14 July, 2014

The Art of Water Recovery - NYTimes.com

The Art of Water Recovery - NYTimes.com: “When you have a pressurized system, what you do in one place affects all other places,” said Meir Wietchner, Miya’s chairman. Replace a leaky pipe segment and the pressure will increase in other segments and more leaks will sprout.

“It’s simple physics,” he added. “And the larger the pressure the larger the leakage. If a hole that’s receiving one unit of pressure will leak X gallons per day, with 2 units of pressure it will leak 4X, and with 3 units pressure it will leak 9X. It’s a square function.”

One of Allan Lambert’s insights was to separate leaks into “bursts” and “background” losses (pdf). “It isn’t the main leaks that cause the most loss of water,” he said. “It’s the long-running leaks that go on for months or years that aren’t detected. One leaking toilet will lose as much water in two years as a burst in a four-inch main for a full day.”

So how do you fix and manage a system that’s leaking in tens or hundreds of thousands of places — and how do you do it cost effectively?