Understanding Flood Alerts

There are times when a flood emergency happens unexpectedly. Often, however, there is an increasing threat that is known in advance.

Typically, there are three notification stages for increasing threat levels:

  • Evacuation or protection alert – caution should be taken. At this stage, consider packing important items such as documents, food, and water for all members of the household as well as pets (see the sidebar for a link about emergency kits).
  • Evacuation warning or notice – threat is increasing. At this stage, voluntary evacuation is suggested especially for those who are elderly or disabled.
  • Evacuation request or order – threat is high or an emergency event is in progress. At this stage, an evacuation is required. You can be expected to be alerted through various media such as radio, TV, social media, and electronic highway signs.

All five Delta counties (Conta Costa, Sacramento, San Joaquin, Solano, and Yolo) have an emergency alert system you can sign up for to receive direct communications via calls, texts, and/or emails. In case there is no signal or your phone is not charged, the best way to receive information is through radio. A hand-crank radio is an important item to add to your emergency kit to receive information should electricity also be down or unavailable.

Other flood warning language:

Flood Watch means it is possible that flooding will occur in a specified area. Be alert and prepared for a flood emergency.

Flood Warning means flooding is occurring or is imminent in a specified area. Move to safe ground immediately.

Flash Flood Warning means sudden and violent flood is occurring or is imminent in a specified area. Take immediate precautions to protect life and property

Visit the Evacuation Plans webpage for more information.

Visit your county resource page for flood alert system information:

Download other emergency information apps to your smart device: