station and investigate the operating procedures to determine the cause of the transient pressures.

The fact-finding data collected from both the inspections and transient pressure monitoring gave Utilities Kingston a better understanding of their real, not assumed assets. The results, which included a DIP risk of failure analysis, were used to complete a structural evaluation of the force mains, and have provided Utilities Kingston with actionable information regarding any necessary repairs or rehabilitation.

Since 2007, utilities all over the world have been using the SmartBall® pipeline inspection platform to save millions of dollars in water loss and to fix leaks before they turn into larger problems.


Developed by Pure Technologies (Pure), the tool is trusted by utilities for two main reasons. One is for condition assessment purposes, and the other is for reducing non-revenue water. From a condition assessment perspective, SmartBall® is a proactive tool that can be used as part of a larger holistic approach to help identify problem areas that require repairs before they turn into bigger issues, and also to help utilities prioritize capital spending.

SmartBall inside a pipe.

Detect and locate acoustic sounds related to leaks and gas pockets

The primary purpose of the SmartBall tool is to detect and locate the acoustic sounds related to leaks and gas pockets.

“Unlike traditional correlators, the SmartBall sensors travel inline along the pipe, inspecting every inch of the water main to detect potential problems such as leaks and gas pockets. Based on thousands of miles of experience, the SmartBall tool has found three to four times more leaks than trunk main correlators, which are traditionally used in smaller diameter pipes, and are less effective for transmission mains and larger diameter pipes.”

Cam White

Business Line Manager, SmartBall

Deployed for long runs in one inspection for water and wastewater pipelines

What makes the SmartBall tool so remarkable is its ability to get into and out of pipelines very easily, and to be deployed for long runs in one inspection for both water and wastewater pipelines. The tool requires only two access points – one for insertion and one for extraction.

For insertion, the foam-shelled SmartBall tool is placed into a claw, compressed, and then lowered into the line through a 4-inch (100mm) or larger tap, all while the line is pressurized. Throughout the survey, Pure’s inspection team constantly monitors the SmartBall’s position as it traverses the pipeline collecting data.

  • An acoustic sensor listens for leaks and gas pockets.
  • An accelerometer and gyroscope measure the SmartBall’s movement, which can later be used for pipeline mapping.
  • A magnetometer measures the magnetic field coming off the pipe wall, data that can be used to find joints and other pipeline features.
SmartBall extraction process

Multiple insertion and extraction options available

There are many alternative options available to get the SmartBall in and out of a pipeline. Having multiple options reduces the money and effort required by utilities to support the inspection.

Once the inspection is complete, the data is extracted from the ball and sent to Pure’s data analysts where they will identify leaks and gas pockets.

As utility owners know, it can be expensive to excavate, and what SmartBall tool does is provide information that’s accurate, so clients can dig up the pipeline and find the leak the first time.

Rideau Canal, Ottawa

For the City of Ottawa, the SmartBall tool is used to locate “leak-where-predicted”

The “leak-where-predicted” scenario recently happened with the City of Ottawa when Pure deployed its SmartBall inspection platform to locate leaks and pockets of trapped gas along a critical transmission main, as part of a long-term condition assessment program for the municipality.

The Baseline Road Water Transmission Main is a high priority 1220mm (48-inch) diameter pipeline comprised of lined cylinder pipe (LCP).

For the City of Ottawa project, five (5) surface-mounted acoustic sensors were placed along the pipeline to track the SmartBall tool during the inspection. The SmartBall device was inserted into the pipeline through a 100mm drain near a hospital. Acoustic and sensor data was collected and recorded as the SmartBall tool traversed the pipeline for more than three kilometers.

From the survey results, Pure detected one (1) acoustic anomaly characteristic of a leak and zero (0) anomalies consistent with pockets of trapped gas.

The “leak-where-predicted” scenario recently happened with the City of Ottawa when Pure deployed its SmartBall inspection platform to locate leaks and pockets of trapped gas along a critical transmission main, as part of a long-term condition assessment program for the municipality.

The Baseline Road Water Transmission Main is a high priority 1220mm (48-inch) diameter pipeline comprised of lined cylinder pipe (LCP).

For the City of Ottawa project, five (5) surface-mounted acoustic sensors were placed along the pipeline to track the SmartBall tool during the inspection. The SmartBall device was inserted into the pipeline through a 100mm drain near a hospital. Acoustic and sensor data was collected and recorded as the SmartBall tool traversed the pipeline for more than three kilometers.

From the survey results, Pure detected one (1) acoustic anomaly characteristic of a leak and zero (0) anomalies consistent with pockets of trapped gas.

SmartBall inside a pipe and working zone map

Ground microphones fail, SmartBall tool succeeds

Although Pure was confident in the SmartBall leak detection data, sometimes it’s worth a try to verify an anomaly with a complimentary technology. In this instance, ground microphones, regarded as a conventional a leak detection tool, were deployed to try and detect leak sounds. Although the suspect area was marked, neither Pure nor the client could pick up leak-related sounds from the ground microphone.

Even though the leak was not picked up by the ground microphone, Pure was confident that the acoustic signature from the SmartBall was caused by a leak, based on more than 15 years of experience identifying leaks. That confidence and experience proved right, and when the suspected area was excavated, the leak was located within a meter of where the data analyst calculated the leak to be.

The results gave the City of Ottawa actionable data regarding the condition of their pipeline, and the City was able to fix the leak reducing non-revenue water loss and any potentially costly damage caused by the leak. It’s a great example of a proactive utility taking efforts to improve the reliability of its services.

Gateway of The North City of North Bay

On one hand, it may seem like a waste of capital dollars if you perform a pipeline condition assessment and the final analysis turns up no leaks. Alternatively, you can also look at the no-leak report as a good news validation story, especially when using the information to help establish an asset management plan.

Such was the case for a city of 51,000 situated between the shores of lovely Lake Nipissing and Trout Lake in Northern Ontario.

In September 2016, the  City of North Bay (City) retained the services of Pure Technologies (Pure) to perform a two-phase condition assessment on the Marshall Avenue Force Main (MAFM). The MAFM is a critical 508mm (20-inch) asbestos cement pipeline that services approximately half the city, and transfers wastewater from the Marshal Avenue Pump Station to the North Bay Sewage Treatment Plant.

Aerial picture with sewer map

The City was interested in exploring technologies to help them better understand the actual condition of their force main in order to implement a comprehensive asset management program using the inspection data.

To assist in the assessment, Pure Technologies elected to first conduct transient pressure monitoring, followed by a SmartBall® inspection to acoustically identify and locate leaks and pockets of trapped gas along the pipeline.

Transient pressure monitoring helps understand structural integrity of the pipeline

First, transient pressure monitors were installed at the pump station discharge header. For approximately six weeks, the recorded pressure data was used to understand the operational and surge pressures within the force main and their impact on the structural integrity of the pipeline.

When pipe wall degradation is combined with surge pressures, the likelihood of pipe failure can be significantly increased.  Evaluation of the pump station operation, such as pump start-up mode, typical and peak flows, operating and surge pressures, and surge protection, can provide important information on the stress.

SmartBall with its controls and tools

SmartBall tool provides acoustic signature related leaks and gas pockets

While transient pressure data was collecting, Pure deployed its proprietary SmartBall technology, a multi-sensor tool used to detect and locate the acoustic signature related to leaks and gas pockets in pressurized pipelines. The tool has the ability to inspect long distances in a single run, and while the SmartBall is deployed, the pipeline remains in service, limiting disruption to customers.

Unlike traditional listening tools like correlators, which have limited success on large diameter pipes, the free-flowing SmartBall technology provides a high degree of accuracy, since as the ball rolls inside the pipe, it can inspect every inch of the main to detect leaks and gas pockets.

From insertion to extraction, the SmartBall inspection took a little over four hours, with no unexpected events as anticipated during the planning stage.

SmartBall functionality chart

Results lead to effective management of finances and risk

Based on the inspection data, Pure analysts reported zero (0) anomalies characteristic of leaks, and 13 acoustic anomalies characteristic of pockets of trapped gas, mostly around air valves.  In particular, gas pockets are of significant concern in force mains, as concentrations of hydrogen sulfide gas within wastewater may be subsequently converted to sulfuric acid by bacteria in the slime layer on the pipe wall. This may cause corrosion and eventual breakdown of the pipe’s exposed surface.

Gas pockets combined with pressure transients can have significant impact on the pipeline, as vacuum conditions may be created. This can cause cavitation at the gas pocket as the transient gas passes, increasing stress on the pipe wall and therefore increasing the risk of failure if the structural capacity has been compromised.

City considering adding more air valves to help expel collecting gas

Based on a hydraulic evaluation of the pipeline, structural fatigue was not a concern, although test pits were recommended to determine asbestos cement thickness and gas pocket mitigation using swabs also recommended. In the near term, the City is considering adding more air valves to the pipeline to help expel collecting gas.

Overall, the City of North Bay was pleased with the project results, as they were able to understand the overall condition of the pipeline and make an informed decision for capital improvements of the Marshall Avenue Force Main. The project demonstrates how the City uses actionable data to effectively manage their finances and risk, while continuing to provide the community with a safe and reliable delivery of wastewater.

Massive pressured water leak

According to AWWA’s 2016 Benchmarking Survey, the average water and wastewater utility has seven breaks per 100 miles of piping every year. Tip-top systems experience just four breaks in that distance, while those at the bottom have 18.

While it’s interesting to note the difference in break rates, it’s unfair to compare one utility to another, as a multitude of factors come into play as to why pipelines can deteriorate to state of failure. Countless sources of stress both inside and outside a pipe related to geographical location, soil-pipe type interactions, age, and construction are among factors that can take their toll on the pipe’s condition.

Worker inspecting pipe

For utilities, the one constant across the spectrum is the acknowledgment that simply replacing pipeline assets is cost prohibitive, and that advanced condition assessment services like those provided by Pure Technologies (Pure) can help utilities confidently make informed decisions that significantly reduce capital and operating costs.

Single-episode blowouts garner all the attention

While single-episode blowouts are quite rare, these tend to garner most media attention, and cause the most obvious blowbacks to the pipeline operator. What the public doesn’t usually notice are the pinhole leaks, hairline cracks, corrosion and leaking gaskets that tend to occur first.

Most catastrophic failures are caused by a sudden unexpected stress such as a water hammer acting on an existing weak point in the pipe. There is a widely held belief that the failure process is a simple one, where a pipe corrodes to the point at which it can no longer withstand the applied internal and external forces, resulting in a main break. However, research has shown that the failure process is more complex than expected.

Corrosion plays a significant role in water main failures, but soil-pipe interactions, manufacturing techniques and human error are also important factors. Failures also take place in multiple stages rather than in a single episode. Early damage not only weakens portions of the pipe, it also allows water to escape, causing corrosion and washing out of the supporting soil.

Broken water pipe on a street

Age alone does not indicate high-risk pipes

Pipes at highest risk are typically constructed using dated materials or methods, running through an area with heavy vehicle traffic. Urban centers typically represent significant loss potential from damage caused by water main breaks as a result of high-density buildings, underground infrastructure, important traffic thoroughfares, and economic loss potential of power, gas, water utilities and legal cases.

The net result is that age alone cannot be relied on as an indicator of a high-risk pipe.

Broken pipe

Types of pipe material and typical cause of failure

Prestressed concrete cylinder pipe (PCCP) has a unique failure mechanism: high strength steel pre-stressing wires that provide strength to the pipe can become distressed and reduce the structural integrity of the pipe. Broken wires can be caused by physical damage to the pipe, corrosion, or hydrogen embrittlement.

Areas of broken wires may be accompanied by leaks, especially in pipelines smaller than 48 inches in diameter, where the internal steel cylinder corrodes at the same rate as the wires or where water escaping through the joint encourages corrosion. Leakage has been proven to be a key indicator of structural condition in lined cylinder pipe, a type of PCCP in which the prestressing wires are placed directly on the steel cylinder. These types of leaks can create voids around the pipe and introduce added stress at an existing weak point.

Cast iron pipes corrode, become brittle and are prone to cracking. Many older North American cities have cast iron pipes that were installed in the 1800s, prior to the existence of pipeline standards, when methods of construction were non-uniform and advanced quality control programs did not exist. Consequently, many pipelines were installed using what are considered poor construction practices by today’s standards.

Ductile iron pipes have failure mechanisms similar to those of cast iron pipes; however they become less brittle and consequently degrade at a slower rate. These pipes may be capable of supporting large leaks for longer periods of time without failing immediately.

Plastic and polyvinyl chloride (PVC) pipes are less prone to corrosion and less brittle than iron pipes. Failures in these pipes are often traced to leaking joints where the escaping water creates voids around the pipeline, causing unplanned stresses on the pipe.

Steel pipes primarily fail due to loss of integrity at welds, and external corrosion causing severe pitting and weakening the pipe wall. Both losses of joint integrity and through-wall corrosion pits lead to leakage long before failure. Older steel pipes in aggressive environments are capable of sustaining massive levels of leakage for decades before failing.

Workers digging with mechanical shovel

Making ongoing condition assessment part of proactive asset management

While pipe material and typical pipe stresses are factors that can contribute to a state of pipe failure, it remains impossible to compare one pipeline to another, and to make generalized statements about remaining service life, especially based on age and depreciation. Instead, it pays to conduct ongoing condition assessment, and then to use that risk-driven asset data collection to reduce the likelihood of replacing pipe that can safely and effectively serve communities for several more years.

Staff members behind an open pipe

When you’re a regional water authority with a sound way to identify problems with your aging water pipeline before the problems get bigger, it’s cause for a celebration, highlighted with speeches, live demonstrations and cake included in the ceremony.

In late November 2016, a delegation of government officials, special guests and educators gathered in London, Ontario Canada  to celebrate the successful funding, installation and commissioning of a 60 km (37 miles) Acoustic Fiber Optic (AFO) system installed on the Lake Huron Water System’s water transmission pipeline.

Map with pipeline location

Pipeline draws water from near Grand Bend to terminal reservoir north of London

The pipeline, which supplies drinking water to more than 500,000 people in southwestern Ontario, draws water from the Lake Huron water treatment plant near Grand Bend to the terminal reservoir just north of London. Constructed of 1200mm (48-inch) prestressed concrete cylinder pipe (PCCP), the Lake Huron-to-London pipeline has ruptured four times, most recently in 2012.

To mitigate the chance of a future catastrophic failure on such a critical line, the water authority for the Lake Huron Primary Water Supply System collaborated with Pure Technologies (Pure) to install an acoustic-based monitoring system, designed to ensure the success of the Region’s long-term comprehensive pipeline management program.

The $7.5 million upgrade to the Lake Huron-to London water line is part of $179.1 million in water safety infrastructure investments across Southwestern Ontario.

SoundPrint® AFO Fiber Optic wire

SoundPrint Acoustic Fiber Optic technology tracks and records pipeline deterioration

Pure’s SoundPrint Acoustic Fiber Optic (AFO) monitoring technology is an industry-leading system that that listens, identifies and locates pipeline deterioration in real time. Once installed on a pipeline, the SoundPrint AFO system remotely detects the acoustic signature of wire breaks or “pings” in prestressed concrete cylinder pipe, and records their specific pipe location. If break activity increases, utility staff are alerted and can intervene on the deteriorating pipe in advance of failure.

Under the new system, “We will get an email to say a section of pipe has a break, and they even give us the map location of where it happens,”

John Walker

Operations Manager, Lake Huron and Elgin Area Primary Water Supply

The AFO system remotely detects the acoustic signature of breaks in the pipeline structural reinforcement and records the specific pipe location of the deterioration, alerting operating staff who can intervene in advance of a catastrophic failure of this regionally significant water transmission pipeline.

“A snapping wire or two won’t sound an alarm bell,” says Heather Edwards, project manager at Pure. “But when our monitoring team listens and identifies a large number of pings from wires breaking in a concentrated location, that’s when we focus attention on the acoustic anomalies to determine whether remedial action needs to take place.”

By managing their pipelines with innovative technologies, utilities can save millions of dollars

The project was special for Pure as it showcased the innovative SountPrint AFO technology upon which the company was founded more than 20 years ago.

“We love partnering with forward-thinking utilities like London Region to save money by using innovative technologies like the AFO system,” said Mike Wrigglesworth, senior vice-president of Pure Technologies, who spoke at the ceremony. “Instead of budgeting for an expensive replacement program or dealing with disruptive bursts, London Region has saved millions of dollars by actually managing their pipeline.”

