Item B: Ordinance Concerning Goal 5 Natural Resources Study

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NO.1 10/18/05 (b) Output from all other light sources shall be no more than an average maintained luminance of 0.9 foot-candle at grade. (c) All lighting fixtures shall be designed to direct light downward to areas intended for human use after dark, and shall be shielded such that light shining toward /WR conservation areas is minimized to the maximum extent practicable. (9) Trails. Within the /WR conservation area, trails shall be constructed of gravel, wood chips or other pervious material, unless otherwise approved by the city manager or decision-maker. Trail construction shall involve the least removal of native vegetation practicable for the area and the minimum amount of fill or excavation practicable. (10) Stream and Channel Crossings. Bridges or other structures that cross streams or wetlands within the /WR conservation area or areas removed from the /WR conservation area shall be constructed so that water flow, vegetation growth and movement of aquatic animals and water dependent wildlife are impeded to the least extent practicable. To meet this standard, bridges and crossings shall include, but are not limited to, applicable items from the following list: (a) Bridges across Category A or Category B streams as identified in the Goal 5 Water Resources Conservation Plan shall, where practicable, be designed to avoid channel constriction when flows reach the top of high bank. Where practicable, bridges shall span a distance 1.2 times the width of the stream channel from top of high bank to top of high bank to help prevent scouring within the structure or at the outlet during less frequent floods. (b) Crossings over Category A or Category B streams as identified in the Goal 5 Water Resources Conservation Plan shall utilize bridges or natural substrate culverts where possible. Where practicable, the lower lip of any natural substrate culvert shall be embedded at least 1 foot for box culverts and pipe arches, and at least 25% of the pipe diameter for pipe culverts. The substrate within the structure shall match the composition of the substrate in the natural stream channel at the time of construction. The substrate shall either resist displacement during flood events or the structure shall be designed to maintain an appropriate bottom through natural bed load transport. (c) Bridges and culverts on Category A or Category B streams as identified in the Goal 5 Water Resources Conservation Plan shall be constructed so that the "openness ratio" of the structure is equal to or greater than 0.25. The "openness ratio" is the cross-sectional area of the passage area under or within the structure divided by the length of the stream segment it crosses over. For a box culvert, the openness ratio shall be (height x width)/Iength. (d) Culverts shall not substantially increase or decrease water depth or flow rate conditions upstream or downstream from the culvert. (e) The lower lip of all culverts shall meet the stream or channel bed at or below grade. (f) Culverts shall be the minimum length practicable, and fill on top of the culvert shall have the minimum footprint practicable. (11) Interpretive Facilities. Within the/WR conservation area, boardwalks, viewing platforms, interpretive information kiosks, trail and interpretive Ordinance - 19