San Mateo County is telling residents to prepare for flooding before the first major storm of what federal forecasters say could be a historic El Niño season.
The county posted the preparedness message Wednesday, Oct. 7, on its X account, urging residents to take four steps: make a plan, build an emergency kit, pick up sandbags and sign up for SMC Alert. The post linked to the county's winter weather preparedness page, which lists local sandbag sites and flood safety guidance.
NOAA's Climate Prediction Center issued an El Niño Advisory on Sept. 10, stating the event is strengthening with a greater than 90% chance of reaching "very strong" status this fall and winter. The agency put the odds of a historic event exceeding every El Niño since 1950 at 75% during October–December 2026. Those probabilities describe El Niño’s strength, not the likelihood of flooding in a particular community.
Gov. Gavin Newsom proclaimed a state of emergency Sept. 21 to speed up flood preparations statewide, according to the governor’s announcement. The proclamation allows California to mobilize resources, streamline procurement and stage flood-fighting supplies before severe weather arrives.
The governor’s announcement cautions that El Niño does not guarantee a wet winter or any particular storm.
Where to get sandbags
The county's preparedness page lists two locations for Burlingame and Hillsborough residents:
- Burlingame: 600 California Dr. at Floribunda Ave. (vacant lot)
- Hillsborough: Hillsborough Town Hall, 1600 Floribunda Ave. (Walnut parking lot)
Burlingame’s city FAQ says residents fill their own bags at the self-service station. Shovels are provided, and the limit is 15 bags per property address.
Local flood exposure
Burlingame's Bayfront corridor sits in a low-lying area between Highway 101 and San Francisco Bay, exposed to flood risks. Existing riprap floodwalls provide only minimal protection, according to a 2022 description by the San Mateo County Flood and Sea Level Rise Resiliency District, known as OneShoreline.
Sign up for SMC Alert
SMC Alert is the county's free emergency notification system. It sends text, voice and email messages for floods, fires, severe weather, tsunamis, evacuation routes and shelter locations.
The service is opt-in, so residents must register. The county recommends adding addresses, such as home or work, to help target alerts to relevant locations.
The county's preparedness page notes that six inches of moving water can knock a person down and one foot of moving water can sweep a vehicle away. Residents should not walk or drive through floodwater.
