Quake on San Andreas Fault Could Threaten Water Supply

Geology expert Pat Abott said the state needs to start long-range thinking when it comes to aqueducts and fault lines

When an earthquake hits, there's more to worry about than meets the eye - especially in a drought.

NPR reported Saturday that a 7.8 magnitude quake on the San Andreas Fault could sever all four aqueducts at once, cutting off more than 70 percent of the water sustaining Southern California.

Professor Emeritus of Geology, San Diego State University Pat Abbott explains that much of our water supply crosses over one of the earth's most active fault systems

“We have to have the water. And it's in danger of being cut off by a major fault movement,” Abbott said.

Much of Southern California’s water comes from aqueducts in the northern part of the state. The problem is that those channels run over the San Andreas Fault.

An example of potential damage can be seen in the 1857 Fort Tejon earthquake, Abbott said.

“The land shifted horizontally 30 feet in 2 minutes. Well, a 30-foot horizontal offset of an aqueduct,” he said. “Boy, that's going to take some time to clean-up and cause a lot of mess in the meantime.”

Repairs could take a crucial amount of time especially when you're talking about cutting off water to countless homes and businesses.

When it comes to our water supply being in danger, costly long-term projects will be worth it, Abbott said.

“We're going to spend tremendous amounts of money and difficulty but the people of California are not going to be left to perish for lack of water,” he explained.

In the San Diego area, more water storage is possible after additions to the San Vicente Dam which is located west of the fault.

Read how the city of Los Angeles is planning to serve citizens with water in the case of such an interruption in the NPR report here.

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