The U.S. Army Corps of Engineers, which periodically inspects California’s Central Valley flood-protection network, released a report card on 10 of the state’s 26 levee systems, rating seven as “unacceptable” and warning some problems would “likely prevent performance in the next flood event.”
Issues cited included encroachment, underseepage, vegetation and slope stability. The other three won “marginally acceptable” ratings; they retain eligibility for “active” status in a federal “rehabilitation and inspection” levee safety program and may receive federal aid to repair flood damage.
The Corps is using $4.6 million in American Recovery and Investment Act funds to contract with GHT2—a joint venture led by Genterra Consultants Inc., Irvine, Calif.—RJH Consultants, Englewood, Colo., and URS Corp., San Francisco, to review maintenance records and visually inspect the levees, which funnel 7.5 million acre-ft of water to 20 million people in Southern California.
An eight-mile stretch of American River levees in Sacramento was among the unacceptable, due to encroachment and seepage; however, because the region now is spending $60 million on 18 miles of the system to address many issues cited, it will retain active status in the program.
Tim Kerr, general manager of the American River Flood Control District, co-manager with the city and the California Dept. of Water Resources, says the Corps has changed rules on vegetation, making some sites out of compliance that otherwise would have passed.
With unacceptable grades, other areas in Stockton, Yuba City and Manteca as well as two stretches of the Marysville Levee District fell into “inactive“ status in the program. Results for the 16 remaining districts are due this winter.