§ 24.30.070. Wetland mitigation.

All unavoidable adverse impacts to wetlands and associated buffers shall be mitigated consistent with the provisions of this section. A qualified wetland scientist shall identify the wetland functions using the best professional judgment and the best available technology, consistent with guidance from the department of ecology, including but not limited to the following documents: Wetland Rating System for Western Washington; Wetland Mitigation in Washington State, Parts 1 and 2; and Selecting Wetland Mitigation Sites Using a Watershed Approach.

A.

Equivalent or Improved Wetland Functions. Mitigation shall achieve equivalent or improved wetland and buffer functions. The applicant's qualified wetland scientist shall demonstrate that the proposed mitigation will provide functions that are at least equal to the lost or diminished wetland and buffer functions or explain the reasons why that level of mitigation cannot be attained (e.g., it may not be possible to mitigate unavoidable impacts to a bog).

B.

Location of Mitigation. Mitigation shall be on-site unless the approval authority, in consultation with Ecology, determines that paragraphs (1)—(5) below apply. In that case, mitigation may be allowed off-site within the subwatershed of the impacted site. When considering off-site mitigation, preference should be given to using alternative mitigation, such as a mitigation bank, an in-lieu fee program, or advanced mitigation.

1.

There are no mitigation opportunities available on-site due to physical constraints such as hydrology, soils, the size of the property, the location of existing development, the presence of noxious weeds or invasive plants; potential adverse impacts from surrounding land uses; or other factors; or

2.

On-site mitigation would require elimination of high quality upland habitat; or

3.

Off-site mitigation has a greater likelihood of providing equal or improved wetland and buffer functions than mitigation of the impacted wetland and buffer; or

4.

The hydrology and ecosystem of the impacted site will not be substantially damaged by the proposed wetland and/or buffer impacts; or

5.

County-adopted goals or policies for flood storage, flood conveyance, habitat or other wetland functions justify location of the mitigation measures at another site.

C.

Mitigation In-kind. Mitigation for impacts to estuarine wetlands, coastal lagoons and associated buffers shall be as determined to be appropriate by the approval authority in consultation with the WDFW and Ecology. Mitigation for all other lost or diminished wetland and buffer functions shall be in-kind, unless the applicant demonstrates that:

1.

Higher levels of wetland and buffer functions would result from an alternate approach; or

2.

The impacted wetland and buffer provide minimal functions (e.g., they score less than five points for habitat and less than five points for water quality under Ecology's Wetland Rating System for Western Washington) and the proposed mitigation action(s) will result in a wetland with greater functions or provide functions shown to be limiting within a watershed; or

3.

Physical constraints make in-kind mitigation impossible; or

4.

Out-of-kind replacement will best meet the county's adopted goals or policies for the watershed; or

5.

The impacted wetland cannot be mitigated in-kind, based on best available science.

D.

Wetland Mitigation Timing. Where feasible, mitigation projects shall be completed prior to the related wetland alteration or immediately following temporary disturbance of a wetland or buffer. The approval authority may allow the required mitigation to begin up to one year following occupancy of the associated project or commencement of the permitted activity if the applicant's qualified wetland scientist demonstrates to the approval authority's satisfaction that the delay is warranted and will not create environmental degradation or be injurious to the public health, safety, or welfare. Reasons for the requested delay could include, but are not limited to, environmental conditions that could cause project failure, "work windows" specified by the WDFW to avoid fish or wildlife impacts, or seasonal planting or grading constraints. The applicant shall submit a surety consistent with Chapter 24.70 TCC to ensure the completion and success of the required mitigation.

E.

Protection of the Mitigation Site. The area where the mitigation occurred and any associated buffer shall be located in a critical area tract or a conservation easement consistent with Chapter 24.65 TCC.

F.

Mitigation for Illegal Alterations. See Title 26, Code Enforcement.

(Ord. No. 14773, § 3(Att. B), 7-24-2012; Ord. No. 15274, § 2(Att. B)JJJ, 2-23-2016; Ord. No. 15291, § 1(Att. A), 5-10-2016)