The key messages are now available for download as a Word file. The information provided in the Word file is also available below. If you have any questions, please contact Nikki Blomquist (Nikki.Blomquist@water.ca.gov) or Jason Ince (Jason.Ince@water.ca.gov).
Preparing for devastating floods is critical for all Californians. Flooding can happen across the state in all regions and any time of year.
California Flood Preparedness Week brings together state, federal and local agencies to inform residents about risks associated with flooding and tools that families can use to prepare for flooding.
In 2023, 31 atmospheric river storms hit California, causing widespread damage from the coast to the Sierra Nevada. Last winter, most of Southern California including Los Angeles, San Diego, and Palm Springs and surrounding communities experienced flooding.
California’s diverse geography contributes to the state’s significant flood risk. Even areas like California’s desert regions, which typically receive little rain during the winter, can experience intense flash flooding.
More than 7 million California residents are at risk of flooding, and many don’t realize it. Flooding can occur throughout the state, from rural communities to urban areas, at the base of hills and along the coast.
In 2023, 47 counties had a storm or flood related state of emergency, impacting nearly every corner of the state. Every county in California has experienced a federally declared flood disaster in the past 20 years. Counties with relatively low risk for a major flood event could be impacted by the results of a catastrophic flood elsewhere in the state, when employment centers, transportation facilities, utilities and the economy are affected.
The impacts of a major flood would be devastating to California and to the nation.
In addition to tragic loss of life, flooding in California can have a serious impact on the state’s economy, and as one of the world’s largest economies in the world, a major flood in California will have an unprecedented impact on the national economy as well.
Climate change is increasing the levels of water vapor in the atmosphere and is making water availability less predictable. This can lead to more intense rainstorms in some areas, while other regions may face more severe drought conditions, especially during the summer months.
It is increasingly clear that climate change has influenced the key water-related variables that contribute to floods, such as rainfall, snowmelt, and the capacity of storms to hold more water.
Worsening floods due to climate change are putting a growing number of communities at risk.
Understanding what causes these natural events and makes them more extreme helps determine what we can do to control or prevent the loss of property or life that comes from natural disasters. By recognizing that climate change is one of the greatest influences on increases to flood risk, you can make informed decisions and potentially change your own habits.
As noted in California’s recently announced Water Supply Strategy, the state has historically swung from drought to flood conditions, and those swings are expected to become more extreme under climate change and increase the likelihood of extreme, large storm and flood events as well as droughts.
After wildfires, there is a significant increase in the risk of flash flooding, mudflows and debris flows to the communities and homes downslope of the burn areas.
After wildfires, when rain falls in the burn areas, the ground cannot absorb the water, so it flows downhill and may pick up topsoil as it goes. On average it takes 2-5 years for the topsoil and vegetation to return to pre-fire conditions.
Debris flows can average 10-15 feet high, be deeper than 35 feet, reach 35 miles per hour and travel miles from where they begin.
Communities and individuals usually have hours or days to prepare for river flooding; however, flash flooding and mud and debris flows happen in a matter of minutes. Early preparation is key.
Because flash flooding and mud and debris flows happen so quickly, it is critical for people and communities living downslope of a burn area to follow three basic steps:
o Be aware of your risk – know whether your home is downslope of a burn area; pay attention to weather forecasts; listen to local authorities.
o Be prepared – always have an emergency evacuation kit ready; be prepared to evacuate early; have a plan for where you will go in an emergency and what to do with your pets.
o Take action – subscribe to your local emergency providers to get updated information. Visit the National Weather Service webpage to get updated weather information for your community. If local authorities issue an evacuation order, do not delay, follow local guidelines for evacuation.
Preparing for a flood should occur well before the rains come. It’s important to know the risk of disasters in your area and check your insurance coverage. Flooding is not covered by most homeowner’s insurance policies, and in most cases, it can take 30 days for a flood insurance policy to take effect. Learn more about your options for flood insurance at www.floodsmart.gov/why-buy-flood-insurance.
