By Jason Barlow

The Town of Smiths Falls is a vibrant, progressive single tier municipality with a population of 9,000. One of Eastern Ontario’s most scenic communities, it is centrally located within an hour of Ottawa, Kingston, Brockville and the U.S. border. The town’s water system serves the residences and businesses in Smiths Falls, as well as a portion of Montague Township. Constructed in 2010, the water treatment plant has a maximum design capacity of 14,000 m3. It provides treated water through a system of approximately 62 km of underground pipes, which range from 100 mm – 550 mm in diameter. These are from 10 to 100 years old and are comprised of various materials, including cast iron, ductile iron, polyvinylchloride, concrete and steel.

Non-revenue water (NRW) is the difference between the volume of water supplied to the system and the volume of water billed to the customers. It is water loss for which the utility receives zero revenue A series of water audits conducted in late 2018 began the annual process of calculating Smiths Falls’ NRW. These found that NRW levels were above 60%. Consequently, the town’s water department began searching for a solution that could be used to reduce its NRW levels by accurately and efficiently detecting leaks in its water system. In 2019, after a service sustainability review of system operations, the conclusion was to place a priority on NRW and target the system’s water losses to increase efficiency.

Some of the benefits of NRW reduction, in particular leakage reduction, include financial gains from increased water sales/ reduced water production costs, increased knowledge about the distribution system, reduced property damage, reduced risk of contamination, and more stabilized water pressure throughout the system. The town was repairing four to six watermains annually, and only making repairs when water was surfacing or found within the sewer systems during maintenance activities.

In 2020, the town purchased Echologics’ Leakfinder-ST correlation equipment, to assist with the search for areas of concern. This equipment was chosen since, within the water system, 95% of all the leaks/breaks were not surfacing. After the purchase and training on the correlation equipment, the town started surveying areas that were identified as having leak noises. The initial survey was conducted by operation staff with their geophones. These devices consist of a brass disc (puck) connected to a rubber/ plastic tube with ear pieces that are like those on a stethoscope. While using the correlation equipment, the number of service line leaks increased. During the investigation, the team was able to narrow in on the source of them and make the necessary repairs, or to work with the property owners for repairs made on private portions of the service lines.

Of the 22 watermain breaks and 14 water service repairs completed in 2022, only two of these were identified by surface discharge. All of the other repairs were found utilizing the Leakfinder ST. Efficiencies were also created utilizing automatic flush stations throughout the distribution system. This allowed the town to remove the old bleeder valves, which would run 24 hours a day 7 days a week. This means more managed flushing of the areas of concern, which increases and establishes a consistent water quality. While the distribution team was finding and making repairs within the distribution system, the water treatment team was also finding efficiencies in facility operations. These include reduced flows in the systems and enhancing the treatment operation. Reduction in filter backwashes and backwash operations, as well as more consistent UV operation to reduce the amount of cooling water utilized, has led to a reduction of more than 50,000 m3 of process water annually.

Through facility communications and tools such as Google Data Studio, the team has been able to continually track water plant flows and react when a higher flow trend is realized. This increases the effectiveness of leak detection and decreases costs. Repairing a leak before it becomes a break saves rehabilitation costs. A total of 806,021 m3 of water has been removed from the town’s NRW totals between 2018 and 2022. The average daily flow at the water treatment plant was 6,988 m3/day in 2017. In 2022, the plant saw an average flow of 4,776 m3/ day, which is a reduction of more than 2,000 m3/day over a four-year period. The trend of NRW reduction is continuing in the early months of 2023, as average flow rates of 3,600 m3/day are being realized. This is a savings of another 1,000 m3/day of water loss. The Town of Smiths Falls has been able to realize energy savings of 300 – 650 kWh/day, along with chemical (coagulant) savings of up to 30,000 kg/ year with the reduction of non-revenue water volumes within its system.

Click here to read the article in Environmental Science & Engineering