23.60A.188

A. In shoreline environments where shoreline stabilization is allowed, allowed as a special use, or allowed as a shoreline conditional use, it shall comply with the standards in Section 23.60A.172 and in this Section 23.60A.188 . B. Classification of practices. Shoreline stabilization practices are classified as non-structural measures, soft stabilization, or hard stabilization. C. Geologically hazardous areas. In addition to meeting the standards of this Section 23.60A.188 , an applicant for shoreline stabilization to protect existing principal residential structures in geologically hazardous areas is required to demonstrate that no alternatives, including relocation or reconstruction of existing structures, are feasible and less expensive than the proposed stabilization structures or measures to protect the structure. D. Soft shoreline stabilization shall comply with subsections 23.60A.188.A, 23.60A.188.C, 23.60A.188.G and 23.60A.188.H and the following standards: 1. The size of the soft stabilization measure shall be the minimum necessary. 2. Soft stabilization projects are allowed to extend waterward of the OHW mark, if they do not move the line of the OHW mark waterward. E. New hard stabilization shall comply with subsections 23.60A.188.A, 23.60A.188.C, 23.60A.188.G and 23.60A.188.H and the following standards: 1. New hard stabilization is prohibited unless a geotechnical report conclusively demonstrates that the conditions set out in subsections 23.60A.188.E.1.a, b, c, d, and e exist, except as provided in subsections 23.60A.188.E.2 and 23.60A.188.E.3: a. Existing principal structures or access to existing principal structures: 1) An existing principal structure or access to an existing principal structure is in imminent danger of erosion damage caused by tidal action, currents or waves. Imminent danger is demonstrated by the likelihood of either undermining or loss of lateral support for foundations within three years at a constant rate of erosion or vulnerability to a large one-time event; or 2) Where waiting until an existing principal structure or access to an existing principal structure is in imminent danger as described in subsection 23.60A.188.E.1.a.1 would foreclose the opportunity to use measures that avoid impacts on ecological functions; or 3) An existing water-dependent or water-related use or access to an existing water-dependent or water-related use is in need of protection from erosion and this need is demonstrated through a geotechnical report. b. Erosion is not caused by upland conditions, such as vegetation loss or drainage problems. c. It is infeasible, or sufficient protection is not provided by: 1) First, using nonstructural measures, planting vegetation, or installing on-site drainage improvements; and 2) Second, including or using soft stabilization methods. d. The proposed hard stabilization would prevent or reduce structural damage. e. Installation and maintenance of hard stabilization will not result in adverse impacts to adjacent properties. 2. For ecological restoration and enhancement, or remediation of hazardous substances, the geotechnical report must demonstrate the conditions set out in subsections 23.60A.188.E.1.b, 23.60A.188.E.1.c, and 23.60A.188.E.1.e. 3. Placing hard stabilization in front of the existing hard stabilization structure is allowed if the site is used for at least one of the following: a. The bulkhead or piers on the site are used to moor vessels that are off-loaded or loaded as part of the operation of the use of the site; b. The bulkhead is needed to provide load-carrying land immediately adjacent to the shoreline that allows heavy trucks access to vessels or heavy equipment for the operation of the use of the site; c. The bulkhead and adjacent land is used to provide access to vessels undergoing repair; d. The area adjacent to the bulkhead is used for fuel transfer to vessels; e. The area adjacent to the bulkhead is used for equipment for the operation of the water-dependent or water-related use of the site; or d[f]. The bulkhead is required to provide sufficient depth at the shoreline to allow large, deep draft vessels to moor at the docks allowed within the pier head line. 4. The size of the stabilization measure shall be the minimum necessary. F. Replacement of hard stabilization shall comply with subsections 23.60A.188.A, 23.60A.188.C, 23.60A.188.G and 23.60A.188.H and the following standards: 1. Replacement of existing hard stabilization structures is allowed for: a. water-dependent or water-related uses if it is infeasible to use nonstructural measures, soft stabilization, or if the site is used for the following: 1) The bulkhead or piers on the site are used to moor vessels that are off-loaded or loaded as part of the operation of the use of the site; 2) The bulkhead is needed to provide load-carrying land immediately adjacent to shoreline that allow heavy trucks access to vessels or heavy equipment for the operation of the use of the site; 3) The bulkhead and adjacent land is used to provide access to vessels undergoing repair; 4) The area adjacent to the bulkhead is used for fuel