Pure surpasses 700 miles (1,100 km) AFO monitoring milestone

Globally, Pure has surpassed 700 miles (1,100 km) of active AFO monitoring. Currently within North America and China, Pure monitors 56 mains from a combined total of 17 clients, including London Region. Pure’s active AFO system has recorded more than 43,600 wire breaks from its managed roster of pipelines located in North America and China alone.

With the installation of AFO technology in place, the London Region utility ensures active management of their most valuable buried assets, for the life of the asset.

That’s a comforting thought, well worth celebrating.

With stories of broken mains and aging infrastructure attracting more public attention, pipeline owners face difficult questions about long-term planning for their water and wastewater linear assets. In particular, when and where to focus renewal funding to service these aging networks.

However, as pipeline owners know, precise answers aren’t easy, especially without good data to back up an assumption. Lack of accurate and precise data can lead to an expensive guessing game when trying to identify high risk assets for renewal.

It has been suggested that over 70 percent1 of replaced pipe still has remaining service life. Therefore focusing on collecting the right condition data to make the right decisions at the right time is critical in making the most out of budgets.

Pipeline owners leverage data to make better decisions

We live in an era of big data, and with the help of Pure Technologies, many pipeline owners are beginning to understand how to leverage this data to make better decisions.

Data-based decision making can be used throughout the lifecycle of a pipeline asset to get a clear understanding of the current pipeline condition and its remaining useful life.

Targeted testing results chart

Small amount of sampling data leads to large sampling error and uncertainty

Clear understanding starts with data collection that specifically targets samples along the pipeline. However, not all sampling data is created equal. For example, while a small amount of sampling data gives you some information, it also leads to large sampling error and uncertainty on the true overall condition of your pipeline. This is why so much pipe with remaining service life is replaced, as decisions are made from data with large sampling error and uncertainty.

On the other hand, a large number of samples leads to smaller sampling error, and when you combine less error with more data, higher confidence decisions can be made.

Small amount of sampling data leads to large sampling error and uncertainty

Clear understanding starts with data collection that specifically targets samples along the pipeline. However, not all sampling data is created equal. For example, while a small amount of sampling data gives you some information, it also leads to large sampling error and uncertainty on the true overall condition of your pipeline. This is why so much pipe with remaining service life is replaced, as decisions are made from data with large sampling error and uncertainty.

On the other hand, a large number of samples leads to smaller sampling error, and when you combine less error with more data, higher confidence decisions can be made.

Colored candies and broken pipe

Using coloured candies to understand distribution principle

One way to demonstrate this principle is to examine a bag of colored candies. If you randomly sample a few pieces of candy from the bag, you would be uncertain about the proportion of blues to reds to greens because you don’t know the actual colour distribution.

However, if you were to increase the number of samples, and group this data into color bins, you would begin to have more clarity and understand the distribution of colored candies.

Coloured candies distribution chart

The more samples, the more certainty in the distribution data

In a way, this same principle of sampling applies to collecting pipe condition data. Sample size is important, and the more targeted samples you take, the more certain you are in the distribution of data. This provides owners with more confidence to make good decisions relating to renewal strategies.

That’s where Pure Technologies can help, with innovative technology and expert analysis that delivers precise data. This actionable information helps owners make confident decisions on the management of their pipelines.

Overall, it pays to invest in better data to better understand the true condition of your pipeline. True power lies in balancing the cost of data collection against the cost associated with uncertainty, and the more confident you are in your data, the more certain you are in your decision making, especially when making high-cost pipeline management decisions.

1: Patterson, J. and Phinney, T. (2008). “Assessing aging cast and ductile iron force mains.” Proc., Underground Construction Technology (UCT) Conference, Atlanta, GA, Jan.

 commissioning of a 50 km AFO system on the Lake Huron Water System’s water main transmission pipeline

Last week, government officials, special guests and educators gathered in London, Ontario to celebrate the successful funding, installation and commissioning of a 50 km AFO system on the Lake Huron Water System’s water main transmission pipeline – a 1200mm diameter PCCP supplying more than 500,000 people in southwestern Ontario.

Optic Fiber inside a pipe and Press Conference

“The project was special,” said Mike Wrigglesworth senior vice-president at Pure. “We love partnering with forward thinking utilities like London Region to save money by using innovative technologies like the AFO system. Instead of budgeting for an expensive replacement program or dealing with disruptive bursts, London Region have saved millions of dollars by actually managing the pipeline.”

The event was covered by the London Free Press, which wrote the following story.

Water supply safeguard comes down the pipe

Now, we can keep an ear out for problems with a pipeline that brings fresh water to London. The city and region took the wraps off a new, fibre-optic cable installed in the water pipeline from Lake Huron to London with an announcement Friday at London Convention Centre.

If that pipe is about to break or leak, new monitoring technology will warn water watchers, preventing a ­rupture.

“We have an acoustic fibre-optic system that allows pipelines to be managed, identifying problems before they become bigger. When a pipeline fails, it is a big mess,” said Mike Wrigglesworth, senior vice-president of Pure Technologies, the Alberta firm supplying the cable.

Staff members behind an open pipe

The $7.5-million project has installed the acoustic cable on a 50-kilometre stretch between the Grand Bend water treatment plant and an Arva reservoir, covering seven municipalities, which are sharing the cost with Ottawa and the province.

The acoustic cable lets staff “listen” to the pipeline for steel wires snapping as the pipe breaks down. There are hundreds of such wires in each section of pipeline.

“One wire breaking in a pipe is no big deal, but 30 or 40 is a weak section of a pipeline,” Wrigglesworth said.

“It can inform which sections of pipe are deteriorating, in real time, and we can be pro-active,” said Wrigglesworth. “We can identify which sections of pipe have a problem and make a plan to repair.”

A repair might cost $75,000, a “huge savings” over the cost of fixing a rupture, which could run to as much as $1.5 million, he said.

The Lake Huron-to-London pipeline has broken twice, in 2010 and 2012.

Under the new system, “We will get an email to say a section of pipe has a break, they even give us the map location of where it happens,” said John Walker, operations manager for the Lake Huron and Elgin area primary water supply, which oversees the regional and city water system.

“At some point, we will have to extend this (acoustic cabling) to Lake Erie,” Coun. Harold Usher said of the city’s other water supply pipeline. “Everything we do in one, we will do in the other. We cannot have farmer fields flooded.”

The $7.5-million upgrade to the Lake Huron-to-London water line is part of $179.1-million in water safety infrastructure investments across Southwestern Ontario. The federal and provincial governments are paying about $50 million each, with municipalities picking up the balance. In all, eight projects will be completed by 2017.

Celebration Cake

In preparing for its water future, the Region of Peel (Peel) adopts a unique assessment strategy for a newly constructed potable water transmission main that extends deep underground through the heart of Peel Region. The effort is paying off, with Peel decision makers gaining a better understanding of this pipeline as it comes into service.

Working on a new potable water transmission main

Peel Water & Wastewater services approximately 1.3 million residents and 88,000 businesses in Brampton, Caledon and Mississauga. The Hanlan Water Project is the largest water pipeline capital initiative ever undertaken by Peel, with a cost of approximately $500 million. The completed transmission and sub-transmission mains included in the Hanlan Water Project will serve Peel’s growth projections for the next two decades.

The project includes 15 km of 2400mm (96-inch) PCCP water transmission main. Construction began in 2011 and is scheduled for completion by 2017. The project is split into three contracts and construction includes both tunnelling and open-cut methods.

Outside and inside a tunnel

Some pipeline sections tunneled in excavated depths of 50 meters

The project is unique from the point of view that the majority of the pipeline will be built under existing infrastructure, with some sections of pipeline tunnelled in excavated depths up to 50 meters (150 feet).

Peel has encouraged the use of technology and innovation throughout this project and has included innovative assessment strategies by Pure Technologies prior to pipeline commissioning. Baseline condition assessment and real-time monitoring technologies have offered value, and peace of mind to Peel managers and decision makers involved with this project.

SoundPrint® acoustic fiber optic (AFO) inside a pipe

Acoustic monitoring versus electromagnetic inspection technology

Pure’s baseline condition assessment includes visual inspection, 3D inertial mapping, electromagnetic (EM) inspection where applicable and SoundPrint® acoustic fiber optic (AFO) monitoring the pipeline during hydrostatic pressure testing of the pipeline. The project includes a continuous monitoring solution once the pipeline is commissioned into service, expected in 2017.

AFO monitoring is an innovative monitoring technology for identifying wire breaks in PCCP pipes. Unlike EM, which identifies the number of wire breaks that exist at a point in time, acoustic monitoring identifies the number of wire breaks that occur during the monitoring period, effectively identifying the location of active deterioration for the lifespan of the asset.

By ‘listening’ for wire breaks, pipes that are approaching failure can be identified and rehabilitated. With the installation of AFO technology at the time of construction, Peel ensures active management of their most valuable buried assets, for the life of the asset.

“A snapping wire or two won’t sound an alarm bell,” says Adam Koebel on behalf of the Data Analysis Group at Pure. “But when our monitoring team notices a large number of pings from the wires breaking in a concentrated location, that’s when we focus attention on the acoustic anomalies to determine whether remedial action needs to take place.”

The project was split into 3 contracts with varying scope per contract

The 15 km of 2400mm PCCP project was split into 3 contracts with different general contractors, and complimentary scope per contract.

Pipeline construction along a road

The acoustic monitoring covered a distance of 1,138 meters and spanned a total of 132 pipe sticks. Analysis of the data recorded during the pipeline monitoring found two (2) acoustic anomalies consistent with wire wrap breaks, which amounts to a negligible amount of change or distress. Pure conducted a second (post pressure test) EM scan to confirm the AFO testing and determine the presence of pipe wall distress.

Contract 1 (underway) includes visual inspection and mapping

Pure’s involvement in Contract 1 began in 2016, with a visual and sounding inspection of 5.87 km of the 2400m PCCP pipeline and included identifying potential joint defects and other signs of distress, as well as verifying lay schedule from within the pipe. AFO monitoring will let Peel and their contractor know if any distress occurred during hydrostatic testing.

Contract 3 is on schedule to wrap-up in 2017, while Contract 4 scope of work will include final disinfection and commissioning of the new feedermain.

Once a baseline condition has been established, the AFO system will allow Peel to track the deterioration rate and identify at-risk pipes before they fail.

For Peel, acoustic fiber optic monitoring is like preventative medicine, and as a safeguard, it’s proven to work.

Fiber optic

24-Detector PipeDiver tool

Advanced PipeDiver tool developed for condition assessment of metallic pipes.

Pure Technologies (Pure) never says no to an engineering challenge. If a client has a particular pipeline assessment or monitoring challenge to overcome in order to make a rehabilitation decision, we’ll do whatever it takes to help our clients solve the problem.

Pure Technologies embraces research and development (R&D), with a strong dedication to continually develop new technologies and improve upon existing inspection systems. This attitude of taking a winning platform and making it better was demonstrated again with the introduction of the optimized PipeDiver, an advanced, multi-sensor tool developed specifically for the condition assessment of metallic pipes within pressurized pipe networks.

PipeDiver inspection tool operates while the pipeline remains in service

As a technology platform, PipeDiver is a versatile, free-swimming condition assessment tool that operates while the pipeline remains in service, often providing an easier and less costly alternative than inspection methods that require a shut-down or dewatering.

Two men working with a PipeDiver device

The PipeDiver platform is ideal for critical, large-diameter lines that cannot be removed from service due to operational constraints or lack of redundancy. The PipeDiver tool requires only a 12-inch access, and can be deployed on pipelines that range from 16 inches up to 120 inches.

The tool can be deployed, collect information on pipeline condition and extracted in a single mobilization.

As the PipeDiver platform can be equipped with a closed circuit television (CCTV) camera, the tool is able to record and deliver video images from the inside of the pipeline (quality depends on water clarity).

PipeDiver Cammera working

Tool able to navigate most butterfly valves, tees and pipeline bends

To begin an inspection, the tool is balanced to be neutrally bouyant and inserted into a pressurized or depressurized pipeline through a tap connection, or an existing access point. The tool travels with the product flow, and utililzes flexible petals to navigate butterfly valves, tees and bends in the pipeline.

Originally designed for use in pressurized concrete cylinder pipes (PCCP), the tool has specialized electromagnetic sensors (PureEM) to identify and locate broken prestressing wire wraps, (one of the main structural components and failure modes of a prestressed concrete pipe).

Historically, technologies available to assess the condition of metallic pipe have been full diameter tools (“Smart Pigs”) unable to traverse most water or wastewater pressure pipelines due to inline valve restrictions and limited access for insertion and retrevial of a full diameter tool. These challenges led Pure’s R&D to develop the specialized PipeDiver for metallic pipes, equipped with advanced electromagnetic technology to identify localized areas of wall loss.

The PipeDiver electromagnetic (EM) technology can also be used in bar wrap pipelines to identify broken bars and steel cylinder damage, the two main structural components bar wrap pipe.

PipeDiver device inside a pool of water

Utilities Kingston welcomes PipeDiver to assess its metallic pipeline

Since its introduction, the optimized PipeDiver platform has been deployed for various projects in Europe, Canada and the U.S.

This year Utilities Kingston agreed to pilot the new technology as part of a comprehensive condition assessment on its Dalton Avenue (North End) Pump Station Force Mains. The pipelines are both approximately 1,550 meters long and follow a parallel route for approximately 1 kilometer.

The older of the two force mains is 450 mm (18-inch) in diameter, constructed of ductile iron built in the late 1950s, and had failed several times over its lifetime. The newer of the two force mains is 600 mm (24-inch) in diameter, built from an unspecified concrete pipe from the early 1960s. As the pipe material specifics were still unknown at the time of the inspection, the Pure elected to conduct a PipeDiver run to accommodate both possible types of pipe material – assumed by all to be bar wrapped pipe (BWP) and prestressed concrete cylinder pipe (PCCP).

Force main defects can vary from one pipe material to another

During a forensics exercise on the 600 mm force main using earlier PipeDiver technology, it was revealed that the actual pipe material included 102 suspected metallic pipes, which were not identified as such in the original plan and profile drawings.

This included ductile ironsteel and unexpectedly, reinforced concrete pipe (RCP), which is not usually used in pressurized environments. Electromagnetic inspection of the RCP can only reveal anomalies on the circumferential cage and not the longitudinal bars.

Inserting the PipeDiver device through an inspection hole

Optimized PipeDiver tool deployed in wastewater

Pure deployed its optimized PipeDiver tool to conduct a quality analysis of the 450 mm pipe. The purpose of the inspection was to locate and identify steel and ductile iron pipes that have indications of wall loss.

This marked the first condition assessment of metallic pipe using the optimized PipeDiver in wastewater, an exercise that confirmed the validity of the tool’s sensor technology.

Results lead to actionable information regarding rehabilitation

Of the 650 pipes inspected with the PipeDiver tool, a total of 55 pipes in the 450 mm Dalton Avenue Pump Station Force Main had electromagnetic anomalies characteristic of localized wall loss.

The data collected gave Utilities Kingston a better understanding of their real, not assumed assets. The results, which included a DIP risk of failure analysis, were used to complete a structural evaluation of the force mains, and have provided UK with actionable information regarding any necessary repairs or rehabilitation.

PipeDrive device revision after the inspection has finished
City of Vancouver from the air

With its Pacific Ocean entranceway and towering backdrop of snow-dusted mountains, it’s no wonder the City of Vancouver ranks among the most laid-back, beautiful cities in Canada, and indeed, the world. Water is in its blood.

This spring the coastal seaport city retained the services of Pure Technologies (Pure) to perform a condition assessment and risk analysis of the Powell-Clark Feeder Main, part of the city’s water system that daily delivers 360-million liters of high-quality water throughout the city. During the course of the assessment, the inspection team had to deal with unexpected challenges, but in true West Coast spirit, collaboration between the inspection teams led to success.

Over five days in March 2016, Pure performed an electromagnetic inspection of the subject pipeline utilizing its free-swimming PipeDiver® platform, and an acoustic inspection using its free-flowing SmartBall® inspection tool. Pure also monitored this feeder main using a Transient Pressure Monitor for three months prior to the previous two inspections.

PipeDiver device

PipeDiver inspection identifies electromagnetic anomalies

The Powell Street Feeder Main is comprised of prestressed concrete cylinder pipe (PCCP), ranging from 750 to 900-mm in diameter. The Clark Drive Feeder Main consists of 750-mm of bar wrapped pipe (BWP).

