Water Loss Prevention Technology

You’ve tightened your faucets to make sure there’s no drip, drip, drip throughout the day. You may have even upgraded your appliances to water efficient versions. But what about the tanks, wells, and miles and miles of pipes that water travels through before it gets to you? What does San Jose Water do to prevent leaks and water loss on its end? The U.S. Environmental Protection Agency reported that the average water loss rate for water utilities across the US was between 16-20% in 2015. In comparison, SJW's average annual water loss rate is ~7 percent. We’re an industry leader in water efficiency and loss prevention and we’re constantly improving. Read on to see how we're using the latest tech to find leaks before they’re visible.

Water Loss Prevention Detection and Technology

SJW uses two cutting-edge technologies to identify where leaks are occurring.

  1. Acoustic leak detection sensors – We deploy mobile acoustic sensors throughout the service area. These help us identify and repair leaks while they're still small and before they reach the surface. Every night these sensors listen for acoustic anomalies. When anomalies are identified, an automated procedure correlates and maps the location of each suspected leak. Field staff then use this information to investigate and make repairs.
  2. Satellite-based leak detection – Satellite-mounted sensors orbit the earth to locate leaks in underground pipes within our community. Imagery is captured and processed using an algorithm that looks for a particular spectral signature typical to chlorinated drinking water in the soil. When a suspected leak is detected, this technology defines areas within which leaks are likely to be found. San Jose Water uses this data to investigate leaks in the field and to effectively deploy acoustic leak sensors in the water distribution system.
Satellite Map
click to enlarge

 

Water Loss Prevention Planning

Every year SJW performs a water loss audit for a data-driven approach to leak prevention. The system-wide water loss audit helps the team identify opportunities for continuous improvement. That audit and statistical modeling determines which sections of pipes are replaced based on which section of pipes have the greater number of leaks and which has the greatest probability of damage or failure. Every year, SJW replaces 1% of the buried infrastructure, which translates into 24 miles of pipe replaced each year! Using this combination of technology and planning, we're able to reduce water loss each year in our community.

Responding to and Repairing Leaks

As soon as we learn of a leak, we send an inspector to assess the severity of the situation. We rank leaks on a numerical scale and prioritize those that require immediate attention. The most severe leaks are determined to represent a serious hazard or a danger to public health or property. If a leak doesn’t require an immediate response, we place it on our maintenance repair schedule and send a crew to address it over the next 48 – 72 hours. We address most leaks within a week of identification. One reason it may take a few days to address a leak is that before we can dig we contact a utility location service to ensure we’re not disturbing power, cable, or telephone lines before we begin excavation. You can do this before you dig by calling 811. After nearby utilities have been marked we send out a crew to make the repair. It’s an involved process that requires significant resources, which is why we make every effort to keep our infrastructure in a good state of repair to avoid water loss. Like you, we believe water is a precious resource and we take its conservation seriously.