Flood Preparedness

(Alhambra Creek Flooding, 1950-1951)

According to the California Department of Water Resources, catastrophic flooding can happen even in the middle of a drought, so we must "be aware, be prepared, and take action!"

Prepare your family and property for flooding by learning about what to do before, during, and after a flood.

Be aware of your risk.

Be aware of your risk: Know whether your home is in a flood zone ; pay attention to weather forecasts; and listen to local authorities.

FEMA: Flood Risk Basics and Communities -- a Customer Experience Toolkit Video

Public Works staff can determine your flood zone using available Assessor’s Parcel Map, County base maps, FEMA information, and other documents or maps. The fee for this written determination is $50 per parcel. If a site visit is warranted, there will be an additional $250 fee.

While the below link is targeted toward east county communities, there is a lot of good information relative to flood preparedness and responsibilities that apply to all.

Stormwater Drainage & Flooding

See below for additional information on knowing your flood risk:

Department of Water Resources 2022 Flood Risk Notification
FEMA - Know Your Risk: By Audience
County Flood Zone Determination Form (PDF)

Stay Out, Stay Alive!
Flood control channels are part of our community’s infrastructure. They are designed to drain stormwater from our communities swiftly to prevent flooding, and should not be used for recreation. Be aware of fast-moving stormwaters in our channels and creeks.

Visit the Contra Costa County Flood Control and Water Conservation District’s webpage on the Creek and Channel Safety Awareness Program for additional information.

Be Prepared.

Be prepared: Always have an emergency evacuation kit ready; be prepared to evacuate early; have a household inventory with copies of critical documents; and have a plan for where you will go in an emergency and what to do with your pets.

California Department of Water Resources - Being Prepared at Home

California Department of Water Resources - Being Prepared on the Road

Know Your Flood Warning Signs
If flooding occurs, the County will warn residents through radio, TV announcements, and emergency officials and vehicles. Please know the flood warning procedures and plan escapes to higher ground.

The Office of Emergency Services has useful information, such as the Local Multi-Jurisdictional Local Hazard Mitigation Plan, Emergency Operations Plan, and Community Warning System.

See below for additional information on protecting yourself and your family from flood hazards:

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Protect Your Property
Along with preparing yourself and your family for a flood, safeguard your property (e.g., home, business, and possessions). Keep debris and trash out of streams, ditches, and drain inlets. These convey stormwater from our community to the bay, delta, and sea. There are flood-proofing improvements that can be done to your structure that may reduce damage caused by flooding. Consider elevating the building using flood-resistant materials, or performing simpler improvements, such as replacing your flooded furnace with one elevated above the flood level.

Sandbag Station Locations and Use

See below for additional information on ways to protect your property:

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Take Action.

Take action: Evacuate immediately when advised to. Also, homeowners' insurance does not cover damage due to flooding; consider purchasing flood insurance.

Build Responsibly
Get a building permit from our Application and Permit Center before your build. A Floodplain Permit is required if you are constructing within a FEMA-designated Special Flood Hazard Area (SFHA). Improvements within the floodplain have the potential to impact flood levels, your property, and your structure.

For new developments and redevelopments, Provision C.3 in the Municipal Regional Permit (MRP) requires site designs to minimize impervious surface areas and encourage the use of pervious surfaces, where feasible, to infiltrate the underlying soil. Runoff from impervious surface areas must be captured and treated before discharging. The Stormwater C.3 Guidebook assists applicants through the process of submittal and review. Visit the County Watershed Program and the Contra Costa County Clean Water websites for additional information.

See below for additional information on building responsibly:

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Protect Natural Floodplain Functions
Don’t dump in the storm drains; they drain to our bay or delta. Ensure that RAIN GOES DOWN the DRAIN.

The storm drain inlets do not route water to a treatment facility. Stormwater flow untreated to the bay or delta. If you need to place storm drain markers on your drain inlet to remind people of this fact, makers are sold at the Public Works Department located at 255 Glacier Drive in Martinez.

Visit or contact our County Watershed Program for more information on compliance with our National Pollutant Discharge Elimination System (NPDES) Municipal Regional Permit (MRP).

Natural floodplains are resources that may contain rare and endangered plants and animals, and they are of historical significance, as well. See below for additional information on natural floodplains and our watershed (County’s public education and outreach information).

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Insure Your Property

FEMA: What do I need to know about flood insurance coverage?

Your standard homeowners’ insurance does not cover flood damage. You can lessen the financial consequences of a flood by obtaining flood insurance. Find an insurance agent near you through FloodSmart.gov (National Flood Insurance Program).

See below for additional information on flood insurance:

For Real Estate Professionals/Insurance Agents:

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