Provides that a county, city, town, water-sewer district, or flood control zone district must: consider, and to the extent possible consistent with the Department of Ecology's design guidelines for stormwater retention ponds, construct stormwater facilities to maintain and control vegetation to inhibit mosquito breeding; and consult with local mosquito control districts, where established, when developing construction plans that include stormwater retention ponds. A county, city, town, water-sewer district, or flood control zone district must maintain and control vegetation growth in, without compromising the function of, stormwater retention ponds to minimize mosquito propagation. When notified of the presence of WNV or other mosquito-borne human diseases, a county, city, town, water-sewer district, or flood control zone district must consult with DOH or the mosquito control district as to the most effective IPM strategy to use. In areas with mosquito control districts, the district must abate mosquitoes when notified of the presence of WNV or other mosquito-borne human diseases.