The PipeDiver electromagnetic inspection covered a cumulative distance of 4.57 kilometers and spanned 676 pipes. Unlike more restrictive assessment tools, PipeDiver is a flexible, free-swimming tool that flows with the product and is able to easily navigate through most butterfly valves, apertures and bends in the pipeline, delivering electromagnetic (EM) data for a variety of pipe type and materials.

EM technology provides prestressing wire-break estimates on each individual section of PCCP, which is the best indicator that this type of pipe will fail. This allows for one deteriorated pipe to be identified within an entire pipeline that is in good condition overall, and also provides the baseline condition on all pipes in the inspected distance.

Analysis of the data obtained during the inspection determined that one (1) pipe (less than one percent of the pipeline) in the 750 mm Powell-Clark Feeder Main displayed electromagnetic anomalies consistent with 30 broken prestressing wire wraps. This is well below the average distress rate observed by Pure Technologies in PCCP pipelines, which is 3.8 percent of pipes in structural distress.
SmartBall with case and insertion tools

SmartBall inspection tool used to locate leaks and gas pockets

In addition to the EM inspection, Pure also performed a SmartBall inspection to identify and locate leaks and pockets of trapped gas along the pipeline.

Unlike traditional external listening tools with limited success on large diameter pipes, free-flowing SmartBall technology provides a high degree of accuracy, since as the ball rolls, it can inspect every inch of a water main to detect leaks and gas pockets.

The SmartBall tool was inserted into the pipeline through a flange access and acoustic and sensor data was collected and recorded as the tool traversed the pipeline. At a distance of 5.8 kilometers, (only 470 meters from the end of the inspection run), the tool stopped tracking.

Crews from the City and Pure put their heads together to solve the problem.

ROV camera shows a tool cart inside the pipe

Collective thinking clears the debris and all is well

By analyzing data from the earlier PipeDiver inspection, Pure determined that unknown debris likely lodged the SmartBall tool.

The City excavated and modified a tap to allow Pure to access the pipeline with a submersible ROV (equipped with a camera) to retrieve the SmartBall tool and examine the debris, which turned out to be an old forgotten tool cart. The cart and SmartBall tool were extracted, the data was evaluated and considered valid, and all was good.

From the SmartBall data, Pure Technologies detected three (3) anomalies characteristic of leaks and zero (0) acoustic anomalies characteristic of pockets of trapped gas.

While no gas pockets were identified during this inspection, two (2) instances of entrained air were identified as migratory acoustic anomalies, and flagged for future inspection, as they may develop new pockets of trapped gas.

Validated results help the City manage its infrastructure

In spite of the cart debris blocking the SmartBall tool during the last few meters of its long inspection journey, the data collected during the pipeline assessment was analyzed as valid.

When combined with the results from the PipeDiver EM inspection, the condition data will be used as part of the City of Vancouver’s asset management initiative and allow for proactive measures in the assessment and management of their infrastructure.

Over the past decade, several high profile oil and gas pipeline failures have shown that the consequences of a rupture can be extremely severe for both the environment and human life, and can result in billions of dollars in remediation costs. Because of all these negative consequences, governments have made it mandatory to conduct routine inspections on these assets to prevent catastrophic events.

Today, the most common form of pipeline assessment is inline inspection (ILI) with smart pigs. These pigs flow with the product, collecting data on the condition of the pipe wall. When these tools are operating in a live pipeline, it is important to track their precise location and speed, as a lost or stuck pig can obstruct product flow, cause unwanted service disruptions or damage the pipeline.

A common misconception about pig tracking is that a run always goes as planned.  In the majority of runs, nothing unexpected will occur, but there have been a few cases where a minor event can quickly derail the smoothest of jobs, resulting in cost escalations and unnecessary hassle for the pipeline owner. By taking proper precautions and using advanced tracking technology, pipeline owners can ensure that they are prepared for any unexpected event that may occur.

Traditionally, pigs have been tracked by a single technician equipped with a standard geophone to identify the pig passing. This method can be extremely challenging and unreliable, and can result in a lost pig. In order to mitigate the risks of conventional tracking, owners can use remote tracking technology which provides greater reliability and accuracy.

Remote Tracking Prepares Asset Owners for the Unexpected

Remote tracking combines above ground markers (AGMs) equipped with multiple sensors with remote communication technology. This ensures that the pig is being tracked using more than one sensor, which is significantly more reliable than a standard geophone. In addition to tracking with multiple sensors, pipeline owners and ILI vendors are provided with a record of each passage that is downloaded from the AGMs. This record shows the signal of the pig passage, along with other information such as time and speed. The AGMs provide snapshots into a software where they can be used for real-time tracking of the pig’s position, speed, and estimated time of arrival. Pipeline owners can be sure that the results are accurate because the AGMs constantly record data to confirm pig passages when they are turned on.

If a pig gets stuck, the AGMs will know if the pig has not passed a tracking location, making it much easier for field technicians to retrieve it in a timely manner, so no damage is caused to the pipeline. Remote tracking provides reliable information and when unexpected events occur, enables pipeline owners to be better prepared for any issues that may arise.

To learn more about remote tracking and its benefits, download the white paper below.

Sensor with remote communication technology

*Published in World Pipelines Magazine

Oil and gas pipelines have been around for well over a century, and some of the earliest constructed are still in service today.  Although early pipelines were made of wood, and in the past few decades plastics and composite materials have increased in popularity, the vast majority of pipelines in service today are constructed with steel.

Like any pipe material, steel pipe has its downfalls. Steel has a propensity to dent, buckle, corrode and crack when exposed to the environment.  Steel pipeline’s carrying combustible hydrocarbons are buried underground with typically ~1 meter (3 feet) of cover to protect them.  In order to mitigate corrosion, pipelines are covered with a protective coating, utilize cathodic protection (CP), and have their pressure regulated to reduce crack formation and propagation.

Despite all of the design innovations made over the past century, it has not been enough to prevent failures – even the most recently constructed pipelines.  Weather cycles, frost heaves, and road loadings cause physical damage to the pipeline and protective coating.  Operational errors and material defects cause the steel to succumb after years of relentless pressure cycles from the pipeline product itself.  Therefore, proactive pipeline inspections are needed to identify defects, before they cause a leak or rupture.

Pipeline integrity can be validated and assessed using three primary techniques: hydro-testing, the use of Inline Inspection (ILI) tools, and Direct Assessment.

Hydro-testing

Hydro-testing became common practice for pipelines in the 1940s. The process involves taking the pipeline out of service and purging the product, then the pipeline is pressurized above the maximum operating pressure (MOP) with the intent to determine the ability to operate the pipeline at MOP.  While hydro-testing is still widely used today, there are several drawbacks to the process. The water used in hydro-testing is considered hazardous material after being used, meaning owners incur the additional risk and cost associated with disposing of the water after testing. The information gained from the test is also limited in that it provides no information of the actual condition of the pipe, coating, or surrounding environment.

Hydro-testing can also promote internal corrosion of pipelines, especially if the water used is not properly treated for microbiologically influenced corrosion (MIC) and chlorides. Internal corrosion usually occurs if the pipeline is not properly cleaned and dried after the test.  Hydro-testing can also result in pressure reversals, which worsen the integrity of the pipeline [1].  Finally, the pipeline may be required to be out of service for a significant amount of time, resulting in a significant loss of revenue.

Inline Inspection

ILI tools – which are commonly referred to as smart pigs – were developed in the 1960s and commercialized in the 1970s.  These tools are designed to survey the conditions of the pipeline wall with limited disruption and can identify and quantify the corrosion and cracking in steel pipelines [2].  Magnetic flux leakage (MFL) and ultrasonic testing (UT) are common ILI tools used widely by owners today.

ILI is a significant part of pipeline integrity management, and promote safe, efficient and cost-effective pipeline operation [2].  However, it is important to remember that ILI is just a subset of a family of inspection tools used to verify pipeline fitness for service.  As with any inspection technology, ILI tools have a threshold for detection – the tools are unable to reliably detect anomalies that are below their design specifications’ detection ability. Also, internal pipeline inspections are primarily reactive, requiring the damage or wall loss to occur before defect detection is possible.

Direct Assessment (DA)

The most recently developed solution for pipeline integrity management is Direct Assessment (DA), which is a structured, iterative integrity assessment protocol used by pipeline operators to assess and evaluate the integrity of their pipelines.

Adoption and demand for DA is increasing in modern integrity programs due to more stringent industry regulations, aging pipeline networks, limitations of alternate inspection techniques, and the fact that roughly 70 percent of pipelines within North America are difficult to pig.  Direct assessment surveys provide pipeline owners with important information on both the pipeline’s condition and its surrounding conditions, both of which can lead to degradation and eventual failure.

The Stages of Direct Assessment

It should be noted that geotechnical, dent, and buckle threats are not specifically addressed with any of the DA techniques.  All DA protocols are four-step iterative processes which include a Pre-Assessment, an Indirect Inspection, a Direct Examination and a Post-Assessment.  Inspections involve the integration of as much pipeline available integrity data as possible, which includes physical characteristics and operational history, historical and multiple indirect inspections, and direct pipe surface examinations.

In the pre-assessment step, historic and current pipeline data is collected to determine whether DA is feasible, define DA regions, select indirect inspection tools and determine if additional integrity data is needed.

The second step in DA methodology involves the use of non-intrusive and aboveground techniques. These tools assess the effectiveness of the coating and cathodic protection for pipeline external corrosion assessment (EDCA an ECCDA), and predictive modelling, or critical angle calculations for pipeline internal corrosion assessment (ICDA) to identify and define areas susceptible to internal corrosion.

For external corrosion assessment, the state of cathodic protection, coating and soil resistivity are critical factors in determining high-risk areas. For internal corrosion assessment, fluid flow, mass transfer, solid accumulation, mineral scales, corrosion products, and MIC are critical components [3].  For stress corrosion cracking, critical factors include operating stresses, operating temperatures, distance from a compressor station, age of the pipeline, and coating type.

The direct examination step involves the analysis of pre-assessment and indirect inspection data to select sites for excavation and examination of pipe surface. This process validates the inspection data and provides a first-hand evaluation of the pipe surface and surrounding environment.

Finally, the post-assessment phase involves the analysis and integration of integrity data collected from the previous three steps to assess the effectiveness of the DA process and determine the necessary reassessment intervals.

There are six DA standards developed by National Association of Corrosion Engineers (NACE) and they include:

2002 -NACE SP0502-2010 ECDA (External Corrosion Direct Assessment)

2004 -NACE SP0204-2008 SCC-DA (Stress Corrosion Cracking Direct Assessment)

2006 -NACE SP0206-2006 DG-ICDA (Dry Gas Internal Corrosion Direct Assessment)

2008 -NACE SP0208-2008 LP-ICDA (Liquid Petroleum Internal Corrosion Direct Assessment)

2010 -NACE SP0110-2010 WG-ICDA (Wet Gas Internal Corrosion Direct Assessment)

2010 -NACE SP0210-2010 ECCDA (External Corrosion Confirmatory Direct Assessment)

DA is also covered in ASME B31.8S (Section 6.4).  In the United States, DA is covered in US Code of Federal Regulation CFR 49 Part 192.923 (for natural gas pipelines) and 195.888 (for liquid hazardous pipelines).  It is now one of the three accepted inspections (ILI and Hydro-testing being the other two) allowed for oil and gas pipelines.

Identifying Pipeline Anomalies Using Directing Assessment

When completing a DA inspection, there are three types of anomalies that owners are aiming to identify:

1.         External Corrosion (EDCA and ECCDA)

2.         Internal Corrosion (dry gas, wet gas, and liquid petroleum ICDA)

3.         Stress Corrosion Cracking (SCCDA).

Due to the serious consequences of corrosion and leaks in underground pipelines, external corrosion direct assessment (ECDA), and external corrosion confirmatory direct assessment (ECCDA) – as described in ANSI/NACE SP0502 and NACE SP0210 – were developed in an attempt to proactively prevent external corrosion and ensure the integrity of oil and gas pipelines that are difficult to pig.

ECDA is a continuous improvement process intended to identify and address locations at which corrosion activity has occurred, is occurring, or might occur. For instance, ECDA identifies areas where coating defects have already formed, and can ascertain where cathodic protection is insufficient and corrosion is possible, before major repairs are required.

The success of any ECDA requires strong knowledge of the soil/environment, pipeline material, coating, cathodic protection, and foreign/interference current on the pipeline. Also, the accurate selection of susceptible areas for external corrosion relies on using at least two complementary advanced aboveground inspection techniques. These aboveground indirect inspection techniques may include: direct current voltage gradient (DCVG) or alternating current voltage gradient (ACVG) surveys, a cathodic protection close interval potential survey (CP CIPS), alternating current—current attenuation (ACCA) and side drain (for bare or ineffectively coated pipelines) surveys. Normally these aboveground inspections are used in conjunction with pipe locating.

The development of internal corrosion in pipelines is partly because of its complex nature and interaction between constituents that are found in transported gas and liquid products (e.g., oxygen, carbon dioxide, hydrogen sulfide, chloride, bacteria, etc.). When in the presence of water, these contaminants can lead to conditions conducive to the occurrence of internal corrosion. The susceptible locations for internal corrosion are usually where liquids, solids and gas accumulate. In order to ensure that susceptible locations along the pipeline are prevented from internal corrosion, internal corrosion direct assessment methodology is implemented.

Internal Corrosion Direct Assessment (ICDA) methodology has been developed to verify pipeline integrity, especially for pipelines that are not able to accept inline inspection (ILI) tools. ICDA includes Wet Gas Internal Corrosion Direct Assessment (WG-ICDA), Dry Gas Internal Corrosion Assessment (DG-ICDA) and Liquid Petroleum Internal Corrosion Direct Assessment (LP-ICDA). WG-ICDA (NACE SP110-2010) is used in pipelines that assumes that water, or a combination of water and hydrocarbons can be present in the pipeline. It is intended for onshore and offshore systems where liquid to gas ratio is small. It tends to identify locations in the pipeline where corrosion is expected to be severe. DG-ICDA (NACE SP206-2006) is applicable to pipelines that transport gas that is normally dry, but may suffer infrequent upsets, which may introduce water to the pipeline. LP-ICDA (NACE SP208-2008) is employed to assess the susceptibility of internal corrosion on pipelines that transport incompressible liquid hydrocarbons that normally contain less than 5 percent base sediment and water. The success of any ICDA process is dependent on using an accurate corrosion model to predict a precise elevation profile in order to determine susceptible locations for internal corrosion.

DA technology has also proven successful in stress corrosion cracking direct assessment (SCCDA), offering pipeline operators a comprehensive pipeline integrity management portfolio. SCCDA (referenced in NACE SP0204-2008 and ASME B31.8S) is a proactive structured process that seeks to improve pipeline safety by assessing and reducing the impact of stress corrosion cracking. Stress corrosion cracking can occur at neutral or high pH when susceptible pipeline material is exposed to stress, specific susceptible temperature, and a corrosive environment.

The Benefits of Direct Assessment

Direct Assessment is non-intrusive and inspections can be completed during normal operation of the pipeline.  DA is also a proactive integrity management tool that can find anomalies before they become critical defects, while traditional ILI tools are reactive in that they identify existing pipeline damage.

While hydro-testing and ILI tools are an important part of integrity management, the development of DA provides pipeline owners with another solution to identify at-risk areas of pipe before they become a major problem. A combined integrity approach that employs DA can help pipeline owners ensure containment and prevent costly, reputation-harming pipe failures.

References

1.    Pipeline Research Committee, American Gas Association, NG-18 Report No. 111 (Nov. 3, 1980)

2.    NACE 35100, In-Line Inspection of Pipelines, NACE International, May 2012

3.    NACE Training Course, Direct Assessment, NACE International, November 2012

*Published in World Pipelines Magazine

The oil and gas pipeline industry has been under close scrutiny for a long time. It leads the way as one of the most regulated industries in the world, and for good reason.  With so many safety-related, social and environmental factors at stake, comprehensive regulation ensures rigorous standards for the design, construction, operation and maintenance of O&G pipeline systems.

Global economics and political activism also play a role in shaping today’s conversation about pipelines. In North America, public debates about the Keystone XL Pipeline have dominated much of the recent news, compelling operators to vigorously participate in the discussion and advocate their integrity management programs. Although Keystone has been put on hold, social capital can assist in getting projects of this magnitude on the radar again.

