The levee protecting East Palo Alto from San Francisquito Creek during potential winter storm flooding is not certified to withstand a 100-year flood and could fail, according to a report released Thursday by the San Mateo County Civil Grand Jury.
The levee was repaired last fall, City Manager Alvin James said. The $470,000 project included inserting an 8-foot wall 2,000 yards long into the earthen berm to strengthen it. Repairs were also made to stop erosion.
James said the levee, which was built in the 1950s, does not qualify to be certified for a 100-year flood. "It would have to be higher or the channel deeper," he said.
The grand jury also found that 12 dams in San Mateo County that "pose high or significant risk in the event of failure," including the dam on Searsville Lake in the Stanford foothills.
Failure of dams or levees could threaten up to thousands of lives, as well as homes and businesses in San Mateo County, the civil grand jury reported.
According to the report, though the county Office of Emergency Services and Homeland Security has a warning system, there is little information about the maintenance and structural integrity of the dams and levees, as well as a lack of emergency plans in case they fail.
"Not a single Emergency Action Plan has been prepared and submitted to OES/HS or the state by dam and levee operators, although the State Office of Emergency Services has the authority to mandate them," the civil grand jury report stated.
The civil grand jury recommended that dam and levee owners be required to prepare such emergency plans and submit them each year to the OES/HS; that the OES/HS be given direction and funding to assess the risk the county's dams and levees face and develop emergency response plans; and that county, city and district public works officials and engineers evaluate and report on the integrity of the dams and levees.