Development proposals on sites containing class I and class II landslide hazards shall meet the following requirements:
A. Buffer Requirement: A buffer shall be established from all edges of landslide hazard areas. The size of the buffer shall be determined by the city administrator to eliminate or minimize the risk of property damage, death, or injury resulting from landslides caused in whole or part by the development, based upon review of and concurrence with a landslide hazard special study. The buffer shall be equal to the height of the slope or fifty feet (50'), whichever is greater. The buffer may be reduced when a qualified professional demonstrates to the city administrator's satisfaction that the reduction will adequately protect the proposed development, adjacent developments, and uses and the subject critical area. The buffer may be increased where the city administrator determines a larger buffer is necessary to prevent risk of damage to proposed and existing development.
B. Alterations: Alterations of a landslide hazard area and/or buffer may only occur for activities for which a hazards analysis is submitted and certifies that:
1. The development will not increase surface water discharge or sedimentation to adjacent properties beyond predevelopment conditions;
2. The development will not decrease slope stability on adjacent properties; and
3. Such alterations will not adversely impact other critical areas.
C. Impervious Surface Ratio: An impervious surface ratio is a measurement of the amount of the site that is covered by any material that substantially reduces or prevents the infiltration of stormwater into previously undeveloped land. Impervious surfaces are defined in Title 9, Chapter 5A, Section 4 of this code. The maximum impervious surface ratios for class I and class II landslide hazard areas are set forth in table 2 of this section.
D. Native Vegetation: Native vegetation is plant species that are indigenous and naturalized to the Orting region and which can be expected to naturally occur on a site. Native vegetation does not include noxious weeds. The minimum percentage of native vegetation that must be retained on sites including class I or class II landslide hazard areas is set forth in table 2 of this section.
TABLE 2
IMPERVIOUS SURFACE AND NATIVE VEGETATION REQUIREMENTS FOR LANDSLIDE HAZARD AREAS
IMPERVIOUS SURFACE AND NATIVE VEGETATION REQUIREMENTS FOR LANDSLIDE HAZARD AREAS
Landslide Hazard Class | Maximum Impervious Surface Ratio | Minimum Percentage Of Native Vegetation Retained |
Class II | 0.30 | 65% |
Class I | 0.20 | 75% |
E. Development Design:
1. Structures and improvements shall be clustered to retain as much open space as possible and to preserve the natural topographic features of the site.
2. Structures and improvements shall conform to the natural contour of the slope.
3. Structures and improvements shall be located to preserve the most critical portion of the site and its natural landforms and vegetation.
4. The use of retaining walls which allow the maintenance of existing natural slope area is preferred over graded artificial slopes.
F. Additional Standards For Class I Landslide Hazards:
1. Alteration of class I landslide hazard areas is permitted only if the development proposal can be designed so that the landslide hazard to the project and the adjacent property is eliminated or mitigated and the development proposal on that site is certified as safe by a geotechnical engineer licensed in the state of Washington.
2. Development or alteration shall be prohibited on parcels with a lot slope of greater than forty percent (40%). These parcels shall be eligible for transfer of development rights as set forth in subsection G of this section.
G. Transfer Of Development Rights:
1. The idea of transfer of development rights is based upon the legal concept of property law that the right to develop real estate is one of the "bundle of rights" included in fee simple ownership of land. Fee simple ownership of real estate allows the owner to sell, lease, or trade any one or all of the "bundle of rights" to his property which includes the right to use, lease, sell, or abandon the property or any of its components of ownership not retained by a previous owner such as mineral, oil, gas, air, and/or development rights. These rights of ownership are subject to the limitation and legislative powers of the local government.
2. A development right is a simple extension of the rights normally associated with land ownership. When legally established a development right has value separate from the land itself. It can be subject to reasonable regulation by local government under the police power. The development right can be transferred by the owner, by means of gift or sale, to another property. The landowner may sell the development rights and still retain the title to the land and the right to use the surface of the land on a limited basis.
3. For the purposes of this chapter, the owner of any vacant and/or undeveloped parcel of land with a lot slope of greater than forty percent (40%) may transfer the development rights (TDR) allocated to the parcel of land to any person at any time.
4. The planning commission shall consider the request for TDR at the public hearing for the land use proposal for the receiving parcel.
5. To assure that the sending parcel is adequately protected, a restriction shall be placed on the deed which expressly restricts the use of said property in perpetuity to open space uses. The restriction shall be required regardless of the number of dwelling units for which the development rights are transferred. A memorandum of agreement (MOA) between the applicant and the city shall be recorded with the city clerk. The MOA shall refer to all deed restrictions related to the property.
6. TDR shall not exceed the number of dwelling units which would be allowed on the sending parcel according to the zoning designation of the sending parcel, if there were no development restrictions tied to steep slopes. This number of dwelling units shall be equal to the number of dwelling units that could be produced on the parcel if the sending parcel were subdivided in terms of the minimum requirements of the underlying zone as evidenced by a preliminary plan sketch.
7. TDR may go to more than one receiving parcel; however, this shall not increase the total number of transferred dwelling units which are allowed.
8. The increased number of dwelling units on the receiving parcel shall not be more than twenty five percent (25%) above the number of dwelling units allowed according to the zoning designation on the receiving parcel(s).
9. TDR shall be allowed only if the land use proposal on the receiving parcel(s) is designed in such a way that the increased density:
a. Is consistent with any land use plan associated with the receiving parcel and with goals, purposes, and intents of the zoning designation of the receiving parcel; and
b. Is compatible with the existing and likely future developments in the vicinity; and
c. Adequately addresses infrastructure, natural and other constraints, and does not result in significant environmental impacts.
10. TDR shall not be approved until final plat approval or other final approval for the receiving parcel is granted by the city council.
(Ord. 806, 6-30-2005; amd. Ord. 958, 7-9-2014; Ord. 2019-1057, 1-8-2020)