Volume 2: Draft Gorst Planned Action Environmental Impact Statement

GORST PLANNED ACTION EIS | APPENDICESTable D-3. Gorst Creek Management Zones – Preliminary ApproachManagement Zone Habitat Standards Impervious SurfaceAllowancesStructure AllowancesA: 0-50 feet upland ofOHWMA-1: Retain significant native trees,shrubs, and ground cover consistentwith shoreline master program,critical area, and landscaperegulations.A-2: In exchange for impervioussurface allowances, enhancedegraded areas of ManagementZone A, as follows: Enhance at a 2:1ratio the equivalent of the clearedarea with native vegetation orremove man-made structures instream.1A-3: If existing impervious area of anequivalent or greater area isremoved from Management Zone A,enhance degraded areas ofManagement Zone A, as follows:Enhance at a 1:1 ratio theequivalent of the cleared area withnative vegetation, or remove manmadestructures in stream at aminimum of 50% of property’s linealfeet of shoreline frontage based onan approved habitat managementplan.1Installation of pervious or semipervioussurfaces such as non-solidsurface decks or greeninfrastructure in place of existinglawn or other non-nativevegetation. The area of suchsurfaces shall not be greater than25% of Management Zone A area,and shall meet Type A-2 or A-3habitat standards.Perpendicular trails constructed ofpermeable materials and nogreater in travel way width than 6feet subject to Type A-2 or A-3habitat standards.No new structures withpermanent foundations areallowed.B: 50-85 feet upland ofOHWMB-1: Same as A-1.B-2: In exchange for impervioussurface allowances, enhancedegraded areas in ManagementZone A, as follows: Enhance at a 1:1ratio the equivalent of the clearedarea with native vegetation orremove man-made structures instream. 1B-3: In exchange for structureallowances, achieve both of thefollowing:i. Plant significant native trees toachieve 65% coverage ofManagement Zone A Area. 1ii. Enhance Management Zone B:Enhance at a 2:1 ratio theequivalent of the cleared area withnative vegetation or remove manmadestructures in stream orremove man-made structures instream at a minimum of 50% ofproperty’s lineal feet of shorelinefrontage based on an approvedhabitat management plan.1Installation of pervious or semipervioussurfaces such as non-solidsurface decks or greeninfrastructure in place of existinglawn or other non-nativevegetation, and when meeting B-2habitat standards. Or placement ofimpervious surfaces that complywith all storm water standards andHabitat Standards B-3. Themaximum impervious surfaceallowance by itself shall notexceed 25% of Management ZoneB area. In combination, imperviousand structural allowances shall notexceed 35% of Management ZoneB area.Trails, parallel or perpendicular,constructed of permeablematerials and no greater in travelway width than 6 feet subject toHabitat Standard B-2.None with Type B-1vegetation standards.Structures allowed in up to25% of Management Zone Bif meeting Type B-3 habitatstandards. Except that themaximum impervioussurface allowance andstructural allowance shallnot exceed 35% incombination.D-9