After the 1971 San Fernando earthquake , the California Department of Water Resources Division of Safety of Dams directed a stability investigation of all hydraulic-fill dams in California , including the Chatsworth Reservoir dams . The analysis determined that the Chatsworth dams would have to be completely rebuilt in order to be safe during a major earthquake . In 1972 the reservoir was drained and taken out of service . No schedule for reconstructing the Chatsworth Reservoir has been established
1971 San Fernando earthquake
1971 San Fernando earthquake
Chatsworth Nature Preserve