Electro Scan Inc. and James C. Hailey & Co., Consulting Engineers (JCH) have been working collaboratively on sewer infiltration and non-revenue water (NRW) issues in Tennessee since 2018. Over the past four years, numerous projects have been undertaken and none more important than the issues with water loss in Spencer, Tennessee.
The City of Spencer, is a rural underserved community that Nathaniel Green, P.E., of JCH has been working with since 2012. The City has been having water loss issues and has tried numerous inspection methods without success finding the sources of its NRW. The City has an extremely limited budget and needs cost-effective and reliable solutions to mitigate its NRW in order to conserve water and save taxpayer money.
The City’s Utility Department serves more than 5,000 residential customers. Located in Van Buren County, approximately 100 miles southeast of Nashville. The City of Spencer owns and operates more than 100 miles of distribution mains.
In November 2019, the City was awarded a grant of more than $600,000, authorized under the Water Infrastructure Improvements for the Nation Act (WIIN). The WIIN Grant provides much needed assistance for public water systems in underserved, small, and disadvantaged communities to help meet Safe Drinking Water Act (SDWA) requirements.
“The WIIN grant provides the City with funds for planning, design, and related technical assistance in preparation for improvements to the existing water treatment plant and distribution system, as well as addressing long-term water supply considerations to maintain its compliance with the SDWA,” explained Green, the City’s outside consultant with JCH.
The ability to use an emerging technology such as Electro Scan’s DELTA and TRIDENT for an underserved community and know with certainty that the water loss issue does not lie in their raw water line. Normally this more than 8,000-ft section of ductile iron pipe would have been replaced strictly due to age, and lack of results from other inspection methods. This project provided results not previously available and gave data with enough accuracy to prevent an unnecessary large scale construction project.
Electro Scan’s scope involves assessing the oldest section of pipe, installed in 1988, and evaluate its remaining service life. The City’s current primary raw water supply is a man-made reservoir. This reservoir is filled from a pipeline that pumps water from the Caney Fork River to the reservoir, where it is stored prior to being directed to the water treatment plant.
“Recent droughts and difficulty with source water constituents led to the determination that Spencer should upgrade its emergency raw water source in order to meet the City’s water demand full-time,” continued Green.
“We are excited to support the City of Spencer with this innovative condition assessment”, stated Electro Scan East Coast field manager Mackenzie App. “The ability to assess 9,000 ft of critical pipes in just two to three days, and provide the inspection data back to the City and its consulting engineer, James C. Hailey & Co., Consulting Engineers, within minutes is imperative to assessing pipeline conditions.”
As with many underserved, small and disadvantaged communities, the City has excessive NRW losses. In addition to the 10-in. pipe inspection, Electro Scan’s TRIDENT probe will be used for selected pipe inspections throughout the town known to show excessive NRW losses. The ability for low-voltage conductivity to show where “X marks the spot” is a powerful tool to allow the City to target critical pipe rehabilitation or replacement and reduce unnecessary capital costs.
The technology locates pipe leaks to within 3/8 of an inch and reports the leakage rate in gallons per minute (GPM). The low-voltage inspection work conforms to the American Water Works Association Manual of Practice #M77, “Condition Assessment of Water Mains.”
Using both its patented DELTA and TRIDENT Multi-Sensor probes, the Company evaluated the pipeline conditions for these key potable distribution mains. The truck-mounted tethered DELTA probe combines Electro Scan’s patented low-voltage conductivity technology with closed-circuit television (CCTV) and acoustic measurements. The manual hand push-reel TRIDENT reel is fitted with low-voltage conductivity and a high-definition CCTV camera.
The City was able to save more than $1 million in construction costs, by determining that there were no major issues in the Raw water line. The line is more than 7,000 ft of ductile iron pipe, that was slated for replacement due to its age. The DELTA scan was able to pick up a few individual anomalies that can be addressed in lieu of replacing the entire line as originally planned.
This project has numerous positive business results, for JC Hailey and the City of Spencer. The City was able to use a SEARCH grant to help kickstart this process and utilize the Electro Scan DELTA and TRIDENT tools to uncover information about their raw water line that allowed them to delay replacement and focus their leak detection efforts elsewhere. It has allowed the city to bring in more grant money to help rehabilitate water infrastructure in an underserved rural community.
“We plan on using Electro Scan more in the city later this year or early 2023 as we begin the investigation of the city’s distribution system. We wish to Thank Electro Scan for offering their expertise, personnel and tools (DELTA and TRIDENT ) to this project. It is great to see companies willing to work with small communities and their issues,” stated Green.
This is not the first project Electro Scan has undertaken with small rural communities. In 2019 Electro Scan surveyed more than 120,000 lf of sewer with its ES 620 for the Town of La Grange, North Carolina. La Grange is similar in size, and economic issues as Spencer. La Grange was the recipient of a $9 million low interest loan from the U.S. Department of Agriculture.
Electro Scan was locally supported throughout the project by Tim Kazmier and Alex Tweel, with the Lenoir, Tennesse-based Kazmier & Associates, an Electro Scan’s business partner in Tennessee.