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SO-180: Description

Summary

A wetland management area special overlay district provides a means to designate certain unique and outstanding wetlands when necessary to protect their functions and values from the impacts created from geographic and hydrologic isolation and impervious surface.

Story

Amended by Ord. 12823, 08/18/1997 (Language)
Amended by Ord. 12824, 08/18/1997 (Map)
Amended by Ord. 13232, 07/09/1998 (Map)
Amended by Ord. 13307, 11/06/1998 (Language)
Amended by Ord. 17485, 12/03/2012 (Map)

Description

Wetland Management Area SDO

Development Condition Text

21A.38.120 Special district overlay - Wetland management areas .

A. The purpose of the wetland management area special overlay district is to provide a means to designate certain unique and outstanding wetlands when necessary to protect their functions and values from the impacts created from geographic and hydrologic isolation and impervious surface.

B. The following development standards shall be applied in addition to all applicable requirements of K.C.C. chapter 21A.24 to development proposals located within a wetland management area district overlay:

1. All subdivisions and short subdivisions on residentially zoned properties that are identified in an adopted basin plan for impervious surface limitations, shall have a maximum impervious surface area of eight percent of the gross acreage of the plat. For areas that are not covered by an adopted basin plan, this limit shall apply to all residentially zoned lands located within the wetland management area. Distribution of the allowable impervious area among the platted lots shall be recorded on the face of the plat. Impervious surface of existing roads need not be counted towards the allowable impervious area. This condition may be modified by the director for the minimum necessary to accommodate unusual site access conditions;

2. All subdivisions and short subdivisions on properties identified in an adopted basin plan for clustering and setaside requirements shall be required to cluster away from wetlands or the axis of corridors along stream tributaries and identified swales connecting wetlands in order to minimize land disturbance and maximize distance from these sensitive features. At least sixty-five percent of affected portions of RA-zoned properties and at least fifty percent of all other affected portions of the property shall be left in native vegetation, preferably forest, and placed in a permanent open space tract. In the absence of a basin plan, these requirements shall apply to all lands containing or adjacent to a wetland, a stream tributary corridor or a swale connecting wetlands; and

3. Clearing and grading activity from October 1 through March 31 shall meet the provisions of K.C.C. 16.82.150D wherever not already applicable. (Ord. 13307 § 1, 1998: Ord. 12823 § 14, 1997: Ord. 12809 § 5, 1997).

Ordinance

12809

Effective Date

August 10, 1997

Changes

Amended by Ord. 12823, 08/18/1997 (Language)
Amended by Ord. 12824, 08/18/1997 (Map)
Amended by Ord. 13232, 07/09/1998 (Map)
Amended by Ord. 13307, 11/06/1998 (Language)
Amended by Ord. 17485, 12/03/2012 (Map) - See adopted 2012 King County Comprehensive Plan, Map Amendment #4

View Map(s) for SO-180. (Click on a map name in the list)

Note: If there are more than one map listed below, there may be a map file ending with a "_x" which provides an index for the remainder of the maps.

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