Through it all, much of the dialogue has focused on the industry’s commitment to protecting communities and the environment from risk by means of rigorous pipeline integrity management programs. As a result, the requirement for increased pipeline safety drives innovative research into improving the sensitivity and reliability of inline inspection (ILI) tools.

Most operators already deploy trusted inline technologies that detect structural deterioration and help maintain pipeline integrity. However, with pressure mounting from stricter regulation, increased operational costs, commodity price-driven budgetary pressure, and often limited available resources, operators face an increasing number of challenges, including vigilance from highly engaged consumer groups.

Although the pressure to perform is greater than ever, operators are responding appropriately with greater confidence in modern technologies to assist in the operation and monitoring of their pipeline systems.

Better ILI tools instill better confidence in containment

To have confidence in the pipeline, operators must have confidence in the capabilities of ILI tools to detect small anomalies that could lead to potential failures.  They must also trust the reliability and interpretation of the data, knowing with as much certainly as possible that the depth, size and location of the pipe wall anomaly is correct.

Overall the news is good. Between 2002 and 2013, Canadian Energy Pipeline Association (CEPA) member companies were able to transport oil and natural gas with a 99.999 percent safety record. While that statistic sounds impressive, headline-grabbing pipeline incidents do occur, (in 2014 there were 122 natural gas and liquid releases) and when that happens, the repercussions can undo years of containment management trust and goodwill.

While the oil and gas industry boasts a remarkable safety record, a reliance on conventional tools limit the near perfect record.  As much as the technologies have been refined, regulators have noted that inline inspections don’t pick up all defects, and expedient follow-through often depends on the people analyzing the data and planning repairs, a process that can take months.

“Despite their sophistication, the detection capabilities of inline inspection tools have limitations,” the US National Transportation Safety Board noted in its report on the 3.3-million-liter 2010 spill in Michigan.

Limitations of conventional ILI inline inspection technologies

The oil and gas pipeline industry has access to an extensive toolbox of technologies for robust integrity programs. Some tools address cracks or corrosion issues, while other tools focus on stress, pressure and product containment. Cost, resolution, reliability, data analysis speed – each technology has its own strengths and limitations, with no silver bullet as the single solution for collecting pipeline condition information.

For example, there is a strongly-held belief in hydrostatic testing as a reliable method to test a pipeline’s integrity. One of the earliest inspection techniques, hydrostatic testing determines if a pipeline can hold its operating pressure. A form of destructive testing, hydrostatic inspection involves purging the product, flooding the line with water, pressurizing it to a predetermined level and maintaining the pressure for a period. Based on the results, detected anomalies in pressure, volume and density can be a precursor to leaks.

Critics however, argue and have quite effectively demonstrated that the hydrostatic tests lack the ability to monitor ongoing corrosion or cracking and that the high pressure environment can exacerbate previously small defects, increasing risk of future rupture.

Smart pigs for detecting large cracks and corrosion

Unlike hydrostatic testing, which is often conducted on pipelines for acceptance testing or for pipelines recently rehabilitated, pigging is the more commonly accepted method of testing pipeline integrity.

While newer “smart” pigs have an excellent reputation for accuracy, their efficacy is often limited to detecting corrosion and cracking that exceeds the threshold for detection of the technology.  Small corrosion pits and cracks, especially cracks grouped in a colony, can pose a challenge to most conventional ILI pigging devices.

The various ILI technologies are sensitive to axial or circumferential defects, and each has limitation for minimum aspect ratios or cross sectional wall loss area before the ILI tool can report the anomaly.  It is also possible to have cracks and wall loss pits that are in close proximity to girth welds, long seams, and other features in the pipe, which can mask the defect, preventing the ILI tool from properly identifying and sizing.  As a result, it is possible to have leaking cracks and corrosion pits that are too small to be sized and reported from conventional ILI.

Not all lines are piggable

Some pipes are more suitable for pigging than others. While most oil and gas transmission lines were built in long straight sections suitable for pig runs, sections with small diameter pipe and small bend radius pipe configurations can limit many ILI tools.  Lines with expansion loops and miter bends, and in the case of natural gas lines, those with reduced port valves, are factors that can prohibit or restrict the traversing of online tools.

Mass balance measurement and other leak detection tools

To make up for the limitations of conventional ILI technologies, operators often deploy measurement methods and leak detection technologies to complement their integrity programs.

Mass balance is a means of detecting leaks by measuring the mass of product entering the pipeline compared to the mass exiting the pipeline. The limitation for detecting small leaks is the sensitivity of the mass meters being used (2-4% accuracy for conventional orifice meters and 0.25% for turbine meters), and the fact that the product temperature and pressure changes as it moves through the pipeline.

While mass balance is a means to determine leaks, it is also recognized that making actual measurement of mass from volume (through a meter) at different temperature and pressure going in versus coming out of the pipeline, in real time, is difficult, and not very precise or sensitive to small leaks.

As a result, a leak has to release more product than the total tolerance of the mass balance system before a positive leak/release event is alarmed.

Acoustic leak detection

Minute cracks are often preliminary indicators of potential small leaks that produce acoustic emissions at levels often unrecognizable over background noise.

Acoustic leak detection can be conducted with geophones/hydrophones, comparators and acoustic fiber optic techniques, and each of these acoustic tools is subject to different background noise limitations to determine leak detection thresholds.  Not only can these tools have limitations to prevent small leak detection, the expense from installing permanent acoustic systems may reduce the practicality of these technologies.

Emerging technologies on the horizon

To complement hydrostatic testing, conventional pigging tools, and leak detection technologies, the oil and gas industry is evaluating a growing number of emerging external confirmation of containment technologies. These include vapour-sensor systems, hydrocarbon-sensing cables that change in the presence of hydrocarbons, internal pressure wave based tools and fibre-optic based systems that detect temperature changes and acoustic signals associated with leaks.

While these technologies offer hope for more precise surveys, they have yet to be universally accepted or proven. Many are still under development and often require economically impractical installation requirements.

However, there is an innovative, multi-sensor ILI platform that has been used in integrity management programs since 2006, gaining the attention of major pipeline players who have tested the platform, which has now been used on over 25,000 kilometers of pipeline in total.

Introducing SmartBall® technology for Oil & Gas pipelines

To provide a realistic snapshot of a pipe’s condition, many proactive operators are deploying SmartBall technology,  a free-swimming multi-sensor tool for long inspections of piggable and difficult to pig liquid and gas pipelines 4 inches and larger. This advantage makes the ball-shaped tool an excellent choice for traversing not just standard diameter pipes, but for smaller diameter liquid lines and for gas pipelines with loops and frequent sharp bends and heavy wall fittings.

During an inspection, the SmartBall sensors collect acoustic, pressure, temperature, magnetic and inertial data from inside the pipeline.

Primary applications for the SmartBall tool

SmartBall surveys can be conducted independently, at regular intervals, as part of a routine pipeline integrity management program, or as a value-add to inspection programs along with hydro-testing, ILI, or direct assessment.

The tool is launched and retrieved at existing pig traps and is tracked using proprietary acoustic receivers and/or Armadillo pig tracking boxes (AGMs). The location data from acoustic receivers and tracking boxes is used during data analysis to locate any anomalies.

SmartBall technology has three primary applications, and the multi-sensor tool can provide a variety of pipeline data.

1. Confirmation of Containment

Regular confirmation of containment surveys are an important part of integrity management as leaks are often a preliminary indicator of pipe failure.

Unlike conventional leak detection systems, confirmation of containment with SmartBall supplements these systems. The SmartBall tool directly passes leaks, and is therefore capable of detecting losses as small as 150 mL/min, which can be several orders of magnitude more sensitive than conventional methods.

SmartBall surveys can also complement regular ILI surveys by addressing potential pinhole anomalies that have aspect ratios below the reporting threshold of ILI systems.

2. Pressure and Temperature profiles

As the SmartBall is rolling and not sealing against the pipe ID, as conventional pigs do, the tool can also record precise pressure and temperature profiles. The SmartBall platform can be deployed in gas pipelines, where pressure and temperature profiles can be integrated into flow models to assess the points where water vapor may condense out of the gas.

The tool can also be used to assess the point where high temperatures from pump or compressor output may have affected the pipe coating, as well as in settings to validate and improve SCADA and mass balance systems.

3. Pipe Wall Assessment and Inertial Mapping

During inspection, the SmartBall Pipe Wall Assessment (PWA) tool collects magnetic data that can provide a screening of the pipe wall for stress resulting from features like large cracks, large wall loss, dents and points of excessive loading.  The test can also complement hydrostatic testing, as it can survey the pipeline before and after hydro-tests to identify stress that is indicative of pressure reversals.

In addition, the SmartBall PWA tool can produce a girth weld and joint tally for the pipeline, as well as can confirm locations of bends and general geometry of the pipeline.

Helping operators make better decisions

Admittedly, SmartBall is not designed to compete with high resolution technologies like Magnetic Flux Leakage (MFL), which can provide detailed wall loss data.

What SmartBall can do is complement other integrity tools by providing additional data sets to ensure pipeline integrity. In a single deployment, it can detect anomalies associated with pinhole leaks and stress that doesn’t necessarily involve wall loss; e.g. geotechnical strains.  It can also detect change in pressure and temperatures.

Ultimately, the SmartBall tool can help capture enough data to confirm the integrity of the pipe and give operators enough microscopic knowledge to make better, informed, risk-based decisions on the health of their pipelines.

City of Ottawa Skyline

When your inspection task is to survey a critical pipeline for leaks, nothing is more satisfying than trusting your technology to predict the leak location and then standing by as the client excavates the area to find a flow of water within one meter of exactly where you said it would be.

The above-described “leak-where-predicted” recently happened with the City of Ottawa, when Pure Technologies (Pure) deployed its SmartBall® inspection platform to locate leaks along a critical transmission main, as part of a long-term condition assessment program for the municipality. Over the past five years, Pure has used its suite of platform tools, including Sahara®PipeDiver®, and PureRobotics®, as well as the free-swimming SmartBall device, for deployment on the City’s ongoing Drinking Water Transmission Main Condition Assessment Program.

Transmission main comprised of 1220mm (48-inch) lined cylinder pipe

The City’s potable water distribution system consists of 3,728 km of both local water mains and large-diameter transmission mains that move large volumes of water throughout the capital. The City has approximately 230 kms of transmission mains ranging in diameter from 600mm to 1980mm, (24-inch to 78-inch) subdivided into 96 segments for the purpose of a risk-based prioritization.

For the subject project, the City of Ottawa retained the services of Pure to perform a SmartBall tool inspection to identify and locate leaks and pockets of trapped gas along the Baseline Road Water Transmission Main, a high priority pipeline. The 1220mm (48-inch) diameter pipeline is comprised of Lined Cylinder Pipe (LCP) mostly constructed in the 1970s.

Pipe leaking

SmartBall tool chosen for its ease of use and sensitivity to small leaks

The SmartBall tool was chosen as an inspection platform for its sensitivity to small leaks, minimal pipeline modifications required for insertion and extraction and ability to inspect long distances in one deployment. The free-swimming, acoustic-based SmartBall assembly is inserted into the flow of a pipeline, traverses the pipeline, and is captured and extracted at a point downstream.

SmartBall extraction process

During inspection, the SmartBall tool’s location is tracked at known points along the alignment to correlate the inspection data with specific locations. As the SmartBall tool approaches a leak, the acoustic signal will increase and crescendo at the point when the tool passes the leak.

For the City of Ottawa project, five (5) surface-mounted acoustic sensors were placed along pipeline to track the SmartBall tool during the inspection. SmartBall receivers were connected to the sensors on the pipeline at the locations indicated to track the tool during inspection.

The SmartBall device was inserted into the pipeline through a 100mm drain near a hospital. Acoustic and sensor data was collected and recorded as the SmartBall tool traversed the pipeline for more than three kilometers. The SmartBall was then extracted from a reservoir using a Remotely Operated Underwater Vehicle and data was evaluated to identify acoustic anomalies associated with leaks and pockets of trapped gas.

Verification with ground microphones turned up unexpected results

From the survey results, Pure detected one (1) acoustic anomaly characteristic of a leak and zero (0) anomalies consistent with pockets of trapped gas.

Although Pure was confident in the SmartBall leak detection data, sometimes it’s worth a try to verify an anomaly with a complimentary technology. In this instance, ground microphones, regarded as a conventional a leak detection tool, were deployed to try and detect leak sounds. Although the suspect area was marked, neither Pure nor the client could pick up leak-related sounds from the ground microphone.

Even though the leak was not picked up by the ground microphone, Pure was confident that the acoustic signature from the SmartBall was caused by a leak, based on more than 15 years of experience identifying leaks. That confidence and experience proved right, and when the suspected area was excavated, the leak was located within a meter of where data analyst calculated the leak to be.

The results gave the City of Ottawa actionable data regarding the condition of their pipeline, and the City was able to fix the leak reducing non-revenue water loss and any potentially costly damage caused by the leak. It’s a great example of a proactive utility taking efforts to improve the reliability of its services.

SmartBall extracted by Pure technicians

Oil and gas pipeline owners routinely conduct inspections of their assets by using inline inspection pigs. These tools are used to identify defects within the pipeline and need to be tracked throughout an inspection. Pipeline owners have several options to track a pig such as legacy tracking, remote tracking, and batch tracking, which is sometimes considered as a viable alternative to legacy or remote tracking.

Batch Tracking can be Difficult and Risky

Batch tracking involves measuring pump and flow rates to estimate how far a pig has traveled through a pipeline. The data measured is then compared to pipeline drawings to make an estimate of the pig’s location at a given time.

Depending on the tolerance of the metering system and the bypass rates on an individual pig, locating the tool can be very challenging. Batch tracking also does not provide any dynamic information about a pig. For example, an unexpected speed excursion or stoppage will go unnoticed.

Remote Tracking provides a more Reliable Option

Although traditional or remote tracking is more expensive than batch tracking, its cost is far outweighed by the risk of losing a pig. Lost pigs can result in costly, unplanned shutdowns to locate and retrieve the pig, which would ultimately negate any costs saved by using batch tracking. Technological advancements such as remote tracking provide a cost-effective alternative to batch tracking.

Sensor for tracking

Remote tracking can reduce an asset owner’s risk exposure by providing reliable information during an ILI run. Tracking a pig is the best way to ensure your assets are safe and that you can respond to any incident.

Remote tracking uses a combination of above ground markers (AGMs) and remote tracking units (RTUs) to track a pig during an ILI run. Pig passages are detected using multiple sensors to ensure that the pig is being tracked using more than one indicator. In addition to tracking with multiple sensors, pipeline owners and ILI vendors are provided with a record of each pig passage, making it easier to see when passages are not auditable using a standard geophone.

To learn more about advanced pig tracking, download PureHM’s pig tracking whitepaper.

Download full PDF

*Published in World Pipelines Magazine

The oil and gas pipeline industry has been under close scrutiny for a long time. It leads the way as one of the most regulated industries in the world, and for good reason.  With so many safety-related, social and environmental factors at stake, comprehensive regulation ensures rigorous standards for the design, construction, operation and maintenance of O&G pipeline systems.

Global economics and political activism also play a role in shaping today’s conversation about pipelines. In North America, public debates about the Keystone XL Pipeline have dominated much of the recent news, compelling operators to vigorously participate in the discussion and advocate their integrity management programs. Although Keystone has been put on hold, social capital can assist in getting projects of this magnitude on the radar again.

Through it all, much of the dialogue has focused on the industry’s commitment to protecting communities and the environment from risk by means of rigorous pipeline integrity management programs. As a result, the requirement for increased pipeline safety drives innovative research into improving the sensitivity and reliability of inline inspection (ILI) tools.

Most operators already deploy trusted inline technologies that detect structural deterioration and help maintain pipeline integrity. However, with pressure mounting from stricter regulation, increased operational costs, commodity price-driven budgetary pressure, and often limited available resources, operators face an increasing number of challenges, including vigilance from highly engaged consumer groups.

Although the pressure to perform is greater than ever, operators are responding appropriately with greater confidence in modern technologies to assist in the operation and monitoring of their pipeline systems.

Better ILI tools instill better confidence in containment

To have confidence in the pipeline, operators must have confidence in the capabilities of ILI tools to detect small anomalies that could lead to potential failures.  They must also trust the reliability and interpretation of the data, knowing with as much certainly as possible that the depth, size and location of the pipe wall anomaly is correct.

