Levees are the weak link in California’s safe drinking water systems.
“A five year survey released by the California Department of Water Resources reveals half of the levees that guard California cities from a major flood don’t meet modern standards, and if a levee were to break in the wrong place, it could cut off the drinking water supply to the Bay Area for months or even years,” NBC News Bay Area reported.
The report, which is meant to assist flood management planners and engineers around the state, showed that, to an alarming extent, drinking water is insecure as a result of aging levees and underinvestment in modernizing them.
“The report also indicates 60 percent of the levees that protect the state’s rural areas from flooding — roughly 1,230 miles in all — are at high risk of failure from seepage, boils, structural instability, erosion and even rodents; that includes the levees that protect the drinking water aqueducts for the Bay Area and Southern California,” the report said.
The state has 13,000 miles of levees, the news report said, and many of them were built in the 19th century.
Michael Mierzwa, the lead central valley flood management planner with the state Department of Water Resources, highlighted the problem of underinvestment in infrastructure.
“The levees are old,” he said, per the report. “We’re sitting on levees that were constructed over a hundred years ago, and we haven’t been really paying the true cost on maintenance and upkeep.”
So, just how vulnerable is drinking water as a result of the levee system?
“A major flood event could knock out that aqueduct system, which would contaminate the fresh drinking water supply with salt water and destroy the vessel that delivers that water to homes and faucets throughout the state,” the report said.
Mark Cowin, former director of California’s Department of Water Resources, summed up the problem like this: “The threat of levee catastrophe is significant. We depend upon the integrity of those levees in the delta to allow us to move the water from north to south.”
Californians had a major wakeup call about their flood infrastructure over the winter after intense flooding followed years of drought in the state. Water infrastructure systems were heavily taxed in the process. Along with evacuations near the Oroville Dam, the rain and flooding “stressed thousands of miles of levees and flood infrastructure downstream of the major dams,” KQED reported.
For similar stories visit Water Online’s Asset Management Solutions Center.
Image credit: "Water Faucet," Rose Mary © 2014, used under an Attribution 2.0 Generic license: https://creativecommons.org/licenses/by/2.0/