In the wake of Hurricane Katrina, California politicians and flood control agencies are crying out for billions of dollars to reinforce 1,600 miles of levees and modifications to a key dam that protects the Sacramento-San Joaquin Delta and Southern Californias water system.
"This is a wakeup call, I think, for every state in the country, to not postpone things," says Gov. Arnold Schwarzenegger (R). "If we know there is vulnerability, let us fix it now."
|Future Past. A Delta levees remain at risk after a June 2004 break caused $100 million in damage. remains at risk.|
The vulnerability of what is rated a 100-year flood protection systemjust half of the 200-year protection in New Orleanswas illustrated last year when a levee failure west of Stockton flooded 12,000 acres of farmland and caused $100 million in damage (ENR 7/12 p. 7). Even more dramatically, a 1986 storm dumped 10 in. of rain on Sacramento in 11 days. That caused record releases of as much as 135,000 cu ft per second from the Bureau of Reclamations Folsom Dam that led to a levee break in Yuba County, flooding dozens of homes. Since then, Sacramento Area Flood Control Agency and local politicians have crafted a plan to upgrade to 200-year flood protection by enlarging the gates at the concrete-gravity structure to allow earlier release and upgrading levees to accommodate the flows.
But the Army Corps of Engineers Folsom Dam Upper Tier Outlet Works Modification Project floundered in June. Bids to enlarge four of the eight 5 x 9-ft slide gate outlets to 9 ft, 4 in. x 14 ft and add two new ones came in nearly three times more than the solicitation range of $100 million to $250 million estimated by Denver, Colo.-based Project Time & Cost Inc.
Kenneth Myers, vice president at Omaha-based HDR Engineering Inc., one of the companies bidding on the Folsom project, blames the increased cost simply on risk. "There is a tremendous amount of risk involved in working on a live dam and the (fixed-price) bidding process put all the risk on the contractor," he says. Crews would have to work underwater at depths of 220 ft on the inner face of the dam, ensuring flood protection during the entire process. Higher-than-expected increases in steel and concrete prices may also have had an impact. A Corps spokeswoman says the agency is reviewing options.
The California Dept. of Water Resources is still struggling to improve levees between the Sacramento-San Joaquin Delta and the Bay, many of which were built in the late 1800s using wheelbarrows to pile silt and sand on loamy peat riverbank foundations. Some 1,000 miles of levee are still privately owned and maintained to standards lower than required by the Federal Emergency Management Agency. The Corps of Engineers has grandfathered them into the system while it performs an inventory of requirements to bring them up to FEMA standards. Seepage has been discovered in large areas and DWR is trying to determine the extent of the problem.
Fixing the system could cost $2 billion or more, says Ricardo Pineda, DWR floodplain manager. One bill that addressed the problem died in the state assembly days after Katrina hit the Gulf. It contained flood-insurance requirements and tax powers for maintenance districts but was opposed by taxpayer groups. A proposed transportation bond for the November 2006 ballot could contain $1 billion for inspections and levee strengthening.
(Photo by California Department of Water Resources)