Historic Mosquito ControlIn 1957, the Washington State legislature passed Revised Code of Washington (RCW) 17.28 – Mosquito Control Districts. This legislation allows for the creation of Mosquito Control Districts and provides guidance and authorities associated with the operation of a District. The primary reason that a Mosquito Control District is formed is for the welfare of the public.

Benton County Mosquito Control District #1 was formed in 1957, but funding and operations did not begin until 1969/1970. The formation of this District was brought about due to a concern for repeated epidemics of encephalitis like those seen in the 1940s and to a lesser extent, the 1950s.

Benton County is listed as having 22 different mosquito species and Yakima County has 36 different species (provided by WA Dept of Health). The District has physically trapped 16 different species of mosquitoes. Some of these species are vectors (an organism that can transmit pathogens) for diseases, like West Nile virus (WNv), St. Louis Encephalitis (SLE) and Western Equine Encephalitis (WEE).

Originally, Benton County MCD consisted of the city of West Richland and county lands surrounding the areas of Benton City, Kennewick and Richland. The city of Richland was annexed into the District in 1970. The cities of Prosser and Benton City were annexed in 1971. In 1990 areas of the city of Kennewick that were not within the District were annexed. The District expanded even more in 1992 with the annexation of Grandview and Mabton.

We are governed by a Board of Trustees that is comprised of appointed representatives from each of the cities and county commissioner districts within the District. This works out to 7 city representatives and 5 county commissioner representatives; 3 for Benton County and 2 for Yakima County.

Funding is generated by a special tax that is levied against property within the District. For the year 2014, it works out to approximately 9.6 cents per $1,000 of property value in Benton County. This is computed by the county assessor and then billed and collected by the county treasurer.

In Yakima County, the assessment is $6.60 per acre plus a $1.50 fee that is charged by the county Assessor and Treasurer to administer the benefit assessment.