Summary

These standards limit the allowable amount of site disturbance on lots in Holmes Point to reduce visual impacts of development, maintain community character and protect a high proportion of the undisturbed soils and vegetation, tree cover and wildlife, and require an inspection of each site and the area proposed to be cleared, graded and built on prior to issuance of a building permit.

Story

Amended by Ord. 15244, 08/11/2005 (Map)

Description

Holmes Point Site Disturbance P-suffix Conditions

Development Condition Text

Minimum Site Disturbance Property-Specific Development Standards and Area Zoning Map

A. Purpose. The purpose of the minimum site disturbance development standards is to allow infill at urban densities while providing an increased level of protection for the Holmes Point study area, an urban residential area characterized by a predominance of sensitive environmental features including but not limited to steep slopes, landslide hazard areas and erosion hazard areas, and further characterized by a low level of roads and other impervious surfaces relative to undisturbed soils and vegetation, tree cover and wildlife habitat. These standards limit the allowable amount of site disturbance on lots in Holmes Point to reduce visual impacts of development, maintain community character and protect a high proportion of the undisturbed soils and vegetation, tree cover and wildlife, and require an inspection of each site and the area proposed to be cleared, graded and built on prior to issuance of a building permit.

B. Standards. Within the parcels listed below and shown on the accompanying map, the minimum density, maximum density and maximum impervious surface standards set forth in K.C.C. 21A.12.030A are superseded by this p-suffix, and the following development standards shall be applied to all residential development proposed after the effective date of this ordinance:

1. Where the underlying classification is R-8, the base and maximum density shall be eight dwelling units per acre, and there is no minimum density;

2. Where the underlying classification is R-6, the base and maximum density shall be six dwelling units per acre, and there is no minimum density;

3. Where the underlying classification is R-4, the base and maximum density shall be four dwelling units per acre, and there is no minimum density;

4. When review under K.C.C. chapter 21A.24 (Sensitive Areas) or the King County Surface Water Design Manual is required, the review shall assume the maximum development permitted by this p-suffix condition will occur on the subject property, and the threshold of approval shall require a demonstration of no significant adverse impact on properties located downhill or downstream from the proposed development.

5. Total building coverage and all other impervious surfaces shall be limited within every building lot as follows:

a. On lots up to six thousand five hundred square feet in size, two thousand six hundred square feet;

b. On lots six thousand five hundred and one to nine thousand square feet in size, two thousand six hundred square feet plus twenty eight percent of the lot area over six thousand five hundred square feet;

c. On lots over nine thousand square feet in size, three thousand three hundred square feet plus ten percent of the lot area over nine thousand square feet;

d. On a lot already developed, cleared or otherwise altered up to or in excess of the limits set forth above prior to the effective date of the application of this p-suffix condition, new impervious surfaces shall be limited to five percent of the area of the lot, not to exceed 750 square feet;

e. The limits set forth in this section are to be measured at grade level; the area of an allowable impervious surface shall not be calculated to include above-grade unsupported projections such as eaves or cantilevered bays or decks; and

f. For purposes of computing the allowable impervious surface within each lot, private streets, joint-use driveways or other impervious-surfaced access facilities required for vehicular access to a lot in easements, access panhandles or other areas excluded from the lot width circle used to measure lot width as provided in K.C.C. 21A.12.050B shall be excluded from calculations.

6. In addition to the maximum area allowed for buildings and other impervious surfaces under subsection B.5, up to 50 percent of the total lot area may be used for garden, lawn or landscaping, provided:

a. all significant trees, as defined in K.C.C. chapter 21A.06, must be retained. The limits set forth in this subsection are to be measured at grade level; the area of allowable garden, lawn or landscaping may intrude into the drip line of a significant tree required to be retained under this subsection if it is demonstrated not to cause root damage or otherwise imperil the tree's health;

b. total site alteration, including impervious surfaces and other alterations, shall not exceed 75 percent of the total lot area; and

c. if development on the lot is to be served by an on-site sewage disposal system, any areas required by the department of public health to be set aside for on-site sewage disposal systems shall be contained as much as possible within the portion of the lot altered for garden, lawn or landscaping as provided by this subsection. If elements of the on-site sewage disposal system must be installed outside the landscaped area, the elements must be installed so as not to damage any significant trees required to be retained under subsection B.6.a, and any plants that are damaged must be replaced with similar native plants.

