SAN FRANCISCO (KTVU) - The San Francisco Water department is in a 90 day pilot project to evaluate high tech, "smart fire hydrants" that can also pinpoint underground water leaks. In just a short time, the meters have already paid off in smaller repairs and big water savings.
The 158 smart hydrants are monitoring a vast area, between 100 and 200 square blocks of Diamond Heights and Glen Park neighborhoods.
"They are listening for leaks in the water pipes that are so small, that we cannot detect them from above the ground. Even a very small leak can be leaking hundreds of gallons per minute," said San Francisco Water Department Manager Katie Miller.
The hydrants can find leaks, long before they become underground gushers that undermine the ground and cause pipes or joints to fail.
"We can actually go and proactively dig up the pipes, repair them before these leaks surface and cause a lot of property damage and disruption of our water service," said Miller.
The system can track more than leaky pipes. In fact, if you even have a leak in your house, it can track that leak all the way to your water meter and send you a notice that you have a water leak, inside your own property. The listening devices, called loggers, do their job in the wee hours of the morning.
"The loggers are listening between 2 and 4 because it's the time when everyone's asleep and in bed. So it's the period of least demand. So, any demand that happens during those hours, is most likely a leak," said water system engineer Brian Barry.
Because the sensors listen to the pipes several times during those hours, and automatically call in the results every night, the occasional toilet flush will not fool it. Then the number crunching and calculations take over.
"There's a team of engineers that look at it and then they try to pinpoint the leak within 5 to 6 feet to where we think the actual leak is before our leak detection crew goes out and investigates," said engineer Barry.
The leak crew, then uses a high tech listening device to precisely pinpoint the leak which speeds up repairs because not as big of an excavation is required and the leak is still more manageable. The post repair road patch is also often a tiny fraction of what it would have been before this system.
"We've already found four pretty good sized leaks that we have repaired," said Ms. Miller.
Major leaks, that occur two times a year on average, have caused millions in property damage This system will eliminate many of them as it is moved from one district of the city to another, rotating on a regular basis.