California Flooding Toolkit

 

Flooding

Floods are the most common natural disaster in the world. According to the the Public Policy Institute of California, floods are the most common natural disaster the state faces. 1 in 5 residents are at risk of floods! 

There are different types of floods.

  • Fluvial Floods: Also known as river floods, these floods happen when rivers, lakes or streams rise and overflood into the neighboring land. These are mostly to happen during the rainy season or after snow melts.  
  • Pluvial Floods: Pluvial floods are when a flood happens independently from an existing body of water. There are two types of Pluvial Floods. 
    • Flash flooding. Where a flood happens quickly from a large amount of rainfall over a short amount of time. 
    • Surface water floods. Where flooding happens when a drainage system or a sewage system gets overwhelmed. 
  • Coastal Flooding: Coastal flooding occurs from high tides, storm surges from tropical storms or hurricanes, or tsunami’s

Flood Facts

  • FEMA has a floodmap for the United States where you can enter an address and see how at risk you are of flooding.  
  • Floods cost on average between $6 Billion -$10 Billion per year in damage. 
  • Anyone who lives in a 100 year flood zone has a 1 in 4 chance of being flooded, this is a higher probability than fire damage. 

Climate Mitigation and Adaptation Solutions 

Climate Mitigation Solutions for Floods

  • Protecting Wetlands. Wetlands are nature’s sponges, and they help absorb flood waters as they happen and prevent them from doing more damage. According to American Rivers, “A single acre of wetland, saturated to a depth of one foot, will retain 330,000 gallons of water – enough to flood thirteen average-sized homes thigh-deep” 
  • Boosting biodiversity. Native plants often tend to have deep roots that create healthy soil and allow for water to seep in more deeply compared to areas that have grass or other non-native plants with short roots. When soil becomes unhealthy it becomes compact and hard and does not allow water to soak into the ground through which means when water sits on top of the soil, it turns to flood water pretty quickly 
  • Permeable Pavements. Cement and Asphalt do not allow water to quickly seep through, urban and flash floods often are a result of water being unable to seep into the earth. Having Permeable pavement solves this problem!
  • Building rain retention solutions into urban areas such as ponds, rain gardens, and bioswales so that water has somewhere to be held during surges. 

Climate Adaptation Solutions for Floods

Download our California Wildfire Toolkit below