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B. ALTERATIONS. Daylighting and meandering of watercourses is encouraged. <br />Culvert replacement is required where applicable, and upgrades are required to meet <br />State standards. Piping, dredging, diverting or rerouting is discouraged. Culverts are <br />piped segments of streams that flow under a road, trail or driveway. Daylighting of a <br />stream refers to taking a stream out of a pipe that is flowing underground, but not <br />necessarily under a road. All watercourse alterations shall be carried out as specified by <br />the State Department of Fish and Wildlife in accordance with an approved Hydraulic <br />Project Approval (HPA). <br />1. The City encourages daylighting of a watercourse that is located in a pipe or <br />meandering of a previously altered watercourse to restore the stream to a more natural <br />and open condition. As an incentive for daylighting, the Director may approve reduced <br />buffers or setbacks. Daylighting or meandering of a watercourse is only permitted if the <br />following criteria are met: <br />a. The values and functions of the watercourse are improved, including <br />reducing stream flow during storm and flood events, and providing fish and wildlife habitat. <br />b. No adverse impact to fish are expected to occur. <br />c. Water quality is equal or better than existing condition. <br />d. Hydraulic capacity is maintained within the new channel. <br />e. The watercourse design complies with the Washington Department of <br />Fish and Wildlife Water Crossing Design Guidelines Manual 2013 as it now reads and <br />hereafter updated or amended. <br />2. On properties with culverts that are being developed or re -developed, or <br />when stream crossings in public or private rights -of -way are being replaced, existing <br />culverts that carry fish -bearing watercourses or those that could bear fish (based on the <br />criteria in WAC 222-16-031, Washington Forest Practices Rules and Regulations) shall <br />be upgraded to meet the standards in the Washington Department of Fish and Wildlife <br />Water Crossing Design Guidelines Manual 2013, or as amended, if technically feasible. <br />Any culvert replacement shall comply with the following criteria: <br />a. The values and functions of the watercourse are improved including <br />reducing stream flow during storm and flood events, and providing fish and wildlife habitat. <br />b. No adverse impact to fish are expected to occur. <br />c. Water quality is equal or better than existing condition. <br />d. Hydraulic capacity is maintained within the new channel. <br />e. The watercourse design complies with the Washington Department of <br />Fish and Wildlife Water Crossing Design Guidelines manual 2013 as it now reads and <br />hereafter updated or amended. <br />3. Piping, dredging, diverting or rerouting of any watercourse shall be avoided, <br />if possible. Relocation of a watercourse or installation of a bridge is preferred to piping. If <br />piping occurs in a watercourse, it shall be limited to the degree necessary for stream <br />crossings for access. Additionally, these alterations may only occur with the permission <br />of the Director as a Type 2 decision and subject to mitigation sequencing and an approved <br />w:\Legislative Development\Critical Areas update 2-25-20 <br />MD:bjs Review and analysis by Barbara Saxton Page 31 of 87 <br />