Flood Warning and Safety

SMC Alert

The Area Office of Emergency Service (OES) coordinates countywide preparedness, response and protection services and activities for large-scale incidents and disasters.

OES is responsible for alerting and notifying appropriate agencies within the County's 20 cities when disaster strikes; coordinating all agencies that respond; ensuring resources are available and mobilized in times of disaster; developing plans and procedures in response to and recovery from disasters; and developing and providing preparedness materials for our residents.

San Mateo County’s Community Alert System SMC Alert, expands and enhances the County’s ability to provide rapid notice to responders and the public regarding emergencies via SMS/Text messaging and email.  Sign up with SMC Alert.  Additionally, San Mateo County Public Works, Roads Services has an emergency line (24 hours) a day 650/363-4100.


During times of flooding, homes that have not been retrofitted can be protected during emergencies by the installation of sandbags.  For further information about sandbags and the locations of sites where sandbags are available during flooding, contact the County’s Department of Public Works at 650/363-4100.  Pick-up stations are listed below.

County residents in unincorporated areas may pick up sandbags free of charge at the following locations.  There is a limit of 15 bags; requests for additional bags will be considered on a case-by-case basis.  When you are done with them, feel free to bring them back to the yard for disposal or simply empty the sand on your lawn and throw the bags away.


  • Grant Corporation Yard, 752 Chestnut, Redwood City - 650/363-4103
  • Princeton Corporation Yard, 203 Cornell Avenue - 650/728-7993
  • Pescadero Corporation Yard, 1000 Pescadero Road - 650/879-0202
  • Pescadero High School, 350 Butano Cutoff Road
  • La Honda Corporation Yard, 59 Entrada Way - 650/747-0341

In case of an emergency, call 911.

Safety Tips

Following is a list of important considerations that should be followed during times of flooding:

Prepare an evacuation plan. Before the floodwaters hit, develop an evacuation plan among all members of a household that includes a meeting place outside of the house, as well as an escape route out of the floodplain and away from floodwaters.

Do not walk through flowing water. Drowning is the number one cause of flood deaths, mostly during flash floods.  Currents can be deceptive; six inches of moving water can knock you off your feet.  If you walk in standing water, use a pole or stick to ensure that the ground is still there.

Do not drive through a flooded area. More people drown in their cars than anywhere else.  Do not drive around road barriers; the road or bridge may be washed out.

Stay away from power lines and electrical wires. The number two flood-killer after drowning is electrocution.  Electrical current can travel through water.  Report downed power lines to the Portland General Electric or the County Emergency Management Office.

Shut off gas and electricity and move valuable contents upstairs. Be prepared in advance with a detailed checklist because warning of an impending flood may provide little time for preparation prior to evacuation.

Look out for animals, especially snakes. Small animals that have been flooded out of their homes may seek shelter in yours.  Use a pole or stick to poke and turn things over and scare away small animals.

Look before you step. After a flood, the ground and floors are covered with debris including broken bottles and nails.  Floors and stairs that have been covered with mud can be very slippery.

Be alert for gas leaks. Use a flashlight to inspect for damage.  Do not smoke or use candles, lanterns or open flames unless you know that the gas has been turned off and the area has been ventilated.

For more information regarding emergency preparedness, go to http://www.ready.gov/be-informed

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