PG&E recommends that those who evacuate their homes due to flooding should shut off their gas and electricity if they know how and can do so safely. This may prevent gas and electric appliance controls and equipment from being damaged.
If unable to shut off gas to appliance, turn off gas at gas service shutoff valve normally located near the gas meter.
Electricity
Turn off the electric supply to the entire premises at the main electric switch. Warning: Never touch the electric switch or circuit breaker with wet hands or while standing in water.