Overall the news is good. Between 2002 and 2013, Canadian Energy Pipeline Association (CEPA) member companies were able to transport oil and natural gas with a 99.999 percent safety record. While that statistic sounds impressive, headline-grabbing pipeline incidents do occur, (in 2014 there were 122 natural gas and liquid releases) and when that happens, the repercussions can undo years of containment management trust and goodwill.

While the oil and gas industry boasts a remarkable safety record, a reliance on conventional tools limit the near perfect record.  As much as the technologies have been refined, regulators have noted that inline inspections don’t pick up all defects, and expedient follow-through often depends on the people analyzing the data and planning repairs, a process that can take months.

“Despite their sophistication, the detection capabilities of inline inspection tools have limitations,” the US National Transportation Safety Board noted in its report on the 3.3-million-liter 2010 spill in Michigan.

Limitations of conventional ILI inline inspection technologies

The oil and gas pipeline industry has access to an extensive toolbox of technologies for robust integrity programs. Some tools address cracks or corrosion issues, while other tools focus on stress, pressure and product containment. Cost, resolution, reliability, data analysis speed – each technology has its own strengths and limitations, with no silver bullet as the single solution for collecting pipeline condition information.

For example, there is a strongly-held belief in hydrostatic testing as a reliable method to test a pipeline’s integrity. One of the earliest inspection techniques, hydrostatic testing determines if a pipeline can hold its operating pressure. A form of destructive testing, hydrostatic inspection involves purging the product, flooding the line with water, pressurizing it to a predetermined level and maintaining the pressure for a period. Based on the results, detected anomalies in pressure, volume and density can be a precursor to leaks.

Critics however, argue and have quite effectively demonstrated that the hydrostatic tests lack the ability to monitor ongoing corrosion or cracking and that the high pressure environment can exacerbate previously small defects, increasing risk of future rupture.

Smart pigs for detecting large cracks and corrosion

Unlike hydrostatic testing, which is often conducted on pipelines for acceptance testing or for pipelines recently rehabilitated, pigging is the more commonly accepted method of testing pipeline integrity.

While newer “smart” pigs have an excellent reputation for accuracy, their efficacy is often limited to detecting corrosion and cracking that exceeds the threshold for detection of the technology.  Small corrosion pits and cracks, especially cracks grouped in a colony, can pose a challenge to most conventional ILI pigging devices.

The various ILI technologies are sensitive to axial or circumferential defects, and each has limitation for minimum aspect ratios or cross sectional wall loss area before the ILI tool can report the anomaly.  It is also possible to have cracks and wall loss pits that are in close proximity to girth welds, long seams, and other features in the pipe, which can mask the defect, preventing the ILI tool from properly identifying and sizing.  As a result, it is possible to have leaking cracks and corrosion pits that are too small to be sized and reported from conventional ILI.

Not all lines are piggable

Some pipes are more suitable for pigging than others. While most oil and gas transmission lines were built in long straight sections suitable for pig runs, sections with small diameter pipe and small bend radius pipe configurations can limit many ILI tools.  Lines with expansion loops and miter bends, and in the case of natural gas lines, those with reduced port valves, are factors that can prohibit or restrict the traversing of inline tools.

Mass balance measurement and other leak detection tools

To make up for the limitations of conventional ILI technologies, operators often deploy measurement methods and leak detection technologies to complement their integrity programs.

Mass balance is a means of detecting leaks by measuring the mass of product entering the pipeline compared to the mass exiting the pipeline. The limitation for detecting small leaks is the sensitivity of the mass meters being used (2-4% accuracy for conventional orifice meters and 0.25% for turbine meters), and the fact that the product temperature and pressure changes as it moves through the pipeline.

While mass balance is a means to determine leaks, it is also recognized that making actual measurement of mass from volume (through a meter) at different temperature and pressure going in versus coming out of the pipeline, in real time, is difficult, and not very precise or sensitive to small leaks.

As a result, a leak has to release more product than the total tolerance of the mass balance system before a positive leak/release event is alarmed.

Acoustic leak detection

Minute cracks are often preliminary indicators of potential small leaks that produce acoustic emissions at levels often unrecognizable over background noise.

Acoustic leak detection can be conducted with geophones/hydrophones, comparators and acoustic fiber optic techniques, and each of these acoustic tools is subject to different background noise limitations to determine leak detection thresholds.  Not only can these tools have limitations to prevent small leak detection, the expense from installing permanent acoustic systems may reduce the practicality of these technologies.

Emerging technologies on the horizon

To complement hydrostatic testing, conventional pigging tools, and leak detection technologies, the oil and gas industry is evaluating a growing number of emerging external confirmation of containment technologies. These include vapour-sensor systems, hydrocarbon-sensing cables that change in the presence of hydrocarbons, internal pressure wave based tools and fibre-optic based systems that detect temperature changes and acoustic signals associated with leaks.

While these technologies offer hope for more precise surveys, they have yet to be universally accepted or proven. Many are still under development and often require economically impractical installation requirements.

However, there is an innovative, multi-sensor ILI platform that has been used in integrity management programs since 2006, gaining the attention of major pipeline players who have tested the platform, which has now been used on over 25,000 kilometers of pipeline in total.

Introducing SmartBall® technology for Oil & Gas pipelines

To provide a realistic snapshot of a pipe’s condition, many proactive operators are deploying SmartBall technology,  a free-swimming multi-sensor tool for long inspections of piggable and difficult to pig liquid and gas pipelines 4 inches and larger. This advantage makes the ball-shaped tool an excellent choice for traversing not just standard diameter pipes, but for smaller diameter liquid lines and for gas pipelines with loops and frequent sharp bends and heavy wall fittings.

During an inspection, the SmartBall sensors collect acoustic, pressure, temperature, magnetic and inertial data from inside the pipeline.

Primary applications for the SmartBall tool

SmartBall surveys can be conducted independently, at regular intervals, as part of a routine pipeline integrity management program, or as a value-add to inspection programs along with hydro-testing, ILI, or direct assessment.

The tool is launched and retrieved at existing pig traps and is tracked using proprietary acoustic receivers and/or Armadillo pig tracking boxes (AGMs). The location data from acoustic receivers and tracking boxes is used during data analysis to locate any anomalies.

SmartBall technology has three primary applications, and the multi-sensor tool can provide a variety of pipeline data.

1. Confirmation of Containment

Regular confirmation of containment surveys are an important part of integrity management as leaks are often a preliminary indicator of pipe failure.

Unlike conventional leak detection systems, confirmation of containment with SmartBall supplements these systems. The SmartBall tool directly passes leaks, and is therefore capable of detecting losses as small as 150 mL/min, which can be several orders of magnitude more sensitive than conventional methods.

SmartBall surveys can also complement regular ILI surveys by addressing potential pinhole anomalies that have aspect ratios below the reporting threshold of ILI systems.

2. Pressure and Temperature profiles

As the SmartBall is rolling and not sealing against the pipe ID, as conventional pigs do, the tool can also record precise pressure and temperature profiles. The SmartBall platform can be deployed in gas pipelines, where pressure and temperature profiles can be integrated into flow models to assess the points where water vapor may condense out of the gas.

The tool can also be used to assess the point where high temperatures from pump or compressor output may have affected the pipe coating, as well as in settings to validate and improve SCADA and mass balance systems.

3. Pipe Wall Assessment and Inertial Mapping

During inspection, the SmartBall Pipe Wall Assessment (PWA) tool collects magnetic data that can provide a screening of the pipe wall for stress resulting from features like large cracks, large wall loss, dents and points of excessive loading.  The test can also complement hydrostatic testing, as it can survey the pipeline before and after hydro-tests to identify stress that is indicative of pressure reversals.

In addition, the SmartBall PWA tool can produce a girth weld and joint tally for the pipeline, as well as can confirm locations of bends and general geometry of the pipeline.

Helping operators make better decisions

Admittedly, SmartBall is not designed to compete with high resolution technologies like Magnetic Flux Leakage (MFL), which can provide detailed wall loss data.

What SmartBall can do is complement other integrity tools by providing additional data sets to ensure pipeline integrity. In a single deployment, it can detect anomalies associated with pinhole leaks and stress that doesn’t necessarily involve wall loss; e.g. geotechnical strains.  It can also detect change in pressure and temperatures.

Ultimately, the SmartBall tool can help capture enough data to confirm the integrity of the pipe and give operators enough microscopic knowledge to make better, informed, risk-based decisions on the health of their pipelines.

Oil and gas pipeline owners conduct routine inspections of their pipelines using inline inspection (ILI) tools known as pigs. ILI pigs can identify defects within the pipe wall and need to be tracked when they are travelling through a pipeline.

Pig tracking can be expensive (as much as 25% of the ILI budget) and costs can vary from vendor-to-vendor, especially when you factor in the different methods used to track pigs, such as remote tracking and conventional tracking. In order to ensure that tracking budgets are used efficiently and defensibly, each ILI run should be thoughtfully planned to determine the most appropriate tracking method.

Per Mile Cost Fluctuations

Drawing of a worker

Even after thorough planning, cost estimates can vary from vendor-to-vendor, raising questions about per mile cost fluctuations. To reduce the per mile cost of tracking, service providers often reduce the quality of tracking per mile. In traditional tracking, sending out lesser-trained technicians at cheaper rates, enacting only minimum safety measurements and using only one tracking sensor to identify pig passages are all ways that vendors can reduce per mile tracking costs.

An important consideration for pipeline owners and ILI vendors is determining how much risk they are willing to take when tracking their ILI programs. In most cases reducing the per mile costs by 10 to 15 percent is not worth the risk of using low-quality tracking techniques. A single missed or lost pig can easily negate the savings from using the lowest-cost provider.

In most cases, using remote tracking can decrease both the risk and cost of an ILI run. Remote tracking requires fewer staff and equipment resources than conventional tracking and is much safer.

To learn more about remote tracking and its benefits, download PureHM’s pig tracking white paper.

Download full PDF

City of Montreal Skyline

The City of Montreal believes that the best medicine is preventative medicine, especially as it applies to its water network.

Montreal has an impressive water system that supplies drinking water to a population of nearly 1.9 million people. Since 2002, the historic city, the second largest metropolis in Canada, began a long-term major rehabilitation of its extensive network of water main (770 kilometers) and distribution pipes (4,600 kilometers).

In 2015, as part of a pre-emptive program to reduce loss of non-revenue water, the City partnered with Pure Technologies (Pure) to conduct an ongoing, three-year leak detection survey on a series of critical pipes within its network, several of which are located in the downtown core.

Inserting tools through inspection hole in a street

Stopping small leaks from developing into major breaks

The City recognized the value of detecting leaks, however small, to prevent these from developing into greater problems. Compared to a major pipe rupture, which can cause catastrophic damage and incur immediate excavation and costly repairs, small leaks are less obvious at first, and can seep underground for some time without obvious detection.

In addition to physical losses of water caused by a series of small leaks, the escaping non-revenue water can eventually erode the surrounding soil making the area more prone to washouts or sinkholes, a major headache especially in densely populated areas. Unplanned excavations to repair unforeseen leaks can also erode consumer confidence in a public utility.

Leak detection strategy includes Sahara acoustic video inspection

For its multi-year leak detection program, the City requested Pure to deploy its highly reliable and precise Sahara® acoustic video inspection on 46 kilometers of pipelines chiefly in the downtown core. The pipeline sections consist of bar wrappedsteel and cast iron pipe.

The Sahara platform is modular, and can be configured with a variety of sensor tools to perform the condition assessment. This includes an acoustic sensor to perform leak and gas pocket detection, a high-resolution video camera to assess internal pipe conditions, and an electromagnetic sensor to identify stress in the pipe wall.

Because the Sahara tool is drawn by product flow via a small drag chute, and is tethered to a data acquisition unit on the surface, it gives the operator close control to confirm suspected leaks, gas pockets and other pipeline anomalies. The tool can visually confirm pipe irregularities, continuously recording, allowing for both real-time and post-processing analysis.

Workers during Sahara device insertion

 

Data used to shape urgency and timing of rehabilitation efforts

For the Montreal project, the purpose of the Sahara inspection was to assess the condition of the pipeline by identifying and locating leaks, pockets of trapped gas and to identify larger visual anomalies utilizing Closed Circuit Television (CCTV) footage collected during the inspection. The data would help shape the rehabilitation urgency and timing.

To date, a total of 13.2 kilometers have been assessed. Analysis of the data identified eight (8) leaks and zero (0) gas pockets in the pipeline sections inspected. The Sahara sensor was tracked above ground using the Sahara Locator device to pinpoint in real time the location of any potential leaks or anomalies.

The leak detection program has not been without challenges. Valve operations were needed to achieve required pressure flows, and mobilization had to be based on hours of demand, and inspections conducted during those hours.  A number of tight chamber clearances meant the creation of new insertions taps, and because of the urban environment, markings had to be precise, and crews had to deal with traffic issues.

Despite challenges, the assessment is proving its worth from a verification viewpoint, and the leaks have been either repaired or addressed for prioritization. The current program is scheduled for completion by 2017.

With its pre-emptive leak detection program, the City is Montreal is a great example of a smart water manager taking proactive efforts at keeping its network in healthy shape.

The most common form of pipeline integrity used by oil and gas pipeline owners is inline inspection (ILI). Inspection pigs are widely used to clean pipelines, as well as identify areas of damage along the pipe wall to ensure the safe delivery of energy products.

Historically, once a pig is deployed in a pipeline, a technician confirms the tool’s arrival time at various tracking locations throughout the planned inspection distance. Once the tool has passed each location, it is out of sight until it reaches the next tracking point. However, recent technological advancements in tracking technology now allow for pigs to be tracked remotely throughout an entire ILI run.

Remote tracking combines the use of above ground markers (AGMs) and Remote Tracking Units (RTUs) that are deployed before an ILI run is scheduled to take place and are used to track the pig from a central location. When a pig approaches a tracking site, the RTU and AGM are activated to track the tool, which eliminates the need to have a field technician to be on site.

Consistent Live Tracking

PureHM has developed a web-based software called LiveMap that tracks a pig throughout the entire ILI run. LiveMap provides real-time updates via email or SMS with the pig’s location, speed, and estimated time of arrival to ensure that there is better visibility for stakeholders during a project. This advanced technology mitigates the risk of unexpected challenges in an ILI run, such as a stuck pig or speed excursion.

Live tracking offers more control throughout an inspection, and can help prevent costly incidents such as lost pigs by providing accurate information on a pig’s location. A lost pig can interrupt or stop product flow in a pipeline, and can lead to pipeline damage and unforeseen service disruptions.

LiveMap drawing

During an ILI run, the time and speed information collected each time the pig passes the AGM is updated and presented in LiveMap. In traditional legacy tracking runs, this is completed and reported by the field tracker, while in remote tracking runs this is completed automatically with a defensible record of the passage.

To learn more about remote tracking, download PureHM’s pig tracking white paper.

Download full PDF

Kingston Pipe Material Map

Internal measurement map indicates various pipe materials detected during the conditon assessment of the Dalton Avenue force mains in Kingston.

The familiar adage, “never assume anything” certainly applies to the water and wastewater pipeline industry. The message was brought home to Utilities Kingston (UK) early this year when the utility was surprised to find unexpected pipe material on sections of pipe during a condition assessment on its Dalton Avenue (North End) Pump Station force mains.

Conducting a condition assessment on a pipeline can pose a particular challenge if the pipe material is unknown, as each pipe type exhibits specific characteristics that affect its structural integrity. Despite the challenge, UK managed to move forward thanks to assistance from Pure Technologies, bringing its inspection, risk assessment and engineering analysis services, along with its comprehensive suite of technologies to survey the pipeline for leaks, gas pockets and wire breaks.

Utilities Kingston is unique in Ontario, combining water, wastewater, gas and electrical services, and a broadband fibre optics provider under one company.  UK’s engineering and public works departments provide potable water and wastewater collection and treatment to 36,000 customers.  The utility owns and operates approximately 550 kilometres of water mains and 500 kilometres of sewer mains to service the local population of nearly 125,000.

With an average age of 35 years, each of their pipeline assets is entering a critical stage in its life-cycle.

The subject pipeline had experienced a failure and as a result, the utility was interested in exploring technologies to help them implement a comprehensive asset management program for their pipelines.

