§ 24.25.025. Reduced riparian habitat area width.

Except when inconsistent with TCC Section 24.25.030 below, the approval authority, in consultation with the Washington Department of Fish and Wildlife (WDFW) and others with expertise, may reduce the riparian habitat area width specified in Table 24.25-1. Riparian habitat areas may not be reduced for fish bearing streams or marine waters without the approval of a reasonable use exception except as otherwise allowed in this section and Chapter 24.50 TCC. The applicant shall provide the approval authority with sufficient information to enable a determination as to whether the subject area qualifies for a habitat area or buffer reduction under this section. The approval authority may require technical review by a qualified professional, at the applicant's expense, to evaluate and verify the information submitted by the applicant.

A.

Type Np and Ns streams and other streams not listed above. The width of standard riparian habitat areas along Type Np and Ns streams more than one quarter mile upstream from confluence with a Type F or S stream, Puget Sound, a Category I-III wetland (see chapter 24.30 TCC), or a lake or pond protected by this chapter may be reduced up to a total of twenty-five percent for Np streams and fifty percent for Ns streams and other streams not listed above, if:

1.

The land use abutting the riparian habitat area will not generate pollutants or sediment that would reach the stream, elevate water temperature, or increase peak stream flows; and

2.

Best management practices (BMPs) or other mitigation measures will be employed as warranted to protect all of the riparian habitat functions and prevent pollutants and sediment from reaching the stream.

3.

The approval authority determines that the proposed reduction in buffer width, coupled with any the proposed mitigation plan, would result in protection of the stream and stream functions or improved buffer functions than the standard buffer without such enhancement. The approval authority shall make this determination based on the applicant's proposed mitigation plan and a comparative analysis of all stream and buffer functions under existing and enhanced conditions (e.g., filtration of sediments, excess nutrients, and pollutants; flood storage; erosion control; moderation of stormwater impacts; and shading for water temperature moderation) prepared by the applicant, or applicant's consultant if appropriate.

Factors to be considered include, but are not limited to, the surface roughness of the buffer (e.g., the presence of fallen trees and other material that slow the flow of water and increase the buffer's ability to retain sediment and infiltrate stormwater); the composition and density of vegetation; the stream's position in the landscape; slope; and soils. The approval authority may consult with ecology, WDFW or others with expertise as necessary to evaluate the applicant's proposal.

B.

Isolated riparian areas/buffers.

1.

If topographic breaks (e.g., bluffs) or a road (not including logging roads), railroad or other lineal facility or barrier separates and functionally isolates a portion of the riparian habitat area or buffer, the approval authority, in consultation with the WDFW, may reduce the riparian habitat area or buffer width to the minimum extent necessary to exclude the isolated area if:

a.

The barrier occurs naturally or the facility or barrier was legally established prior to July 24, 2013; and

b.

The area proposed to be segregated from the riparian habitat area or buffer does not perform any biological, water quality, or hydrological functions related to the remainder of riparian habitat area, buffer, or adjacent waterbody.

C.

Culvert and pipe removal. Applicants proposing to daylight or open up a stream by removing a pipe or culvert from a stream shall submit a critical area report (see Chapter 24.35 TCC) demonstrating that no net loss of habitat or reduction in water quality would occur as a result of such action, and what buffers are present to protect the stream functions. Water quality protection methods may include, but are not limited to, a combination of a berm and vegetation beside the stream, a stormwater treatment system; or dense, continuous vegetative ground cover at least one hundred feet in width. In order to protect water quality of the stream, a proposed buffer with a slope of five percent or more or has a channelized drainage path that would allow untreated stormwater to enter the stream, the approval authority may require that a device (e.g., a perforated pipe) be installed at the outer edge of the buffer or that the slope be graded to induce sheet flow of stormwater.

D.

When evaluating the proposal, the approval authority shall consider the sensitivity of the stream onsite and downstream, the potential of adjoining uses to contaminate the stream; the ability of the existing and proposed vegetation to filter sediment and pollutants; slope; drainage patterns; the likelihood that proposed water treatment method(s) will be effective in maintaining water quality; and other relevant factors.

(Ord. No. 14773, § 3(Att. B), 7-24-2012; Ord. No. 14961, § 5(Att. E), 12-17-2013)