Do you know if you live in a Dam Inundation Zone or in an area that is prone to flooding? You can visit DWR’s Flood Risk Notification webpage for resources and information on flood risk areas: www.water.ca.gov/myfloodrisk.
Here are some basic tips for limiting the impacts that flooding can have on you and your family:
Make a plan - Prepare for a flood by protecting your property and moving valuables to higher levels. Your family may not be together if a disaster strikes; choose a family meeting place and a plan for how to communicate during an emergency.
o When choosing a meeting location make sure the location is safe and is easily accessible during an emergency, make sure it is on higher ground and out of the flood zone, if possible.
o If you have pets and animals, you need to plan what you’ll do with them during a flood and ensure your pets’ tags and registrations are up to date so they can be identified.
o It is extremely difficult to see how deep flood water is, so don’t drive through water on the roadway. Just six inches of water will reach the bottom of most passenger cars, causing loss of control and possible stalling. Eighteen inches of water can float an SUV or truck.
o A plan is only effective if your family members are informed about what is in the plan. It is important to hold regular household meetings to review and practice your plan.
Put together an evacuation kit - An evacuation kit is a collection of basic items your household may need in the event of an emergency.
o You never know where you may be when flooding occurs. You may not be able to return home due to road closures and flooding. Maintaining emergency supply kits in your home, vehicle, and at work can provide essential supplies during the initial days following a flood.
o Being prepared means having your own food, water and other supplies to last for several days. A large flood event could impact the availability of drinkable water, so having the ability to purify salt or stagnant water is essential.
o Don’t forget to consider the unique needs each person may have in case you have to evacuate quickly; do you have an adequate supply of medication or access to medical devices?
o It is important to periodically check supplies and refresh water, food, batteries, and first aid items when needed.
Stay informed when a disaster strikes – when emergencies strike, public safety officials use timely and reliable systems to alert you. Make sure you enable Emergency Alert Messages on your cell phone.
o Rely on accurate, official information. Misinformation runs rampant during emergencies. The best place to get accurate, up-to-date information is your local fire, law enforcement, and County Office of Emergency Services.
o Subscribe to the National Weather Services for alerts about extreme weather events and flooding.
o If local authorities issue an evacuation order, do not delay, follow local guidelines for evacuation.
Did you know that the typical homeowner’s insurance policy does not cover flooding? Floodsmart.gov educates property owners about the risks and costs of flooding, ways to prepare for flooding, and what to consider when purchasing flood insurance. Flood maps help identify risk for individual properties and how flood risk changes over time due to weather patterns, land development, and erosion. https://www.floodsmart.gov/
The California Nevada River Forecast Center (CNRFC) provides river and flood forecasts and warnings to protect lives and property. CNRFC uses computer models to translate meteorologic observations into estimates of river flows to help communities and individuals assess their flood risk. A map of weather warnings and advisories makes it easy to find current information on what Californians can do to respond to hazardous weather in their area. https://www.cnrfc.noaa.gov/
The Governor’s Office of Emergency Services created MyHazards to learn about hazards in your area (earthquake, flood, fire, and tsunami) and steps you can take to reduce your risk. Using the MyHazards tool, you may select a location from a map or enter an address, city, and zip code. The map focuses on the location and any hazards identified in the area, and it provides links to resources reduce risk for those hazards. https://myhazards.caloes.ca.gov/
Ready.gov is a one-stop shop for ways you can prepare for more than 25 types of emergencies or natural hazards, including flooding. Need a plan for your household to decide where to shelter, how to communicate, what to take if you need to evacuate, and what goes into a preparedness kit? Ready.gov has this template and so many more. There’s also an app that walks you through how to plan, protect, and recover from a disaster. https://www.ready.gov/floods
CFPW began in 2012 with a single event in Sacramento County.
This is CFPW's 13th year.
CFPW's purpose is to empower local agencies and entities to inform their citizens about flood risk and flood preparedness using best practices for flood risk communication and to coordinate federal and state agency resources to support local communities’ efforts.
CFPW is a California Silver Jackets Team program.