Condition assessment includes various screening technologies

UK retained Pure to perform a condition assessment inspection, consisting of a SmartBall® leak detection survey, a PipeDiver® electromagnetic inspection and a transient pressure monitoring on the Dalton Avenue Sewage Pump 450-millimeter and 600-millimeter force mains. The two sewage force mains are both approximately 1,550 meters long and follow a parallel route for approximately 1 kilometer.

The older of the two force mains is 450-mm (18-inch) in diameter, constructed of ductile iron, was built in the late 1950s, and had failed several times over its lifetime. The newer of the two force mains is 600-mm (24-inch) in diameter was an unspecified concrete pipe from the early 1960s. As the pipe material specifics were still unknown at the time of the inspection, Pure elected to conduct a free-swimming PipeDiver electromagnetic run to accommodate both possible types of pipe material – assumed by all to be bar wrapped pipe (BWP) and prestressed concrete cylinder pipe (PCCP). The PipeDiver inspection platform uses electromagnetic (EM) sensors to evaluate the existing condition of the pre-stressing wires. EM inspections collect a magnetic signature for each pipe section to identify anomalies that indicate zones of wire break damage. The presence of wire breaks in concrete pressure pipe is often a sign of impending failure.

Pure’s SmartBall tool was deployed on both pipes, checking for leaks and gas pockets.

PipeDiver on a street

Force main defects can vary from one pipe material to another

During a forensics exercise on the 600-mm force main using 12-detector PipeDiver technology, it was revealed that rather than BWP or PCCP, the actual pipe material included reinforced concrete pipe (RCP), which is not usually used in pressurized environments. Electromagnetic inspection of the RCP can only reveal anomalies on the circumferential cage and not the longitudinal bars.

Furthermore, the inspection identified 102 suspected metallic pipes, which were not identified as such in the original plan and profile drawings.

PipeDiver tool before insertion

Prepping the PipeDiver tool before insertion.

Pure first: metallic pipe condition assessment using mini PipeDiver tool in wastewater

Pure deployed its electromagnetic 24-detector mini PipeDiver tool to conduct a condition assessment of the 450-mm pipe. The purpose of the enhanced electromagnetic inspection is to locate and identify steel and ductile iron pipes that have indications of wall loss.

This marked the first condition assessment of metallic pipe using the 24-detector mini PipeDiver tool in wastewater, an exercise that confirmed the validity of the tool’s sensor technology.

Results lead to actionable information regarding rehabilitation

In the end, one (1) acoustic anomaly characteristic of transient gas on the 450-mm forcemain was identified during the analysis of the data collected during the SmartBall tool inspections.

No anomalies resembling leaks were identified within the 600-mm force main.

Of the 650 pipes inspected, a total of 55 pipes in the 450-mm Dalton Avenue Pump Station force main had electromagnetic anomalies characteristic of localized wall loss (DIP). These results represent a high percentage of distress along the length of the pipeline and indicate a high risk of failure.

The data collected from both the inspections and transit pressure monitoring gave Utilities Kingston a better understanding of their real, not assumed assets. The results were used to complete a structural evaluation of the force mains, and have provided UK with actionable information regarding any necessary repairs or rehabilitation.

Team Members of Pure and UK

Members of the Pure and UK team pose after a long day of inspection.

In order to mitigate risk, pipeline owners spend approximately $1.5 billion every year on pipeline integrity for the thousands of kilometers of pipe across North America. Pipeline integrity often employs the use of inline inspection (ILI) tools known as pigs. These pigs are inserted into a pipeline and pushed along the pipeline by the flow of product. ILI tools have multiple functions, and can be used to clean and assess the condition of the pipeline, as well as to purge different products in a multiproduct pipeline. There is a risk of the deployed pig getting stuck or lost if it is not tracked properly. Locating a lost pig can be costly to the vendors if it is not found quickly and can cause severe damage to the pipeline.

Many legacy tracking providers do not provide a record of each pig passage to prove a pig has actually passed a location. Instead, this is left to the word of the tracker and sometimes is not a reliable source of information. Trackers are not intentionally misleading stakeholders about where a pig is, but traditional methods often make it difficult to tell if a pig has passed or not.

Traditional legacy tracking providers typically use standard geophones to track and identify a pig passage. It is often difficult to determine if a pig has passed because the signal on the geophone is quick and sometimes difficult to hear. This leads to false positives showing a pig has passed even when it hasn’t.

Using more than one sensor to reduce incidents

Using Advanced Pig Tracking, pig passages are detected using multiple sensors to ensure information is defensible and reliable. Advanced tracking systems are equipped with multiple channels. These sensors work simultaneously and reduce incidents of false positives or missed pigs. Not only do these systems come equipped with multiple sensors, but they also provide stakeholders with a record of each pig passage throughout the run.

Sensor for tracking pigs

The record shows the signal of the pig passage as well as the timestamp and pig speed at the specific location. These snapshots can then be uploaded into LiveMap, and are used for real time tracking of the pig’s position, speed, and estimated time of arrival. Conventional above ground markers (AGMs) rely on triggered passage files unlike Advanced Pig Tracking AGMs, which constantly record data when turned on.

To find out more about the other myths of pig tracking, and how Advanced Pig Tracking is more reliable than traditional methods, click the link below.

Download full PDF

Over the past decade, the world has been gripped by many stories of pipeline failures, especially those with severe consequences to the environment and human life. These failures have resulted in billions of dollars in remediation costs, and understandably, this makes pipelines some of the most regulated assets in the world. The use of inline inspection (ILI) tools, such as pigs, is the most common form of pipeline integrity. Pipeline pigs are tools inserted into a pipeline and pushed along by the flow of product through the pipeline. The tool has multiple functions, and can be used to clean and inspect the pipeline, as well as to purge different products in a multiproduct pipeline. When these tools are operating in a live pipeline, it is important to know their precise location and speed, as they are very expensive to replace. A lost or stuck pig can obstruct product flow, causing unwanted service disruptions, or at worst, pipeline ruptures.
Geophone

When tracking a pig through an oil or gas pipeline, it is often difficult to know if it has passed a tracking location, especially for inexperienced pig trackers. The majority of legacy tracking is done only with a standard geophone, a device which converts ground movement into voltage, and relies solely on the word of the technician tracking the pig. By using only a standard geophone, a technician cannot reassure an ILI vendor when the pig has passed a location. The geophone can give a technician many false positives; therefore, the technician’s word will not inspire much confidence in an ILI vendor.

Lack of experience can lead to tracking challenges

To be able to identify a pig passage with only the use of a standard geophone, an experienced tracker needs to reduce the likelihood of error. Many of the trackers who are sent out in the field are inexperienced and are unable to provide this. By solely relying on a standard geophone, field technicians can easily miss a pig passing through a station, and can lead to problems later in the run. Accurate pig tracking requires the right tools and defensible data. Remote tracking can be a more efficient system and provides more concrete data than legacy tracking systems.

Reliable tools and data

The Armadillo Tracks system uses multiple sensors to track every pig deployed into a pipeline. The sensors work simultaneously and record a snapshot of each pig passage. These snapshots prove when a pig has passed a tracking location and helps ILI vendors with benchmarking and reporting. With more reliable tools and data, vendors can have peace of mind knowing problems during a pig run will be minimized.

Technical map generated by Pure & Armadillo Tracks

To learn more about how remote tracking systems benefit ILI vendors and the other myths of pig tracking, download the White Paper here.

Download full PDF

City of Saskatoon

While pipeline management may seem unaffordable, understanding the condition and targeting repair provides an alternate approach to wholesale replacement and allows operators to accomplish the same de-risking effort with less money.

The City of Saskatoon operates more than 100 kilometers of water mains (400 mm diameter and larger) within the Water and Sewer Preservation Group.  The City has an extensive water main break database dating back to 1959, which assigns a condition rating to water main segments. These ratings are useful for evaluating small diameter local lines where the consequence of water outages are low, and a “run to failure” strategy is acceptable.

For large diameter transmission water mains, waiting for failures to occur before repairing or replacing highly critical mains is not an option. A proactive approach to condition assessment is needed.

“The benefits of accurate condition data can be significant,” says Stephen Wood, P. Eng. Water and Sewer Preservation Manager for the City.  “Allocating limited maintenance and replacement funds on the correct locations is crucial and this is impossible without good condition data. However, obtaining condition data on highly critical, non-redundant, pressurized water mains can also be costly. For this reason the City set out to determine where to focus its condition assessment efforts.”

First priority: where to start?

To help Saskatoon better understand its network and overcome its particular challenges, the City partnered with Pure Technologies to help answer the questions: where do we start in prioritizing our pipelines based on Risk, and what strategy should we implement moving forward?

Straight capital replacement is unaffordable. The City recognized the need to set up a risk framework in order to evaluate its highest priority pipelines first, rather than looking at a pipe based on when it was installed.

Pure proposed a data driven, risk-prioritized approach to managing the critical buried infrastructure. The City and Pure worked closely to develop a systematic approach with specific tasks to implement a pipeline risk prioritization plan.

1. Collect existing data and provide a “gap analysis”

Prior to the project, existing information was collected and reviewed as it related to the pipeline assets. Pure looked at maintenance records and compared existing information with what is necessary to develop the preliminary risk assessment and ultimately the condition assessment of each asset. This “gap analysis” provided a summary of the available information related to the pipelines as well as what is not currently available.

At the same time, additional pipeline attributes were gathered, including existing information on material, diameter, failure history, previous rehabilitation, hydraulics, soil sampling, etc.

Risk graphic and aerial map of water main conditions

(Left) Circle size represents the total pipe length under each risk category.
(Right) Aerial map of water main conditions by neighbourhood.

2. Define risk category and establish relevant risk factors

Pure adopted a logical approach to quantify risk as the product of likelihood of failure (LoF) index and consequence of failure (CoF) index. Relevant risk factors were selected after learning the historical pipeline behavior and data availability. Each factor was assessed by a score value between high (5) to low (1).

3. Compute the risk analysis

Based on the metrics of consequence of failure, likelihood of failure scoring and layered with risk mitigation factors, Pure performed a risk computation using PureNet in-house software to determine the highest risk pipes and recommend the inspection technology.

4. Calculate pipeline and neighbourhood risk

Pure had the ability to look at a single line and plot it into risk zones node to node, feature to feature, and within set neighbourhood parameters. The risk zones recognize that pipelines do not deteriorate on a uniform basis. By aggregating the data by neighbourhood, the risk prioritization can help decision makers plan and target regions, facilitate scheduling, maintenance and repairs, and better communicate with stakeholders.

5. Model budgetary needs for different management scenarios

Through the exercise, Pure gave the City a static risk picture to provide a baseline look at the system, as well as a plan to forecast risk and establish appropriate budgets for multiple management strategies.

Pure developed a 50-year pipe replacement plan that systematically replaces pipe based on risk priority up to the available budget in a given year.

“Allocating limited maintenance and replacement funds on the correct locations is crucial and this is impossible without good condition data.”

Replacement model versus condition assessment model

The replacement model offers limited coverage due to the high replacement costs from replacing entire pipe segments at a time. In comparison, the condition assessment model can achieve greater coverage for lower cost due to its unique methodology.

The condition assessment strategy is an approach where a program is developed that systematically inspects pipe based on risk priority and only addresses damage where needed. Under this program, pipelines are screened for repair or replacement depending on current condition of individual pipes. The provision of additional knowledge allows only the worst of the pipes to be addressed and avoids the premature repair or replacement of those pipes still in good condition.

What’s next?

“The results of the report give us a clear indication of the benefits of condition assessment along with a priority list for addressing our highest risk locations,” says Stephen Wood.  “The next step is to put the plan into action. We are currently working on developing a project for 2016 that will provide a condition assessment of approximately 2.5 kilometers of our highest risk water mains.”

In August 2011, Pure Technologies brought out the redesigned PureRobotics wastewater crawler unit to conduct an electromagnetic inspection on a 42-inch (1050mm) sewer force main for a major utility in Ontario, Canada. Pure was able to inspect 3,400 feet from a single access in both directions of the line. New improvements to the tracks assisted in pushing the crawler through the heavy debris at the bottom of the pipe that would otherwise entrap other robotic inspection systems.

Critical large-diameter water transmission mains frequently run beneath city streets in busy urban environments. Like the majority of water infrastructure across North America, these pipes are reaching the end of their design life. However, pipelines in urban environments pose a significantly greater risk and challenge to water utilities.

These pipelines are high-risk because of their high consequence of failure; if a pipe beneath a busy downtown street fails, the repair costs can quickly escalate and the failure causes a massive disruption to businesses and commuters. In some cases, failures in urban environments have cost utilities upwards of $5 million to remediate. A failure not only carries a high repair bill, but contributes to a negative public perception of the utility which can harm consumer confidence and lead to negative public relations.

With such high risk, utilities often prioritize these mains ahead of those with lower consequence of failure. However, because these mains are located in high-traffic areas, assessing them is far more challenging than assessing a linear main in a rural area.

Dealing with above ground obstructions, commuter delays and a lack of access points means that operators need to have close control over inspection technologies. In addition, the technology must provide the best possible information to allow for accurate repair and excavation decisions.

Like other major metropolitan areas, the City of Montréal has aging pipeline infrastructure that runs through its downtown core. In Montréal – one of the oldest cities in North America – this infrastructure is very old and beginning to reach the end of its design life. In order to proactively identify problem areas in its Prestressed Concrete Cylinder Pipe (PCCP) assets, the City is in the midst of an inspection program using advanced non-destructive technologies. In total, the City will assess the condition of over 40 kilometers of PCCP by 2015.

In the majority of cases, assessing the condition of assets to identify problem areas has high value for utilities, since the majority of pipelines have remaining useful life, despite their age. This allows for selective rehabilitation in favour of full-scale replacement. This is particularly important in urban areas, since excavation costs are higher and more disruptive in urban environments.

PureRobotics platform

The PureRobotics platform remains tethered to the surface during inspection. 

Pipe with damaged areas

Verification showed large areas of damage to both the prestressing wires and steel cylinder.

Related Topics

For a large portion of the condition assessment, the City is using the PureRobotics™ platform, since it is ideal for challenging urban environments. The tool remains tethered to the surface during inspection and is controlled by an operator. It also features live high definition video to observe internal pipe conditions. These features allow the City to see internal pipe conditions and closely verify areas with potential problems.

In addition, the tool identifies broken prestressing wire wraps in PCCP. As PCCP ages, the prestressing wires, which make up the main structural component, begin to break due to a number of factors.

The presence of broken wires in PCCP is the main indication that the pipe will eventually fail. Unlike metallic pipe materials that typically fail after a long period of leakage, PCCP is prone to sudden failures when too many wires break in one area. The diagram below demonstrates how PCCP typically fails.

How PCCP Fails

Recently, the City has completed the assessment of just over 17 kilometers of its urban PCCP assets with diameters of 600, 750 and 900 millimeters (24, 30 and 36 inches). Of the 2,798 pipe sections assessed in this 17 kilometers, only 97, or 3.5 percent, have shown evidence of distress. This is slightly below the industry average of 5 percent of pipe sections with distress.

Using condition assessment, the City has been able to identify isolated distress on its critical urban mains, while leaving pipeline assets with remaining useful life in operation.

After completing the initial phases of condition assessment, the City has excavated certain sections of pipe for validation of the inspection results, as well as repair of any damage.

Both the excavation locations and presence of distress have been very accurate. This has allowed the City to repair isolated pipe sections, which restores the overall condition of the pipeline. This will help to prevent failures that would significantly disrupt day-to-day life in the city.
In addition, the City now has a baseline condition of all of the assessed pipelines, which helps in the development of future capital planning for monitoring or re-inspection.

By proactively assessing its PCCP mains, the City of Montréal is taking steps to prevent pipe failures, while allowing for more fiscally responsible asset management in the future.

 

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PureRobotics™ – Pipeline Inspection

Robotic Pipeline Inspection

PureRobotics uses powerful modular robotic pipeline inspection systems that can be configured to inspect virtually any pipe application 12-inches (30.5 centimeters) and larger.

Assess & Address Pipeline Management Program

Assess & Address Pipeline Management Program

Pure Technologies is helping utilities manage their buried infrastructure through its Assess & Address which can often be implemented for only a fraction of the capital replacement cost.

