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From early recorded times mosquitoes have been numerous and unpleasantly obvious in Alameda County. From March to October, successive flights of mosquitoes from the bay marshes to the hills pestered the inhabitants of the county. This condition was not restricted to Alameda County, but was part of a general condition experienced by the people of the entire area bordering the San Francisco, San Pablo, and Suisun Bays.

There were a number of early attempts at organized mosquito control in California. In 1904, mosquito control was funded by the San Rafael Improvement Club for the North Bay marshes and the Burlingame Improvement Club for San Mateo County marshes. In 1910, W.B. Herms and Harold F. Gray organized anti-malaria campaigns which started in Oroville and Bakersfield. Finally, in 1915, the Mosquito Abatement District act was passed by the legislature and the bill was signed by the governor. This bill authorized the formation of mosquito control districts.

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In January of 1926, the campaign to form a mosquito abatement district in Alameda County was launched in response to an article written by Professor W.B. Herms entitled “What Should Be Done in Alameda County Towards Promoting Mosquito Abatement?” Numerous failed attempts were made over the next few years to secure the number of signatures needed to petition the Board of Supervisors. In late 1928 and early 1929, resolutions of endorsement for the formation of the District were passed by the city councils of Berkeley, San Leandro, Hayward, Oakland, Alameda, Piedmont, and Emeryville. By January 28, 1930, more than 32,000 signatures had been collected, nearly three times the minimum legally required number. On March 11, the Board of Supervisors passed the ordinance organizing the District and the certificate of incorporation was filed with the Secretary of the State of California on March 14, 1930.

Early work undertaken by the District focused on ditching in the marshes to promote drainage of salt marsh mosquito breeding sources. As the tremendous hordes of salt marsh mosquitoes were reduced to the point of occasional annoyance, citizens began to take note of the fresh water mosquitoes around their homes and gardens, and demand relief from those mosquitoes as well. The expansion of work necessitated more personnel and more equipment. Therefore, in the late 1930’s and early 1940’s, the District constructed operational depots in Decoto, Hayward, and Oakland. The District operated out of multiple satellite depots until completion of the current Hayward office in 1984.