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Phoenix Water Services tests system constantly to stay ahead of potential failures

Water is something we take for granted, even though we live in the desert. You can turn on a faucet at home and you expect water to come out. The reality is bringing water to your home is an immensely complex task and it's possible for the system to fail with disastrous consequences.

Here's what can happen when a water main breaks: a flood. This happened on the University of California in Los Angeles. Buildings turned into impromptu fountains -- water poured into basements and flooded UCLA's basketball arena. The court was under water.

"They had a large, pre-stressed concrete pipe that had a failure.. large pipe and pressure released large volumes of water in a place with a lot of depressions, so all the water was funneled into the basements and garages and everything," explained Troy Hayes from the Phoenix Water Services Department.

This was a spectacular failure, but the threat is always there. That's because water mains form a web under the streets of every city, including Phoenix.

"Well, you think about it, we have water mains up and down every street. There is a six-inch main bringing water in your house every day. 7,000 miles of water main for 540 square miles of Phoenix," said Hayes.

Phoenix Water Services is constantly trying to stay ahead of any potential failures -- testing the system for weak spots and replacing pipes on a regular basis.

We caught up with a crew near Van Buren and 12th Street.

"Unless they are digging in front of your house, most people don't know what we are doing with the water system. It is very seamless and they don't see it," said Phoenix Water Services' Aimee Conroy.

It isn't always old pipes that need to go.

"There are 106 year-old mains still as good as day put in.. very strong, if not breaking, I wouldn't be concerned," said Conroy.

Some of the most crucial pipes are the ones that carry water out of the city's treatment plants. Those pipes are the biggest in the sytem.

The biggest pipe in the Phoenix water system is 108 inches in diameter -- that is nine feet. One section weighs 70,000 pounds. That's a pipe that better not fail.

"It can be very catastrophic, but that is why we continue with our inspection and assessment program to possibly prevent a failure," said Phoenix Water Services' Mario Brown.

No leaks is the goal and no contamination either -- like in Flint, Michigan -- the water system disaster that shocked the whole country.

Good news on that front: no lead contamination in Phoenix water and no lead pipes in the system.

The oldest pipes in the Phoenix water system are over 100 years old and are made of galvanized steel. The newer ones are made of iron.