Technical Paper

Beyond the Wires: A Sustainable Approach to Prestressed Concrete Cylinder Pipe Management

While evaluating wire breaks are an important part of PCCP management, it is important to acknowledge additional factors beyond wire breaks. By acknowledging additional condition factors, limitations of wire break assessment, and considering other rehabilitation approaches, there may be a more sustainable PCCP management approach (or combination of approaches).

For water service providers, providing customers with consistent, reliable access to clean water is crucial. In densely populated urban areas, such as the Greater Toronto Area (GTA), this often requires operators to manage and assess pipelines that cannot be removed from service, yet provide water to a large number of end-users.

In April 2013, The Regional Municipality of York, in conjunction with the Regional Municipality of Peel and the Ontario Clean Water Authority (OCWA), assessed the condition of the York-Peel Feeder Main, which stretches roughly 25 kilometers, (18 km in York Region and 7 km in Peel) through both Regions. The pipeline is made of 1800-mm (72-inch) Prestressed Concrete Cylinder Pipe (PCCP) and provides a crucial supply of water to residents and businesses in York Region.

In spring 2014, York Region repaired three leaks found through a prescreening survey and verified the condition of one pipe section showing signs of structural deterioration identified through electromagnetic (EM) inspection.
Identifying leaks in large-diameter transmission mains is important in reducing Non-Revenue Water (NRW) – which can be defined as water that is produced for consumption and lost before it reaches the customer. Reducing NRW helps eliminate waste and contributes to the conservation of a crucial natural resource.

In addition to the environmental benefit of reducing water loss, eliminating leaks plays an important role in pipe integrity. The presence of leaks often indicates a potential failure location and by identifying leaks, utilities can reduce pipe failures and gain a better understanding of the overall condition of their system.

For its prescreening survey, York Region used SmartBall® technology, which is a free-flowing tool that identifies the sound of leaks as it travels through a live, operational pipeline. In total, the prescreening survey identified seven anomalies that resembling leaks. Four of these leaks were matched up with existing pipeline features while the other three were verified and repaired by York Region. One of these leaks was located on a 1200mm, high-pressure line running adjacent to the 1800mm line.

While prescreening and leak detection is an important part of condition assessment, critical large-diameter transmission mains warrant a more detailed inspection to identify areas of structural deterioration. By doing this, utilities can identify specific pipe sections that are at risk of failure before they rupture.

Although inspection shows that a large percentage of pipe sections have no deterioration at all, eliminating the risk of one failure can be very beneficial, since the typical cost associated with a large-diameter pipe rupture is between US$500,000 and US$1.5 million, not including the reputational damage a failure can cause.

To identify distress in its PCCP transmission main, York Region completed a non-destructive EM inspection using PipeDiver® technology. PCCP is a concrete pipe that remains under compression because of the prestressing wires, with the thin-gauge steel cylinder acting as a water membrane. As the prestressing wires in PCCP begin to break, the pipe becomes weaker and is more likely to fail catastrophically. It is important to locate and quantify the amount of broken wires in PCCP as they are the main structural component.

When assessing PCCP, PipeDiver technology locates and quantifies the number of broken wires. This method is extremely effective in identifying pipe sections that should be target for renewal once the number of wire breaks passes a certain limit.

The inspection covered 4,280 pipe sections and identified 17 pipe sections that had signals indicative of wire break damage. This represents less than one per cent of the feedermain, meaning the asset is in very good condition. York Region accurately verified the condition of one section of pipe with an unacceptable amount of wire breaks.

A portion of the project also used the condition assessment data to complete detailed risk analysis that will provide York Region with a better understanding of how their pipes perform. This allows for the development of a baseline condition of the entire transmission main and aids the development of long term management, renewal and re-inspection plans.

Although this pipeline was constructed in 2005 and is relatively young, the condition assessment was completed proactively to ensure the continued safe operation of the asset. Managing risk through proactive condition assessment is an excellent tool for operators of large-diameter pipelines. The York-Peel Feedermain conveys roughly 165 million liters per day and in time, will achieve a maximum capacity of 380 million liters per day.

 

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Assess & Address Pipeline Management Program

Assess & Address Pipeline Management Program

Pure Technologies is helping utilities manage their buried infrastructure through its Assess & Address which can often be implemented for only a fraction of the capital replacement cost.

Free-Swimming Pipeline Inspection

PipeDiver® – Free-Swimming Pipeline Inspection

Specifically designed for structural assessment of Prestressed Concrete Cylinder Pipe (PCCP) lines that are live or can’t be taken out of service due to a lack of redundancy or operational constraints.

For decades, the best way to manage aging pipeline assets was using instinct, which was a precarious method at best. However, with the development of new methods for managing critical water assets, operators are more equipped than ever to manage risk in a way that allows for scientifically defensible and cost-effective decisions.

In March/April edition of Water Canada Magazine, the Regional Municipality of Peel will be featured for its risk management approach to managing its existing and new infrastructure. The article outlines the project’s objectives and how Peel Region is attempting to manage risk with its new water assets.

Read Full Article in Water Canada Magazine »

The Peel water supply system has a total of 4,500 water mains that cover 700 kilometers. The pipe diameters in the system range from 300 to 2,100 millimeters with seven pressure zones.

Meanwhile, Peel’s population is expected to grow from its current 1.3 million to approximately 2.5 million in the next two decades. The region needs to fund new infrastructure while also maintaining the existing aging pipes, all within the constraints of a rate-based water supply system that is supplemented with new development charges.

One approach the region is taking to accommodate a growing population is constructing new transmission mains. The Hanlon Water Project will construct a new 2400-millimeter (96-inch) Prestressed Concrete Cylinder Pipe (PCCP) transmission main. The water main construction project is the largest in Peel’s history and will run approximately 14.5 kilometers from the Lakeview Water Treatment Plant on Lake Ontario to the Hanlan Reservoir and Pumping Station at Tomken Road and Britannia Road East.

With the construction of a new PCCP pipeline, Peel Region is taking the opportunity to make its infrastructure smarter using advanced monitoring technology. In total, 14.5 kilometers (9 miles) of new pipe will be equipped with SoundPrint® Acoustic Fiber Optic technology, which monitors the condition of PCCP in real-time.

The monitoring system is able to record the acoustic signature of prestressing wire breaks in the pipe. In PCCP, the high-strength steel prestressing wire wraps are the main structural component – as these wires begin the break, specific pipe sections become weaker and more likely to fail. Each time a wire wrap breaks, Peel Region will receive a notification with the location of the wire break, allowing them to track how many wire breaks have occurred on each pipe section. This will allow the region to intervene once a pipe section has an undesirable number of wire breaks and is at risk of failure.

However, beyond preventing potential pipe failures, the monitoring system will also allow the asset to be monitored for its entire service life, which is rare for most pipelines, which typically begin to get monitored at some point during their service life. In theory, with regular maintenance, the monitored PCCP mains could have an indefinite service life, since deterioration will be tracked and mitigated on an ongoing basis.

 

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Assess & Address Pipeline Management Program

Pipeline Monitoring

Providing real-time critical data of a prestressed pipeline allows the asset owner to effectively monitor changes in structural integrity and address necessary improvements.

TRA Verification
To supply roughly 500,000 people from eight different municipalities with treated water, the Lake Huron Primary Water Supply System (LHPWSS) operates a major 1200-mm (48-inch) Prestressed Concrete Cylinder Pipe (PCCP) transmission main that spans 47 kilometers (29 miles).

After four failures on ‘Pipeline A’ in 2012, 2010, 1988 and 1983, LHPWSS began taking a proactive approach in managing its most critical pipeline through a technology-driven management program. This includes regular inspection of the transmission main to identify specific pipe sections that have distress and are at risk of failure.
In addition to proactively managing its infrastructure, LHPWSS is also twinning the transmission main to provide redundancy in the event that Pipeline A needs to be shut down.

After a full inspection of Pipeline A in November 2012, LHPWSS assessed 6.5 kilometers (4 miles) of PCCP along the twinned ‘Pipeline B’ in December 2013 using the PipeDiver® platform. Pipeline B currently spans 28.5 kilometers (17.7 miles) and features both PCCP and Steel pipe.

The PipeDiver tool is an electromagnetic (EM) platform that operates while a pipeline remains in service. EM inspections of PCCP pipelines identify the quantity and location of broken wire wraps, which are the main structural component in PCCP. As these wraps begin to deteriorate and break, the pipe section becomes weaker and more likely to fail catastrophically.

Worker inside a pipe
Staff extracting the PipeDiver® tool

Pure’s staff extract the PipeDiver® tool from LHPWSS’s Pipeline B.

LHPWSS’s inspection of Pipeline B was also the first use of video on the PipeDiver platform. Through the video application, LHPWSS was able to see inside the pipe under live operating conditions. The use of video during inspection provides additional information to use in conjunction with the electromagnetic data.

While the full results of the Pipeline B inspection are not finalized, the inspection demonstrates LHPWSS’s commitment to preventing transmission main failures and providing reliable water service.

This approach has been effective for LHPWSS in the past, as the 2012 inspection of Pipeline A identified only 58 pipe sections with EM anomalies out of a possible 10,000 pipe sections. This represents a distress rate of only 0.6 percent – well below industry average. Of the identified anomalies, only seven pipe sections had a relatively high level of distress.

Of the pipes with relatively high distress, two were located within a twinned section and therefore had a lower consequence of failure. The remaining five pipes were located within 3.5 kilometers (2 miles) of each other and are in the same vicinity of failures that occurred in 2010 and 2012.

LHPWSS has since verified and replaced the three most distressed pipes from the five that didn’t have redundancy to mitigate the risk of another failure. Plans to replace the remaining two pipes are scheduled for 2014.

By identifying isolated problems on its major transmission main, LHPWSS is able to avoid completing expensive and challenging replacement projects while maintaining safe pipeline operation. This approach allows capital to be deferred to other projects and prevents the replacement of pipe sections with remaining useful life.

 

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Case Study

Case Study: Lake Huron Primary Water Supply System

In October 2013, LHPWSS and Pure Technologies used advanced non-destructive free-flowing technologies to inspect a critical transmission main for leaks, gas pockets and structural deterioration while the pipeline remained in service. The results were successfully validated in spring 2013.

Assess & Address Pipeline Management Program

Assess & Address Pipeline Management Program

Pure Technologies is helping utilities manage their buried infrastructure through its Assess & Address which can often be implemented for only a fraction of the capital replacement cost.

Around six billion gallons of treated water is lost every day in the United States – this represents about 16 percent of the country’s daily water use. While this represents the loss of a critical resource, it also represents a significant financial burden for end users, since the lost revenue from aging pipes, faulty meters and illegal connections often leads to higher rates – between 1996 and 2010, the cost of water services in the US rose by nearly 90 percent.

In the Great Lakes states (Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin), specifically, roughly 66.5 billion gallons of treated water is lost every year. This is enough water to meet the annual water needs of roughly 1.9 million Americans.

In an effort to establish the Great Lakes states as leaders in sustainable water management and develop best practices, the Center for Neighborhood Technology (CNT), a Chicago-based nonprofit focused on sustainable cities, released a report titled The Case for Fixing the Leaks, which is part of a collaborative campaign focused on Great Lakes states, calling for leadership in improved water management.

The report focuses on region-specific challenges to water loss and outlines potential solutions to help utilities manage their water infrastructure in the long term.

Read The case for Fixing the Leaks” Report»

AFO Monitoring
Leaking Pipe

Leaking pipes contribute to the loss of 16 percent of treated water in the United States.

Sahara Insertion

Pure Technologies staff insert the Sahara® tool into a live pipeline.

Leaks Map - CNW

One method that utilities can use to reduce their Non-Revenue Water (NRW) – which can be defined as water that is produced for consumption and lost before it reaches the customer – is having a well-developed leak detection program for both small- and large-diameter water mains.

For large-diameter pipes, the most effective method of identifying leaks is through the use of inline leak detection. This method brings the leak detection sensor directly to the source of the leak, which provides the highest level of accuracy. Non-invasive methods, such as correlators or listening sticks, work very well on small-diameter distribution mains but often lack the accuracy needed to address large pipes as the sound of a leak does not travel as well as pipe diameter increases.

According to one study by the American Water Works Association (AWWA), accurately locating and repairing leaks on large-diameter mains is the best way to reduce NRW through leak detection, as almost 50 percent of the water lost through leaks is through large-diameter pipeline assets. Identifying leaks also increases service reliability and reduces the likelihood of a pipeline failure, as the presence of leaks is often a preliminary indication of a failure location.

To accurately locate leaks, Pure Technologies offers two different solutions that can typically locate leaks within 6-feet (1.8-meters) of their actual location.

The SmartBall® platform is a free-flowing acoustic tool that can survey long distances in a single deployment while a main remains in operation. The Sahara® platform is a tethered tool that provides close control of the acoustic sensor as well as real-time leak detection. Because the tool is tethered to the surface, the operator can closely locate and confirm suspected leaks by winching the sensor back and forth.

Both technologies locate leaks using an acoustic sensor that identifies the unique sound of water leaking from the pipeline and are effective on any pipe material.

With over 2,000 miles of large-diameter pipelines inspected, Pure Technologies has located more than 4,000 leaks for an average of 2.2 leaks per mile using advanced inline leak detection technologies. Locating these large-diameter leaks has significantly reduced NRW, saved millions of gallons of water and helped prevent failures for utilities across North America.

 

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Pipeline leak detection systems

Pipeline Leak Detection Systems

Highly accurate inline leak detection systems that can detect leaks and gas pockets in operational pipelines. These systems are used primarily on larger diameter water and wastewater transmission mains of all materials as well as oil & gas pipelines.

Non-Revenue Water (NRW)

Non-Revenue Water (NRW)

Each day, billions of gallons of water are lost worldwide. Not only does this represent the loss of a precious resource that not everyone has access to; it represents a massive amount of lost revenue for the utilities that provide it.

In the October 2013 issue of Trenchless Technology, the Lake Huron Primary Water Supply System (LHPWSS) was recognized for its proactive pipeline management program.

LHPWSS serves about 500,000 people in eight different municipalities in the London Region and provides about 44 million gallons of water per day (170 million liters). Its major transmission main, the Lake Huron Pipeline A, runs from the Lake Huron Water Treatment Plant near Grand Bend, ON to a terminal reservoir located near the community of Arva, North West of the City of London and features mostly 1200-millimeter (48-inch) Prestressed Concrete Cylinder Pipe (PCCP).

In October 2012, LHPWSS and Pure Technologies completed a 47-km condition assessment of Lake Huron Pipeline A using advanced non-destructive technologies. The system has about 25 km of non-redundant pipeline, making it very difficult to shut down for inspection and repairs without disrupting water supply to customers.

The proactive condition assessment allowed LHPWSS to selectively rehabilitate its most critical pipeline in favor of replacement.

All of the winners are featured in the October 2013 issue of Trenchless Technology magazine and will be formally recognized at the 2014 No-Dig Show, to be held in Orlando, Florida. Winners are chosen on the basis of technical advancement, technical complexity, milestones and records achieved, interaction and cooperation, and advancement of the trenchless industry.

Read Full Article»

 

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PipeDiver Device Extraction
Staff verifying EM results

Pure’s staff successfully verify the EM results on behalf of LHPWSS in spring 2013.

Case Study

Case Study: Lake Huron Primary Water Supply System

In October 2013, LHPWSS and Pure Technologies used advanced non-destructive free-flowing technologies to inspect a critical transmission main for leaks, gas pockets and structural deterioration while the pipeline remained in service. The results were successfully validated in spring 2013.

Assess & Address Pipeline Management Program

Assess & Address Pipeline Management Program

Pure Technologies is helping utilities manage their buried infrastructure through its Assess & Address which can often be implemented for only a fraction of the capital replacement cost.

Inspection methods for BWP and steel pipe that locate cylinder corrosion have only recently been developed and commercialized. Specifically for BWP inspection, tools that can identify both bar breaks – which are an indication of corrosion – and corrosion on the steel cylinder are the best for completing a thorough condition assessment.

The City of Calgary provides water and wastewater services for over 1 million people in the Greater Calgary area; many of its large-diameter transmission and sewer force mains are made of PCCP and BWP.

In an annual proactive condition assessment program, the City of Calgary inspects its PCCP and BWP for signs of deterioration using electromagnetic (EM) technology.

In May 2013, the City inspected 1.6 miles (2.2 km) of the 30-inch (750-mm) BWP Memorial Feedermain using PureRobotics™, which is a powerful robotic system equipped with PureEM™ technology that can be configured to inspect a variety of pipelines and materials with different operational conditions. In BWP, it is capable of locating both bar breaks and cylinder corrosion.

