(1) All improvements to real and personal property that benefit fish and wildlife habitat, water quality, or water quantity are exempt from taxation if the improvements are included under a written conservation plan approved by a conservation district. The conservation districts must cooperate with the federal natural resource conservation service, other conservation districts, the department of ecology, the department of fish and wildlife, and nonprofit organizations to assist landowners by working with them to obtain approved conservation plans so as to qualify for the exemption provided for in this section. As provided in subsection (3) of this section and RCW
89.08.440(2), a conservation district must initially certify that the best management practice benefits fish and wildlife habitat, water quality, or water quantity. A habitat conservation plan under the terms of the federal endangered species act is not considered a conservation plan for purposes of this exemption.
(2) The exemption remains in effect only if improvements identified in the written best management practices agreement are maintained as originally approved or amended. Improvements made as a requirement to mitigate for impacts to fish and wildlife habitat, water quality, or water quantity are not eligible for exemption under this section.
(3) A claim for exemption under this section must be filed annually with the county assessor on or before October 31st during the year for exemption from taxes levied for collection in the following year when submitted on forms prescribed by the department of revenue developed in consultation with the conservation district. The landowner must certify each subsequent year that the improvements for which exemption is sought are maintained as originally approved or amended in the written conservation plan. In the first filing year, the claim must contain the initial certification by the conservation district that the improvements for which exemption is sought were included under a written conservation plan approved by the conservation district including best management practices that benefit fish and wildlife habitat, water quality, or water quantity. Each subsequent filing year, the claim must contain a copy of the conservation district's initial certification made in the first filing year, along with the landowner's own certification for the current filing year.