Ord-2021-016 - Laserfiche WebLink

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documented in a qeolooicallv hazardous area risk assessment andior qeotechnical report:f. The proposed alterations will not adversely imoact other critical areas; andq. Structures and improvements are desiqned to minimize alterations to the erosive soils and slopes. 2. Ghannel Miqration Zones. lf Countv maps or consultation bv the Director with qualified professionals or aqencies with expertise indicate that a potential channel miqration zone hazard exists on or adiacent to a orooosed develooment site. the aoolicant shall either:a. Locate the proposed development outside of an alreadv defined channel migration hazard area as indicated on the map: orb. Submit a Channel Mioration Zone Report. as described in KCC 174.06.100 prepared bv a qualified qeologist. or engineerino qeoloqist. or professional enqineer, licensed in the state of Washinqton with experience in analyzino channelresponse in the fluvialsystems of the Pacific Northwest.3. Permitted Alterations and Development in Channel Miqration Zones. The followino alterations and develooment shall be allowed as specified below and orevious sections:a. Surface Water Discharqe. Discharoe of surface water, provided there are no other alternatives for discharqe. The pipe shall be located on the surface of the qround and be properlv anchored so that it will continue to function under erosion conditions and not create or contribute to adverse effects on downstream critical areas.b. Utilitv Lines. Utility lines, when no feasible location is available. Above-qround lines shall be anchored and/or desioned so that it will not preclude or interfere with channel mioration. Below qround lines shall be of sufficient depth as to not be affected bv future channel migration.c. Public Roads. Bridqes. and Trails. Public roads. bridqes. and trails when no feasible alternative aliqnment is available. Facilities shall be desiqned such that the roadwav prism and/or bridqe structure will not be susceptible to damaqe from active erosion.d. Stream Bank Stabilization. Stream bank stabilization mav be permitted subiect to allof the standards listed in KCC 174.04.050.4. CMZ Buffers or Setbacks. Based upon the results of the channel miqration zone assessment. the Director shall prohibit or limit use or develooment within a channel mioration zone and mav require a setback or a buffer of undisturbed natural veqetation from the edge of the channel miqration zone in accordance with the followinq: a. The size of the setback or buffer shall be based on the findinqs of a qualified enqineer. engineerinq qeologist. or qeologist. licensed in the state of Washinqton. and shall orotect critical areas and processes and minimize the risk of property damaqe. death. or iniury resultino from channel miqration: b. The buffer shall include the area subiect to bank failure as a result of erosion: andc. lf the desiqnated buffer lacks adequate woodv veoetation. the Director shall have the authority to require veqetation enhancement or other measures to improve natural channel processes and large wood recruitment. 17A.06.060 Alluvial Fan Hazard Standards 1. Permitted Alteration and Development. Alluvial fan hazards will be determined bv Countv maps. LIDAR. and aerial ohotography. The followinq alterations and development may be allowed in alluvial fan hazard areas. after accountinq for restrictions defined bv other critical area regulations. when all reasonable measures have been taken to minimize risks and other adverse effects associated with alluvial fan hazards. and when the amount and deqree of alteration are limited to the minimum needed to accomplish the alteration or development:a. Roads. Utilities. Bridqes. and Other lnfrastructure. Roads. utilities. bridqes. and other infrastructure when located and desiqned to prevent adverse impacts on critical 54