17.130.060 Standard buffer width requirements – SMP.
Buffers shall be required for all streams regulated by this chapter. Required stream buffer widths are as stated in this section.
(1) Required widths for stream buffers are as follows:
(a) For Type 1 streams – 150 feet;
(b) For Type 2 streams – 150 feet;
(c) For Type 3 streams – 100 feet;
(d) For Type 4 streams – 75 feet; and
(e) For Type 5 streams – 50 feet.
(2) Measurement. The buffer shall be measured horizontally in a landward direction from the ordinary high water mark. Where lands adjacent to a stream display a continuous slope of 25 percent or greater, the buffer shall include all such sloping areas. Where the horizontal distance of the sloping area is greater than the required standard buffer, the buffer shall be extended to a point 25 feet beyond the top of the bank of the sloping area.
(3) Averaging Buffer Widths. The width of a buffer may be averaged, thereby reducing the width of a portion of the buffer and increasing the width of another portion, if all of the following requirements are met:
(a) Averaging will not impair or reduce the habitat, water quality purification and enhancement, stormwater detention, groundwater recharge, shoreline protection and erosion protection, and other functions of the stream or buffer;
(b) The total area of the buffer on the subject property is not less than the buffer which would be required if averaging were not allowed; and
(c) No part of the width of the buffer is less than 65 percent of the required width or 25 feet, whichever is greater.
(4) Buffer Width Reduction. Buffer widths may be reduced if the buffer is enhanced in accordance with the following requirements:
(a) Buffer width reduction and enhancement is targeted for buffer areas that have minimal functional values due to existing physical characteristics;
(b) The applicant demonstrates that proposed buffer enhancement, together with proposed buffer width reduction, will result in an increase in the functional value of the buffer when compared with the functional value of the standard buffer;
(c) The applicant includes a comparative analysis of buffer values prior to and after enhancement, and demonstrates compliance with this section, as part of the critical area report required by SMC 17.130.090;
(d) The buffer width is not reduced below 75 percent of the standard buffer width, or 25 feet, whichever is greater, and the total buffer area reduction is not less than 75 percent of the total buffer area before reduction; and
(e) The functional values of the stream protected by the buffer are not decreased.
(5) Buffer Exclusion. An area within the standard buffers may be excluded if the area is functionally and effectively disconnected from the FWHCA by a paved road, railroad or other substantially developed surface of sufficient width and with use characteristics such that buffer functions are not provided. The equivalent of the area excluded shall be provided elsewhere adjacent to the wetland through buffer averaging provisions not subject to the limit on area or width. Where the entire area excluded cannot feasibly be provided, other mitigation may be approved to provide equivalent function. This provision shall not apply to such a facility within a development proposal or contiguous ownership that can be feasibly relocated to accommodate standard buffers.
(6) Reach Based Alternative Buffer Width Requirements. Within Shoreline Management Act jurisdiction the director may follow the following buffer width requirements without a variance:
Stillaguamish River Reach A from the SR 532 bridge to, but not including, the “Railroad Parcel” shall be subject to standard buffers without modification.
Stillaguamish River Reach B west of Twin City Foods, the buffer shall extend 40 feet from the OHWM.
Stillaguamish River Reach C on the Twin City Foods site, if the site is redeveloped in the future such that building modification or replacement takes place, the buffer shall extend 40 feet from the OHWM.
Stillaguamish River Reach D from Twin City Foods to Irvine Slough, the city owned parcel is subject to a native vegetation buffer over the parcel consistent with its primary function of providing public access.
Stillaguamish River Reach E east of Irvine Slough to the city limits is subject to a buffer extending 40 feet from the OHWM on the Stillaguamish River and 35 feet on Irvine Slough up to 25 percent of the lot area.
Stillaguamish River Reach F consisting of the public sewage treatment facility is not subject to buffers beyond existing vegetation buffers as an essential public facility.
Church Creek Reach A from the city limits to Pioneer Highway is subject to critical area buffer requirements, including both stream and steep slope buffers.
Church Creek Reaches B and C north of Pioneer Highway are subject to critical area buffer requirements, including both stream and steep slope buffers. (Ord. 1373 § 43, 2014; Ord. 1164 § 4, 2004).