transfer to vessels; 5) The area adjacent to the bulkhead is used for equipment for the operation of the water-dependent or water-related use of the site; 6) The bulkhead is required to provide sufficient depth at the shoreline to allow large, deep draft vessels to moor at the docks allowed within the pier head line; or 7) The bulkhead provides containment of pollution sources to the adjacent water body and is a requirement of an agency mandated cleanup action. b. Ecological restoration and enhancement; c. Remediation of hazardous substances; or d. An existing principal use, principal structure or substantial appurtenant structure that is located 15 feet or less from the OHW mark, or the vertical difference from 5 feet inland of the OHW mark to 5 feet waterward of the OHW mark is greater than 2.5 feet (as illustrated in Exhibit A for 23.60A.188). 2. Replacement of existing hard stabilization is otherwise prohibited unless the applicant demonstrates the need for replacement by providing a geotechnical report establishing that: a. An existing principal structure or substantial appurtenant structure is in imminent danger of erosion damage caused by tidal action, currents, or waves. Imminent danger is demonstrated by the likelihood of either undermining or loss of lateral support for foundations within three years at a constant rate of erosion or vulnerability to a large one-time event; or b. Where waiting until an existing principal structure or access to an existing principal structure is in imminent danger as described in subsection 23.60A.188.E.1.a.1 would foreclose the opportunity to use measures that avoid impacts on ecological functions; and c. Non-structural and soft stabilization will not provide adequate protection, and the proposed hard stabilization will prevent or reduce structural damage. 3. Location and size of replacement of existing hard stabilization a. Replacement of hard stabilization shall not encroach waterward of the ordinary high-water mark or existing structure unless it is to protect a residence that has been continuously occupied since December 31, 1991, and there are overriding safety or environmental concerns. In such cases, the replacement structure shall abut the existing shoreline stabilization structure. b. Replacement of hard stabilization waterward of existing hard stabilization is regulated as new hard stabilization under subsection 23.60A.188.E. 4. The size of the stabilization measure shall be the minimum necessary. 5. Additions to or increases in size of existing hard stabilization shoreline stabilization structures are considered new structures and regulated under subsection 23.60A.188.D. 6. Where a net loss of ecological functions associated with critical saltwater habitats would occur by leaving the existing structure, it shall be removed as part of the replacement measure. Exhibit A for 23.60A.188 Hard Engineering Replacement - One Prequalification Criterion G. Publicly financed or subsidized shoreline stabilization shall not restrict public access to the shoreline except where such access is determined to be infeasible because of incompatible uses, safety, security, or harm to ecological functions. If feasible, the publicly financed or subsidized shoreline stabilization shall incorporate ecological restoration and enhancement and public access improvements into the project. H. Mitigation sequencing 1. In applying mitigation sequencing pursuant to Section 23.60A.158 , adverse impacts on ecological functions from shoreline stabilization include, but are not limited to: a. the impacts on size of substrate and the effects of beach slope on waves; and b. for new or replaced hard stabilization, disturbance of underwater substrate; turbidity; loss or disturbance of food, shelter, spawning, and migration habitat; loss or disturbance of fish runs, biological communities and biodiversity, particularly benthic productivity; and change in water depth including ongoing scouring. Ongoing scouring means the continuation of substrate movement that causes deeper water. 2. In designing a project, the following priorities are established, and these measures are required to be used in the sequence listed below to reduce the adverse impacts of shoreline stabilization, unless the applicant demonstrates that the priority is inapplicable or not feasible, or that a different sequence or technique will be more effective in reducing adverse impacts. a. Approaches to shoreline stabilization. Non-structural practices are required unless infeasible or are not sufficient to provide protection. If non-structural practices are infeasible or insufficient then soft stabilization takes priority over hard stabilization. b. Hard stabilization. For new or replaced hard stabilization, the order of priority is as follows: 1) Riprap; 2) Terraced and stepped bulkheads with an average slope of 30 percent or less; 3) Sloped bulkhead, with a slope of 30 percent or less; 4) Terraced and stepped bulkheads with an average slope that is greater than 30 percent; 5) Sloped bulkhead, with a slope greater than 30 percent; and 6) Vertical bulkhead. (Ord. 124105 , § 3, 2013.)