Ventura County, one of 58 counties in the State of California, is located on southern California’s Pacific coast, just northwest of Los Angeles. Ventura County is bordered by Los Angeles County to the south and east, Kern County to the north, and Santa Barbara County to the northwest. The county has a population of over 750,000 and consists of 10 incorporated cities which include: Camarillo, Fillmore, Moorpark, Ojai, Oxnard, Port Hueneme, San Buenaventura (Ventura), Santa Paula, Simi Valley, and Thousand Oaks. The county’s unincorporated communities, which make up almost 10 percent of the county’s population, include Bell Canyon, Casitas Springs, Del Norte, El Rio, Hollywood Beach, La Concha, Lake Sherwood, Lockwood Valley, Meiners Oaks, Mira Monte, Montalvo, Newbury Park, Nyeland Acres, Oak Park, Oakview, Piru, Saticoy, and Silver Strand. Anacapa Island of the Channel Islands National Park and San Nicholas Island are located within the jurisdiction of Ventura County. The City of Ventura is the county seat.

The Ventura County Flood Control District was formed on September 12, 1944, by an act of the California State Legislature. The District was formed, in part, to provide for the control and conservation of flood and storm waters and for the protection of watercourses, watersheds, public highways, life, and property from damage or destruction from these waters. The legislation was amended in 1972 to provide for the recreational use and beautification of lands and properties in connection with flood control activities. The legislation was once again amended in 2002 to reflect a change in name from the Ventura County Flood Control District to the Ventura County Watershed Protection District.

The District is funded through property taxes, benefit assessments, and land development fees paid by property owners within the county. The District is a separate legal entity from the Ventura County, but shares the same board members with the county.

To facilitate management of its revenues and projects, the District was divided into four zones, roughly corresponding to the major watersheds within the county. Monies raised within a zone support District studies and projects in that zone. Zone 1 essentially follows the boundaries of the Ventura River Watershed and coastal drainages in the western part of the county. Zone 2 essentially follows the boundaries of the Santa Clara River Watershed and local coastal drainages in the cities of Ventura and Oxnard. Zone 3 essentially follows the boundaries of the Calleguas Creek Watershed and its tributaries. Zone 4 is a mixture of Malibu coastal drainages in the southern part of the county and the relatively undeveloped Cuyama River Watershed in the northern part of the county.

The District possesses jurisdictional authority over any channel containing runoff with a peak flow rate of more than 500 cubic feet per second (cfs) during a 100-year storm. Laterals and side drains contributing runoff to the jurisdictional channels (referred to as "redline" channels) are under the jurisdiction of the state or appropriate local agency. However, lateral and side drain connections to jurisdictional channels must obtain an encroachment permit from the District and provide sufficient information and engineering studies to show that the connection does not negatively impact the conveyance capacity of the jurisdictional channel.

To solve existing flooding problems, the District has developed an Integrated Watershed Protection Plan encompassing all four major watersheds. The Ventura River Watershed was studied as part of the Matilija Dam Ecosystem Restoration Project, a joint effort between the District, the State, and the U.S. Army Corps of Engineers. This project examined the water resource and environmental effects of the removal of Matilija Dam, given that accumulated sediment has compromised the dam’s original functions as a flood control and water supply reservoir. The Santa Clara River Watershed Feasibility Study was a partnership between the Los Angeles County Department of Public Works, the District, and the U.S. Army Corps of Engineers.