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Our county’s diverse ecological regions create a range of mosquito sources. The District regularly surveys more than 10,000 acres of marshland along the waterfront, acres of irrigated farmland in the eastern county, and numerous ponds, creeks, and residential sources countywide in an effort to control the species of mosquitoes currently in existence while also on the lookout for the potential arrival of new and invasive mosquito species. The county is also home to many insects that resemble mosquitoes.

Upon request for service, the District will inspect your property for mosquito problems and provide advice on controlling their populations.

With 23 different kinds of mosquitoes that inhabit a variety of water sources, it’s important that the homeowner or caller provide our District employee with a mosquito sample that can be identified to determine its possible source, however, we will still be able to provide service without a one (results may be limited without a sample). Simply swat a mosquito and save it or tape it to a piece of paper for the District employee.

The District also appreciates Contra Costa County residents doing their part to protect public health by reporting non-maintained swimming pools (pools that are not chlorinated or filtered). Residents can submit swimming pool reports anonymously by phone (925) 685-9301 or online.