In August 2013, the City verified the results with Pure Technologies by excavating a pipe section that was identified as distressed during data analysis.

The results from the inspection identified only 3 of 232 BWP pipe sections with evidence of bar breaks, as well as 3 additional pipe sections with evidence of cylinder anomalies.

Pure Technologies’ data from over 8,000 miles of pressure pipe condition assessment indicates that only a small percentage of pipes (less than 5 percent) are in need of repair and therefore have a significant remaining useful life. Condition assessment data also suggests that pipe distress is localized and a significant ROI can be achieved by locating and addressing isolated problems through structural inspection.

In August 2013, the most distressed pipe section was excavated for verification. The results had predicted bar breaks and cylinder corrosion, which can eventually lead to pipe failure if not repaired or replaced. The validation confirmed the broken bars and a large area of cylinder corrosion.

Staff verify the pipe condition

Pure Technologies staff verify the pipe condition

Pipe verification

Verification of one pipe revealed bar breaks and corrosion.

The City of Calgary was pleased with the results, and through condition assessment, has been able to identify and address individual distressed pipe sections on an otherwise serviceable transmission main. This has allowed the City to avoid a potential rupture of the main in a high consequence area while increasing service reliability and the useful life of the Memorial Feedermain.

The other sections identified in the inspection have been prioritized and will be verified in a future repair cycle.

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Case Study

Case Study: City of Calgary Memorial Feedermain

In August 2013, the City of Calgary and Pure Technologies verified bar breaks and cylinder corrosion on a 30-inch Bar-Wrapped Pipe section on the Memorial Feedermain. The distressed pipe was identified in an annual inspection completed in May 2013.

Pipeline Inspection and Condition Assessment Services

Pipeline Inspection and Condition Assessment Services

We provide water and wastewater organizations a comprehensive suite of technologies that provide actionable pipeline information to better understand the condition of their pipe.

Technical Paper

Failure Risk of Bar-Wrapped Pipe with Broken Bars and Corroded Cylinder

This study investigates the behavior of a deteriorating BWP under various levels of distress and various internal pressures. The results based on a 24-inch pipe transmission main, are used to define criteria to evaluate the performance of a damaged BWP. Based upon the finite element results obtained in this study, suggestions for future work are presented and discussed.

Roughly US$14 billion in clean, non-revenue water is lost every year due to leaks and water main failures that could have been prevented.

If the loss of non-revenue water could be cut by half, an estimated US$2.9 billion could be generated and an additional 90 million people could have access to water.

Locating leaks on transmission mains represents the best opportunity for improvement.

Non-revenue water is defined as water that is produced for consumption but is lost before it reaches the customer. These losses are divided into three categories:

  • Physical (or real) losses due to poor operation and maintenance, lack of an active leak control system or the poor quality of underground assets.
  • Commercial (or apparent losses) include customer meter under-registration, data handling error or the theft of water in various forms such as illegal connections.
  • Unbilled authorized consumption includes water used for operational purposes, for fighting fires and water that is provided for free to certain consumer groups.

The best opportunity for improving this situation is by taking the first step in a NRW-reduction strategy and start focusing on leak and theft detection within transmission mains.

That’s where Pure comes in.

With over 2,000 miles of large-diameter pipelines inspected, Pure Technologies has located more than 4,000 leaks for an average of 2.2 leaks per mile using our advanced inline leak detection technologies significantly reducing NRW while saving millions of gallons of water and helping prevent failures for utilities around the world.

Bloomberg TV Story

Initially, owners and operators perceived that once a pipe was constructed and buried, inspecting pipelines was not necessary as long as they were in proper working order. But with the trend of urbanization and development, the risk of operating these pipelines became greater, as leaks or failures can significantly threaten communities and the environment.

The challenge of managing aging pipelines that were not built with the thought of inline inspection is daunting. To best mitigate risk, oil and gas operators should use a multi tool approach that incorporates both real-time and survey-based condition assessment technologies.

SmartBall® leak detection for oil and gas pipelines is an innovative tool that can effectively compliment integrity programs. The tool identifies acoustic anomalies associated with leaks which differ from anomalies created by other sounds and pipeline features. SmartBall technology is highly sensitive and can identify leaks that aren’t typically found using other systems.

 

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Pipeline Leak Detection Systems

Pipeline Leak Detection Systems

Highly accurate inline leak detection systems that can detect leaks and gas pockets in operational pipelines. These systems are used primarily on larger diameter water and wastewater transmission mains of all materials as well as oil & gas pipelines.

Technical Paper

Development of a Long Duration, Free Swimming, Inline Acoustic Leak Detection Inspection Tool

Acoustic leak detection inspection tools have become a common technique to identify minute pipeline leakage before the leak and the defect producing it can become a larger problem or even a rupture level event. While these inspection tools only identify small defects once they reach the through wall stage and result in leakage, they can be an effective means of demonstrating the pressure tightness of a pipeline and ruling out the presence of through wall defects that are below the detection threshold of other ILI inspection tools; in so doing finding a way into both the leak detection and pipeline integrity toolboxes.

The York-Peel Feeder Main provides a critical supply of water for residents and businesses in The Regional Municipality of York. The pipeline is made of 1800-mm (72-inch) Pre-stressed Concrete Cylinder Pipe (PCCP) and runs roughly 25 kilometres (about 16 miles) through both Peel Region and York Region.

Although the pipeline was built in 2005 and is relatively young, York Region conducted two proactive inspections in April 2013 using advanced inline technologies to locate leaks, gas pockets and structural deterioration. Multiple stakeholders, including Peel Region, the Ontario Clean Water Authority (OCWA), York Region and local municipalities necessitated careful planning to minimize service disruption for end users.

Regular leak detection can help utilities identify leaks that may not be visible at the surface. These proactive repairs can help to reduce their non-revenue water and prevent pipeline failures, as leaks are often a precursor to pipeline failure. Locating and eliminating gas pockets also helps to reduce pressure on pumps attempting to pump water past an air pocket. As pockets grow in size, they can adversely affect the flow and capacity of a pipeline.

The SmartBall® leak detection tool was used to assess the pipeline for leaks and gas pockets and is often used as a precursor to electromagnetic (EM) condition assessment of PCCP pipelines. The SmartBall platform is a non-destructive, free-swimming tool that measures the acoustic activity associated with leaks and air pockets.
The tool was launched just downstream of the Airport Road Pump Station in Peel Region and was tracked successfully throughout the inspection and retrieved at the Maple Reservoir in York Region.

An EM inspection was completed on the pipeline using PipeDiver®, a free-swimming EM tool used to identify and quantify wire breaks in PCCP. The EM sensor collects a magnetic signature reading as the PipeDiver traverses the pipeline and identifies anomalies produced by wire breaks in PCCP, which are the main indicator that a pipe of this type will eventually fail. The tool is ideal for performing a baseline inspection of a PCCP pipeline that cannot be removed from service.

During the inspection, the PipeDiver was tracked through the pipeline as it passed 17 Butterfly Line valves of various designs and sizes. For retrieval of the tool at the Maple reservoir, a tethered robotic device was used in favour of a trained diver, which increased the safety and efficiency of the retrieval process.

York Region was pleased with the inspection process and will be completing follow up engineering analysis as the leak and gas pocket survey and EM results become available.

 

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Free-Swimming Pipeline Inspection

Electromagnetic Pipeline Inspection

Electromagnetic testing provides the best condition assessment data for large diameter PCCP (AWWA C301) and BWP (AWWA C303) pressure pipelines.

Smartball- Leak and Gas Pocket Detention

SmartBall® – Leak Detection for Water Trunk Mains

SmartBall® is an innovative free-swimming in-line leak detection technology designed to operate in a live water mains.

In January 2013, Lake Huron Primary Water Supply System (LHPWSS) verified the results of a condition assessment project completed in October 2012 that included leak detection and electromagnetic (EM) assessment. The verification allowed LHPWSS to proactively repair of three sections of Prestressed Concrete Cylinder Pipe (PCCP) along its major transmission main.

While the majority of Pipeline A – LHPWSS’s major water transmission that runs 47 kilometers (29 miles) – was found to be in good condition, the inspection showed seven pipe sections had a relatively high level of distress. Of these seven pipes, two were located within a twinned section and therefore had a lower consequence of failure.

The remaining five high-distress pipes were located within 3.5 kilometers (2 miles) of each other and are in the same vicinity of failures that occurred in 2010 and 2012. LHPWSS has since verified and replaced the three most distressed pipes from the five that didn’t have redundancy to mitigate the risk of another failure.

Although the pipeline is primarily in good shape, the identification of several highly-distressed pipe sections has allowed LHPWSS to proactively plan targeted rehabilitation to ensure the continued delivery of quality service and the prevention of a major pipeline failure.

Verification Tool
Excavated Pipe

By determining the baseline condition of their entire primary large-diameter pipeline, LHPWSS now has a better understanding of the overall health of their system and can make informed decisions as they move forward with their pipeline management program and the rehabilitation of their assets.

LHPWSS serves about 500,000 people in eight different municipalities in the London Region and provides about 170 million liters (44 million gallons) of water per day. Its major transmission main, the Lake Huron Pipeline A, runs from the Lake Huron Water Treatment Plant near Grand Bend, ON to a terminal reservoir located near the community of Arva, North West of the City of London and features mostly 1200-millimetre (48-inch) Prestressed Concrete Cylinder Pipe (PCCP).

 

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 Electromagnetic Pipeline Inspection

Electromagnetic Pipeline Inspection

Electromagnetic testing provides the best condition assessment data for large diameter PCCP (AWWA C301) and BWP (AWWA C303) pressure pipelines.

 SmartBall® – Leak Detection for Water Trunk Mains

SmartBall® – Leak Detection for Water Trunk Mains

SmartBall® is an innovative free-swimming in-line leak detection technology designed to operate in a live water mains.

In February 2012, The City of Montreal conducted a leak detection survey using the Sahara® platform on a water transmission main in downtown Montreal that had known leaks.

The pipeline on Pine Avenue is an 80-year-old, 34-inch cage and cylinder Bonna-type pipe – a variation of Reinforced Concrete Cylinder Pipe (RCCP) – that had an unknown number of leaks that were unsuccessfully located using other non-intrusive techniques during previous inspections.

The Sahara leak detection inspection was extremely successful, locating nine leaks ranging from small to large size in the 1.3-kilometer (0.8 miles) survey. The City was expecting to find one major leak and possibly another minor one and was surprised at the number of leaks identified.

The Pine Avenue pipeline is a critical supply of potable water to the western portion of a major sector in the city, which made it important for the City to locate and repair the suspected leaks.

The City had been working with Pure Technologies in pipeline assessment program since 2007 that included electromagnetic (EM) inspection and acoustic monitoring, which prompted the decision to use Sahara leak detection on Pine Avenue.

The Sahara platform is a non-destructive tool equipped with acoustic leak detection and inline video that is pulled by the water flow by a small drag chute and used to locate leaks, gas pockets, and internal pipe conditions in live, pressurized pipelines. When the sensor is inserted into a tap, it remains tethered to the surface to allow for confirmation of suspected leaks. The sensor is also tracked along the surface, allowing for precise marking of leaks in real time.

Regular leak detection surveys can help utilities identify leaks that may not be visible at the surface and may have been leaking for a long time. By repairing leaks, it reduces Non-Revenue Water and can potentially prevent pipeline failures, as the presence of leaks is often a preliminary indication that a pipe will eventually fail.

In August 2012, the City excavated all nine leaks for repair. The leak locations had been precisely identified and marked on-site during the inspection and all leaks were found within 1-meter (3-feet) of the marked location. All of the leaks also had a size that corresponded with the estimates made by Sahara technology.

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Pipeline Inspection and Condition Assessment Services

Pipeline Leak Detection Systems

Highly accurate inline leak detection systems that can detect leaks and gas pockets in operational pipelines. These systems are used primarily on larger diameter water and wastewater transmission mains of all materials as well as oil & gas pipelines.

Sahara® - Leak & Gas Pocket Detection

Sahara® – Leak Detection for Water Trunk Mains

Leak and gas pocket detection using a tethered acoustic sensor allows for real-time results, and maximum control and sensitivity.

Pure Technologies completed a 47 kilometer (29 miles) inspection of the Lake Huron Primary Water Supply System’s Pipeline A using the SmartBall® and PipeDiver® inspection platforms in October, 2012.

After two successful inspections of the 1200-millimetre (48-inch) water transmission main, LHPWSS commended Pure’s staff for their effort.

“The staff members at Pure Technologies were extremely professional and their level of expertise with respect to PCC pipe is phenomenal. Truly, they are leaders in their own field,” said Brian Lima, P.Eng., Capital Projects Manager for the LHPWSS.

A video overview of the project can be seen below.

PipeDiver Insertion
SBR Tracking

Pure was contracted by LHPWSS for a condition assessment of its transmission mains after a failure to a 1200-mm (48-inch) pipe in May, 2012. This was the fourth failure on the system; the others were in March 2010, 1988 and 1983.

After the most recent failure, LHPWSS wanted to take a proactive approach in inspecting and maintaining its water transmission mains to ensure quality service to its customers. The information collected from this condition assessment will allow LHPWSS to understand the baseline condition of its pipeline, as well as selectively rehabilitate pipes to minimize capital costs.

Before the condition assessment project, Pure and LHPWSS – which serves several member municipalities – developed a comprehensive project plan to ensure that all stakeholders understood the work involved and each group’s responsibilities, as well as how the inspections would impact each stakeholder.

Prior to the inspections, Pure installed 33 SmartBall receivers (SBR) along the pipeline to track both inspection platforms as they travelled through the pipeline.

For the SmartBall inspection, Pure’s team mobilized at the Lake Huron Water Treatment Plant very early in the morning to launch the tool. A small portion of the pipeline was isolated and depressurized to allow for manual insertion of the SmartBall. Once the tool was in position, the pipeline was put back into service and the SmartBall started travelling down the pipeline. After traversing 47 kilometers, it was retrieved in the Arva Terminal Reservoir by commercial divers.

After a day off to prepare the PipeDiver and discuss any lessons learned from the SmartBall inspection, Pure’s staff returned to the Lake Huron Water Treatment Plant for the PipeDiver Inspection.

“The launch, tracking and retrieval of the PipeDiver is very similar to the SmartBall. So the SmartBall was an excellent trial run for the PipeDiver,” said Cameron White, Program Manager at Pure Technologies. “The PipeDiver is a larger tool and is generally harder to get in and out of the pipe, so the SmartBall run gave us good practice for the PipeDiver.”

The PipeDiver tool was also retrieved at the Arva Terminal Reservoir with the use of commercial divers.

Both tools were tracked successfully at all SBR locations during the inspections. In addition, Pure provided the client and its member municipalities with real-time updates using an online interactive map and messaging system after it passed each tracking point.

“It’s been a pleasure working with [Pure] and we look forward to a long working relationship as we continue our endeavors into inspection and ongoing monitoring of our system,” added Lima.

The Lake Huron system serves about 500,000 people over eight municipalities in the London area and pumps about 170 million litres of water per day. The transmission main, constructed in 1966, runs approximately 47 kilometers from the Lake Huron Water Treatment Plant near the community of Grand Bend, to a terminal reservoir located in the community of Arva, North West of the City of London.

 

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Free-Swimming Pipeline Inspection

Electromagnetic Pipeline Inspection

Electromagnetic testing provides the best condition assessment data for large diameter PCCP (AWWA C301) and BWP (AWWA C303) pressure pipelines.

Smartball- Leak and Gas Pocket Detention

SmartBall® – Leak Detection for Water Trunk Mains

SmartBall® is an innovative free-swimming in-line leak detection technology designed to operate in a live water mains.

Introduction

In the past, the focus for leak detection programs in water delivery systems has been primarily on distribution (reticulation) networks and service connections. Even today, trunk main leaks tend to be addressed only when there is a pipe rupture or when there is visual evidence of the leak above ground. So are leaks from trunk mains a problem?

The introduction of a new leak detection technology, called SmartBall®, has the potential to resolve the uncertainty about the rate of loss, if any, from trunk mains. Following two years of development, the system has been available commercially since June 2007 and experience to date has demonstrated that it a valuable tool for identifying, locating and quantifying leakage. Results indicate that trunk main leakage is indeed a concern for many agencies, and that most leaks are not evident from visual inspection or metering.