Remote Pressure Reducing Valve (PRV) Monitoring Reduces Water Main Breaks and Damage
Reduce water loss, save maintenance and energy costs, and minimize customer disruption
By Tom Garrity, Director of Sales, Ti-SALES
Water main breaks are among a water utility’s least favorite challenges: they’re disruptive to both the utility and the customers it serves, they waste water and lead to high non-revenue water (NRW) numbers, and they’re costly to repair and can adversely impact public health. But what causes water main breaks, and more importantly, how can they be reduced and controlled?
The Effects of Water Main Breaks
A commonly cited statistic claims that 850 water main breaks occur each day across North America – but that number may be even higher. According to a 2018 study by Utah State University – which studied nearly 200,000 miles of pipe from 308 utilities over six years – water main breaks are on the rise as North American water infrastructure declines. Break rates increased by 27% between 2012 and 2018 – and what’s worse, break rates for cast iron and asbestos cement (AC) pipe were up over 40% in that same period.
Water main breaks are expensive to fix, in the hundreds of dollars on the low end (minor repair in an easy to access location) to thousands of dollars for major repairs or those in inaccessible locations. Repairs can take anywhere from a few hours to days or even weeks to fix, upsetting customers and commuters alike. Even more concerning, breaks can introduce contaminants to the local supply of drinking water, including harmful toxins and bacteria that can harm residents unlucky enough to have been drinking the water before the break was discovered.
Water main breaks can also cause property damage. While most breaks are small – certainly not the fountain of water in the middle of the street most people picture – the water can cause erosion in the area, create sinkholes, damage roads, and invade basements. All in all, water main breaks are a headache for any utility or public works department!
Causes of Water Main Breaks
Water mains are subject to all kinds of stresses, both from construction in the area (vibrations, accidental strikes) and from normal temperature changes. A drop in temperature causes the ground to contract, putting pressure on pipe; hot temperatures, on the other hand, make the ground shift and settle, which can warp pipe.
One of the biggest contributing factors to water main breaks is, unsurprisingly, aging infrastructure. The 2018 Utah State University study found that 82% of cast iron pipe and 27% of AC pipe used in water systems is over 50 years old. All materials wear out in time, becoming more fragile or brittle depending on what type of pipe it is; cast iron is particularly prone to cracking with age.
Corrosion is also a major cause of water main pipes: highly corrosive soil dramatically increases the break rates, especially in cast iron and newer thinner-walled ductile iron pipe (even with corrosion protection).
Changes in pressure also put a lot of stress on pipes, which are designed to operate within specific pressure ranges. When an area grows in population, so too does its need for water, and it’s easy for a system to be slowly but surely pushed past what it was designed for. Sudden fluctuations in pressure are even more taxing on pipe; municipal water systems rely on a system of pressure regulating/pressure reducing valves (PRVs) to reduce and control these fluctuations.
Case Study: Erie County Water Authority
In 2021, we worked with our customer Erie County Water Authority (ECWA) to help reduce and control their water main breaks. ECWA supports almost one million residents in upstate New York; their distribution network includes more than 600 miles of water main pipes. An aging system of pipes, combined with the regional temperature variations of upstate New York, meant that they were facing approximately three water main breaks daily and over 1,000 breaks annually.
One of ECWA’s challenges was the fluctuating demand created by Highmark Stadium, home to the Buffalo Bills. During football games and events, the stadium hosts over 70,000 fans, creating a substantial demand for water; when no events are in progress, the demand is almost zero. A PRV controls the water pressure to compensate for the extreme change in demand; however, the extreme fluctuations put a lot of wear on the PRV. When that PRV isn’t functioning, the pipeline it serves bears the load of those fluctuations, creating leaks and breaks.
Working with our partner Ayyeka, we helped ECWA implement a remote monitoring solution using Ayyeka’s Wavelet device to continuously monitor the pressure levels on critical PRVs throughout the water distribution system. By taking measurements every ten minutes, the device can identify abnormal pressure events in real time and send immediate notification to ECWA water professionals. “When pressure drops, we need to act immediately to isolate and locate the leak,” said Clayton Johnson, PE, of the Erie County Water Authority. “The quicker we find the leak, the less damage is done to pipes. This usually lets us patch the pipe instead of beginning a costly pipe replacement. The Ayyeka solution pinpoints where the pressure problem is, leaving a much smaller area to search for the leak. This also leaves less residents without water while we fix the pipe.”
Optimizing pressure in PRVs in the water distribution network has reduced unnecessary stress on pipes and leads to dramatic savings in maintenance and energy costs. Real-time monitoring pressure levels enables water engineers to act immediately and proactively instead of just responding to breaks and other emergencies. What’s even better, the data from the Wavelet devices also seamlessly integrate with ECWA’s SCADA system, giving water professionals the information they need to anticipate trends and create optimal hydraulic models.
Summing Up…
Water main breaks aren’t going away any time soon: aging infrastructure and increasing demands on distribution networks suggest this particular challenge will only be growing in the near future. It’s almost never feasible to replace every piece of a system that’s past its prime (or advisable!); however, remote monitoring devices implemented at key points in the system, such as critical PRVs and similar infrastructure, can help a utility make the best use of its resources by pinpointing the source of its immediate problems – and by anticipating future problems before they disrupt service.
We’d love to help you reduce water loss, save maintenance and energy costs, and minimize customer disruption by reducing your water main breaks; please reach out with any questions.
Tom Garrity is the Director of Sales for Ti-SALES, a leading distributor of water and wastewater supplies and supplier for Ayyeka’s Wavelet remote monitoring device. The Wavelet is a full-stack hardware, software, and service solution enabling data collection from any sensor, over any communication network, using any server, and can be integrated into any SCADA or software analytic platform.
Case study information provided courtesy of Ayyeka, in collaboration with Erie County Water Authority.