7. Subdivisions, short subdivisions and conditional use permits for more than one dwelling unit shall be subject to the following requirements:

a. New public or private road improvements shall be the minimum necessary to serve the development on the site in accordance with King County Road Standards. King County shall consider granting variances to the road standards to further minimize site disturbance, consistent with pedestrian and traffic safety, and the other purposes of the road standards; and

b. Impervious surfaces and other alterations within each lot shall be limited as provided in subsections 5 and 6. In townhouse or multifamily developments, total impervious surfaces and other alterations shall be limited to two thousand six hundred square feet per lot or dwelling unit in the R-6 and R-8 zones, and three thousand three hundred square feet per lot or dwelling unit in the R-4 zone.

8. The Department of Development and Environmental Services or its successor agency (DDES) shall conduct site inspections prior to approving any site alteration or development on parcels subject to this p-suffix condition as follows:

a. Prior to issuing a permit for alteration or building on any individual lot subject to this p-suffix condition, DDES shall inspect the site to verify the existing amount of undisturbed area, tree and other plant cover, and any previous site alteration or building on the site. Prior to this inspection and prior to altering the site, the applicant shall clearly delineate the area of the lot proposed to be altered and built on with environmental fencing, high-visibility tape or other conspicuous and durable means, and shall depict this area on a site plan included in the application.

b. Prior to issuing a preliminary short subdivision approval, conditional use permit or building permit for more than one dwelling unit, or preliminary subdivision approval on any parcel subject to this p-suffix condition, DDES shall inspect the site to verify the amount of undisturbed area, tree and other plant cover, and any previous site alteration or building on the site. Prior to this inspection and prior to altering the site, the applicant shall clearly delineate the area of the proposed grading for streets, flow control and other common improvements, with environmental fencing, high-visibility tape or other conspicuous and durable means, and shall depict this area on a plot plan included in the application. Development of individual lots within any approved subdivision or short subdivision shall be subject to an individual inspection in accordance with subsection a.

c. Applicants will be assessed a non-refundable hourly fee for all inspections required by this subsection, consistent with K.C.C. Title 27, as amended.

9. Areas not covered by impervious surfaces or altered as provided in subsections 5, 6 or 7, which are not sensitive areas governed by K.C.C. chapter 21A.24, shall be maintained in an undisturbed state, except for the following activities:

a. Incidental trimming or removal of vegetation necessary for protection of property or public health and safety, or the incidental removal of vegetation to be used in the celebration of recognized holidays. Replacement of removed hazardous trees may be required;

b. Areas infested by noxious weeds may be replanted with appropriate native species or other appropriate vegetation;

c. Construction of primitive pedestrian-only trails in accordance with the construction and maintenance standards in the U.S. Forest Service "Trails Management Handbook" (FSH 2309.18, June 1987, as amended) and "Standard Specifications for Construction of Trails" (EM-7720-102, June 1996, as amended); but in no case shall trails be constructed of concrete, asphalt or other impervious surface;

d. Limited trimming and pruning of vegetation for the creation and maintenance of views, and the penetration of direct sunlight, provided the trimming or pruning does not cause root damage or otherwise imperil the tree's health as allowed for in K.C.C. 21A.24.310D.4; and

e. Individual trees or plants may be replaced with appropriate species on a limited basis. Forested hydrological conditions, soil stability and the duff layer shall be maintained.

10. Conformance with this p-suffix condition shall not relieve an applicant from conforming to any applicable provisions of K.C.C. chapter 21A.24.

C. Variations from Standards. For development activity occurring after the effective date of the application of this p-suffix condition, upon written request from the applicant, the director of DDES may allow up to a ten percent increase in impervious surface on individual lots over the limits set forth in Section B above, provided such increase is the minimum necessary to allow reasonable use of the property and meets all other applicable decision criteria for a variance as provided in K.C.C. 21A.44.030, and one or more of the following circumstances applies:

1. Development of a lot will require a driveway sixty feet or longer from the lot boundary to the proposed dwelling unit;

2. On-site flow control facilities are required by the King County Water and Land Resources Division or its successor agency;

3. The requested increase will allow placement of new development on the site in such a way as to allow preservation of one or more additional significant trees, as defined in K.C.C. chapter 21A.06, that would otherwise be cleared; or

4. The requested increase is necessary to provide additional parking, access ramp or other facilities needed to make a dwelling accessible for a mobility-impaired resident.

Ordinance

13576

Effective Date

July 22, 1999

Changes

Amended by Ord. 15244, 08/11/2005 (Map)

View Map(s) for NS-P23. (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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