PROJECT ALERT NOTICE (CA) CAWSC storm response

Date: Fri, 14 Feb 2025 19:56:38 EST

Summary: CAWSC field crews measuring high flows due to ongoing atmospheric river

The second wave of the atmospheric river hit the state late yesterday and into this morning, bringing precipitation to most of the state and concerns about flooding homes and businesses, as well as mudflows and debris flows from burn areas. Many of areas of the state are under flood watches into the weekend.

1 USGS streamgage is above minor flood stage and 5 USGS streamgages are above action stage. 17 crews made up of 25 staff are measuring flood warning streamgages in the areas around Sacramento, San Diego, and Salinas.

Yesterday, a Rapid Deployment Gage (RDG) was installed during continuous rainfall near the outlet of Topanga Creek, the outflow from Topanga Canyon burned by the Palisades Fire in January. The goal is to monitor the high flows, debris flows, and mudslides into at-risk areas and roadways. Shortly after the staff successfully set the gage to record and transmit water level data, they had to leave immediately because authorities were concerned about the high potential for mudflows and slope instability caused by the continuous rainfall. Later that day, mudflows covered sections of the PCH and closed the road. The RDG captured a rapid rise and recession, but the RDG stopped functioning shortly afterward. This section of the PCH remained closed earlier today, and the repair visit is scheduled for early next week.