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Chuck Hansen, Chairman & CEO at Electro Scan talks to World Water-Tech North America about its successful leak detection technology and different changes water utilities are facing.
What changes are you seeing at water utilities given historic drought conditions and wet weather events that cause major flooding?
As climate change exaggerates the frequency of droughts and floods, water utilities are making dramatic changes in their approach to managing their infrastructure, especially in the area of water losses and leakage reductions. Water utilities know that they can’t manage leaks they don’t hear and can’t manage water losses they don’t see.
Traditionally, age, break history, and pipe material were used to identify repair & replacement programs. Sometimes prioritizing pipe replacements on a first in, first out basis; meaning the oldest pipe were scheduled for replacement, first. But, as more utilities found that water loss and leakage are driven more by who installed the pipe and how, rather than the year the pipe was installed, utilities are turning to new technologies, like Electro Scan, to assess 360-degrees of an entire full-length pipe. Since most leaks are not heard and missed by acoustic sensors and listening devices, Electro Scan is unique in its ability to find leaks and measure pipe wall loss, especially in cement and cement-mortar lined metallic pipes. Also referred by the EPA as Focused Electrode Leak Location or FELL, Electro Scan has already gained international acceptance from a number of standards boards and adoption by key international utilities like San Antonio Water System (US), Sydney Water (Australia), and Southern Water (UK).
How have acoustic sensors and other listening-based tools missed so many water leaks?
We all know that acoustic data loggers, data correlators, and listening sticks, were the backbone of most water utility leak location programs. Credited with finding easily identified leaks (i.e. the low-hanging fruit), but not able to determine each leak’s actual severity as most readings were above ground, with pipe located at different depths, different pressures, and carrying water through different pipe materials.
Listening for high-pitched sounds in a pressurized pipes, field crews and remote sensors mostly found smaller leaks. With surveys scheduled late at night or early morning, larger leaks were frequently missed on the same pipe, disguised by air pockets, ambient noise, customer usage, high groundwater levels, low water pressures, multiple leak noises, and ponding water surrounding the pipe leak. Newer pipe materials, like plastic or polyethylene, also make it nearly impossible to correctly locate leaks, representing nearly 75% of all new pipe installations. After fixing a leak, crews would often return to the same pipe multiple times after ‘new’ leaks were found. Smart utilities understand that ‘where there is smoke, there is fire’ but continued high levels of water losses tracked to individual DMAs showed longstanding flaws in acoustic technology, often unable to repeat its results hours, days, or weeks, after original anomalies were found.
What makes Electro Scan technology so different from legacy leak detection technologies, like acoustic and electro-magnetic sensors?
Electro Scan measures the size of the hole, no matter how small, and is based on the scientific properties of electric current. Used by the oil & gas industry for nearly 50 years to assess external pipe coatings from above ground, Electro Scan’s in-pipe tethered-based machine-intelligent multi-sensor probe assesses pipe condition and leaks below ground from inside the pipe. Contrary to traditional leak detection technologies that listen for water exiting a pipe, Electro Scan uses low voltage current to locate all the holes or openings in a pipe wall (with 1cm or 0.4in accuracy) that allows electricity to flow through a crack or hole. Independent of pipe flow, pipe material, and pressure, if electricity leaks through a pipe, water does, too [Ohm’s Law]. And, given the size of the hole and pressure, cloud analytics can measure the rate of each’s leak flow in gallons per minute or liters per second [Torricelli’s Law].
How does Electro Scan compare to acoustic sensors?
Our multi-sensor probe, called DELTA, includes both an acoustic sensor (provided by a well known third-party) and Electro Scan’s low voltage electrical sensor. That means DELTA is able to benchmark Acoustic and Electro Scan on every survey. We also have a 4k CCTV camera that I’ll talk about later. We originally thought we were taking a belt, suspender, and rope approach to hold up our pants and find leaks. Instead, we found most acoustic anomalies were false positive readings that weren’t leaks. And, these weren’t exceptions. This was on every benchmark showing acoustic in-pipe sensors were missing 80-100% of leaks found by Electro Scan.
A framework contractor in London, England was unsuccessful finding leaks – attributed mainly to low water pressures in plastic pipes. Already passing Materials in Contact (MIC) regulations in the UK for entering drinking water networks, we were asked if we could remove our acoustic sensor on the DELTA and just have CCTV and Electro Scan. A new push reel system was created, called TRIDENT, where multiple 90-degree bends could be navigated to electro scan the pipe, using CCTV to navigate calcification, debris, and obstructions, traveling up to 350 feet (120m).
Beyond leak detection, Electro Scan determines pipe wall thicknesses by measuring electrical resistance – something acoustic and electro-magnetic sensors were never designed to do – and can determine the porosity of pipe walls. Given ‘unexplained’ water main breaks and burst pipes, Electro Scan can now provide an early warning alert identifying which pipes will most likely burst, especially for Asbestos Cement (AC) and Pre-stressed Concrete Cylinder Pipes (PCCP).
You mentioned using a high-resolution CCTV camera inside a water pipe. What role does CCTV play?
We all know that CCTV cameras are not able to find leaks. Not even in gravity sewers or storm drains. Since most leaks in sewers are at cracks and joints, the inability to ‘see’ whether a pathway exists from inside to outside of a pipe eliminates CCTV as a viable tool to identify infiltration. This is a major reason that utilities have de-emphasized CCTV inspection, much to the surprise of recently VC-backed companies that specialize in automated review of CCTV videos.
For water network, CCTV never gained traction as a leak detection tool. Especially since leaks tend to exit a pipe, not enter a pipe (i.e. unless low water pressures cause contaminated external sources to get sucked into a pipe).
Again, Electro Scan discovered something significant. While some early providers attempted to continuously televise the inside of a pipe, Electro Scan was already showing where the leak was located. Since data is displayed on a real-time basis, leak locations are easily identified. After a probe reaches the end of the survey and retrieval begins, operators already know where leaks are located and able to stop the camera at the same position. By lingering & loitering at a defect location, something amazing happens that is missed by continuous CCTV video. Particulates floating in the water can actual be seen moving towards the direction of the leak, allowing clock positions to be identified for individual leaks. Using AI to map the movement of particulates gives us one more way to confirm pipe leak locations, so we are assured above ground field crews know where to mark “X” to dig.
Before we wrap up, we understand that you and Mike Simpson, from M.E. Simpson will be speaking on a World Water-Tech panel on locating lead service lines. Can you share a preview of your session?
Sure. In December 2021, the U.S. Government passed a landmark law giving financial support and incentives to eliminate 100% of all lead service lines in the United States. Funded by US$15 billion the Bipartisan Infrastructure bill is being administered through individual state drinking water agencies, with first year allocations based on the population size of water utilities and subsequent years based on identified needs. All drinking water suppliers must inventory all lead service lines by October 16, 2024.
About five years ago we started seeing Asbestos Cement pipes with readings that were not leaks. In these cases we found that melted lead was used to seal the joints. Since Electro Scan measures the change in electrical resistance, as our probe moved from cement to lead to cement pipe material, we saw that we were passing lead soldered joints.
Fast forward to the 2020 U.S. election of President Joe Biden and during the height of the COVID pandemic, legislation began to accelerate that would require drinking water suppliers to identify and remove lead services, in part due to lead contamination found in Flint, Michigan.
A 2020 study sponsored by the Water Research Federation identified ‘electrical resistance’ as the only technology able to successfully tell the difference between lead, copper, and other metallic pipes in a laboratory. Electro Scan already knew it could find lead in active water mains, but hadn’t transitioned its probe to smaller diameter pipes or navigating ½ inch (25mm) diameter pipes. The bigger obstacle was needing was needing to assess both pressurized and non-pressurized pipe, and navigating multiple 90-degree bends. The result from our team of water experts, engineers, and data scientists was SWORDFISH, the world’s first lead pipe detection system.
Who in your organization has been most responsible for the success and adoption of Electro Scan technology?
Mike App, VP of Worldwide Operations, and Brad Weston, Managing Director of Electro Scan (UK) Limited, deserve much of the credit for the adoption of Electro Scan’s solutions.
Mike App’s experience in trenchless technologies showed him that pipe renewal projects did not always prevent continued home flooding issues. At Electro Scan, Mike has spearheaded over 1,000 certification tests covering nearly 50 suppliers and found that some pipes leak more after rehabilitation due to poor re-openings of tap connections. This has led smart utilities to change their acceptance criteria for new and relined pipes.
Brad Weston’s work in England, especially in dealing with Ofwat regulatory requirements and Asset Management Plan (AMP) 7 challenges, has driven major rethinking in the UK water sector. Weston’s leadership in pressurized pipe assessment led to Electro Scan winning the 2021 PETRONAS TECH CHALLENGE for underground pipe assessment, bringing Electro Scan squarely in the middle of the environment & energy nexus, a gap not bridged by any other company in the pipeline space.
Hear more from Chuck at the World Water-Tech North America Summit. He will be speaking on the Infrastructure Innovation: Solutions for Lead Pipe Detection & Removal panel on Thursday September 29 at 10am PST. For more information about Electro Scan, visit their website here.