In April 2024, Lake Casitas reached elevation 567.00’ (which is the elevation of the spillway) and water began trickling down the dam spillway. The Casitas Dam spillway has operated nine times since its construction, including in 2024. The first spill event occurred in 1978, and the largest occurred in 1998 with a 35,000 AF spill. 

The purpose of the spillway is to prevent overtopping of Casitas Dam. Overtopping could result in significant erosion of the face of the dam affecting its stability. For this reason, water passing through the spillway provides an important safety feature.  Water passing through the spillway is not directly controlled by Casitas operators, but as the water elevation increases over the spillway crest, more water is passed downstream into Coyote Creek.

As Casitas Dam approaches a spill condition, Casitas staff communicates with Ventura County about potential flows in downstream Coyote Creek. Ventura County is the agency responsible for determining if any actions are necessary to prepare for the potential flows in Coyote Creek. For information about emergencies, refer to the Ventura County website: vcemergency.com

The amount of inflow coming into the lake is controlled by Casitas by ramping down operations at the Robles Diversion Facility, the water supply facility bringing water from the Ventura River into Lake Casitas.  Under standard operating protocols, diversions to Lake Casitas cease when the lake level reaches the spillway elevation of 567.00 feet.  After diversions have ceased, natural inflows into the lake may cause further spilling and this is a normal part of the operation of Casitas Dam.  In 2024, the spill rates fluctuated due to weather factors such as precipitation and evaporation, wave action, and customer demands on the Lake Casitas drinking water system.

In the coming weeks, diversions at the Robles Diversion Facility may recommence at a rate targeted to maximize the lake level before the end of the diversion season.

Please be aware that Casitas Dam is a protected critical water facility, and aerial equipment such as drones are prohibited at Casitas Dam and associated federal properties without prior permission.

Lake Casitas Volume and Level

For the most current information regarding Lake Casitas' level and volume, please check the Ventura County Watershed Protection District's site:  https://www.vcwatershed.net/fws/reports/reservoir-report

Lake Casitas Above Sea Level Measurement: https://vcwatershed.net/fws/VCAHPS/php/ahps_d3.htm?gage=691

Lake level and volume data is also available to view along with the Daily Robles Diversion Measurements located on the Learn about Diversions page here: https://www.casitaswater.org/learn-about-diversions