Ready Riverside


In Riverside flooding can happen anytime, but October to April are our rainiest months. When there's a flood risk, the National Weather Service issues alerts. Sign up to receive emergency alerts.

Download our Flash Flood Preparedness Sheet here

Sandbag Locations




Facts about Flash Flooding

  • A Flood is an overflow of water that submerges land that is usually dry. Flash Flooding is a rapid flooding of low-lying areas. Flash floods are distinguished from regular flooding by having a timescale of less than 6 hours between precipitation or release of water and the onset of flooding.
  • Flash flooding can occur miles downstream from areas of heavy precipitation.
  • Flash flooding can occur on days with no precipitation too! Meltwater from snow and glaciers and scheduled dam releases can lead to flash flooding, and a dam failure led to the deadliest flash flood in US History, destroying the town of Johnstown, PA.


Be Prepared

  • Check the weather regularly and know what it means. The National Weather Service San Diego Office is responsible for our area.
  • A Flash Flood Watch means conditions are favorable for flash flooding. A Flash Flood Warning means a flash flood is imminent or occurring in the warned area. In rare circumstances, some National Weather Service offices can enhance the language in a warning to warn of a Flash Flood Emergency, indicating a severe flooding situation in densely populated areas.
  • Understand your flood risk. Climate and topography make flooding a reality in Riverside. And certain parts of the city are more likely to flood. Learn about your flood risk with the FEMA Flood Map Service Center


Insure your property

Floods are the most common and costly natural disaster, so it’s important to have the right coverage. Homeowners and renters insurance usually don’t cover flood damage. Flood insurance takes 30 days to take effect, so now’s the time to buy.


Clean your property and street

  • Remove debris from gutters and downspouts.
  • Clear debris from catch basins and drains. Report clogged catch basins to 311. Check out our adopt-a-drain!
  • Prune trees and shrubs.
  • Bring outdoor furniture and decorations inside.
  • Secure or bring garbage bins inside.
  • Move possessions to your highest floor.
  • Photograph your property for insurance purposes.



  • Water depth can be difficult to judge, especially at night, and you may not see a road that is washed out too! Remember: Turn Around, Don’t Drown.


Outdoor Activities

  • Before going out to hike, bike, or another outdoor activity, check the weather forecast and information about the area. Is it prone to flash floods?
  • Have a back-up plan. After planning and travelling to your destination, it can be hard to decide to cancel your activity. If you have a back-up plan in an area that is known to be safer, you’re less likely to put yourself in a dangerous situation.
  • Watch for suddenly darkening skies or listen for thunder. Move to your back-up plan if these conditions start to develop.
  • Remember that flash floods can occur suddenly, and miles from the source of water. You may not be able to hear or see a storm that can cause a flash flood.


Have an escape plan and be prepared to ride it out, even by climbing a tree or other sturdy object. Some floods can take hours to recede, but even getting behind a jutting piece of canyon wall could protect you from the powerful waterflow.


During a flood

Avoid flood waters

  • Move to higher ground.
  • Don’t walk or drive through flood waters. 
  • If water rises around your car, abandon the car immediately.

Report flooding

  • Call 911 to report street flooding and life-threatening emergencies.

Avoid contact with electricity

  • Don’t touch electrical equipment. Every source of electricity can be dangerous during or after a flood.


After a flood

  • Don't return home until authorities say it is safe.
  • Be aware of areas where floodwaters have receded and watch out for debris. Floodwaters can erode roads and walkways.
  • Stay away from standing water. It might be electrically charged from underground or downed power lines.
  • Photograph damage to your property for insurance purposes.


Build to avoid flood damage