(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. The six key points to remember are to:
1. Know Your Flood Hazard
2. Insure Your Property
3. Protect People from the Hazard
4. Protect Your Community from the Hazard
5. Build Responsibly
6. Protect Natural Floodplain Functions
Know Your Flood Hazard
If your property is subject to flooding, FEMA has created flood hazard maps to show different degrees of risk of flooding by outlining different flood risk areas. Visit the FEMA Map Service Center to find flood hazard information; you can enter your address directly.
Public Works staff can determine your flood zone determination 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.
See below for additional information on knowing your flood risk:
- Department of Water Resources 2020 Flood Risk Notification
- National Flood Insurance Program (NFIP) "Know Your Risk (PDF)"
- FEMA - Know Your Risk: By Audience
- County Flood Zone Determination Form (PDF)
Insure Your Property
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:
- National Flood Insurance Program (NFIP)
- Top 10 Facts Every Consumer Needs to Know about the NFIP (PDF)
- Your Homeowners' Insurance Doesn’t Cover Floods (PDF)
- Why Do I Need Flood Insurance? (PDF) (Spanish) (PDF)
- Flood Insurance Requirements for Recipients of Federal Disaster Assistance (PDF)
- WYO (Write Your Own) Flood Insurance Company List
- Preferred Risk Policy (PDF) (Spanish) (PDF)
- Flood Insurance Claims Handbook (PDF) (Spanish) (PDF)
- Increased Cost of Compliance Coverage (PDF) (Spanish) (PDF)
For Real Estate Professionals/Insurance Agents:
- Top 10 Facts Every Agent Needs to Know about the NFIP (PDF)
- Questions & Answers about Flood Insurance for Real Estate Professionals (PDF)
Protect People from the Hazard
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.
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:
- Ready.gov: Prepare for a Flood
- Be Prepared for a Flood (PDF)
- Know Your Alerts and Warnings (PDF)
- Make a Plan for Disasters
- Create Your Family Emergency Communication Plan (PDF) (Spanish) (PDF)
- Preparation for Individuals with Disabilities and Other Needs
- Preparation for Seniors
- Preparation for Your Pets
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.
See below for additional information on ways to protect your property:
- Safeguard Critical Documents and Valuables (Spanish) (PDF)
- Protect Your Home from Flooding - Low-Cost Projects You Can Do Yourself (PDF)
- Homeowner’s Guide to Retrofitting: Six Ways to Protect Your Home from Flooding (PDF)
- Protecting Building Utilities from Flood Damage (PDF)
- Reducing Flood Risk to Residential Buildings that Cannot Be Elevated (PDF)
- Wet Floodproofing Requirements for Structures Located in Special Flood Hazard Areas (SFHA's) (PDF)
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:
- Engineering Principles and Practices for Retrofitting Flood-Prone Residential Structures (Third Edition) (PDF)
- FEMA: Above the Flood: Elevating Your Floodprone House (PDF)
- FEMA: Build Back Safer and Stronger (PDF)
- FEMA: Flood Damage-Resistant Materials Requirements (PDF)
- FEMA: Requirements for Flood Openings in Foundation Walls and Walls of Enclosures (PDF)
- Contra Costa Clean Water Program - Stormwater C.3 Guidebook and Stormwater Control Plan Template
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).
- FEMA: Floodplain Natural Resources and Functions (PDF)
- The Natural and Beneficial Functions of Floodplains (PDF)
- County Watershed Program - Public Education Outreach
- County Watershed Forum Website