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Wetland name or number <br /> R Riverine and Freshwater Tidal Fringe Wetlands <br /> HYDROLOGIC FUNCTIONS - Indicators that wetland functions to reduce flooding and stream erosion <br /> R 3.Does the wetland have the potential to reduce flooding and erosion? (seep. 54) <br /> R R 3.1 Characteristics of the overbank storage the wetland provides: <br /> Estimate the average width of the wetland perpendicular to the direction of the flow and the <br /> width of the stream or river channel(distance between banks). Calculate the ratio: (width of <br /> wetland)/(width of stream). <br /> If the ratio is more than 20 intc= • 6 <br /> If the ratio is between 10—20 . oints=6 <br /> If the ratio is 5-<10 points=4 <br /> If the ratio is 1-<5 points=2 <br /> If the ratio is< 1 points= 1 <br /> R R 3.2 Characteristics of vegetation that slow down water velocities during floods: Treat large <br /> woody debris as `forest or shrub". Choose the points appropriate for the best description. <br /> (polygons need to have>90%cover at person height NOT Cowardin classes) <br /> Forest or shrub for>1/3 area OR Emergent plants>2/3 area Z points=7 7 <br /> Forest or shrub for>1/10 area OR Emergent plants> 1/3 area points=4 <br /> Vegetation does not meet above criteria points=0 <br /> R Total for R 3 Add the points in the boxes above ' 13 <br /> R R 4.Does the wetland have the opportunity to reduce flooding and erosion? (seep.57) <br /> Answer YES if the wetland is in a location in the watershed where the flood storage,or reduction in <br /> water velocity,it provides helps protect downstream property and aquatic resources from flooding <br /> or excessive and/or erosive flows. Note which of the following conditions apply. <br /> ® There are human structures and activities downstream(roads,buildin s,bridges,farms) <br /> that can be damaged by flooding. <br /> ❑ There are natural resources downstream(e.g.salmon redds)that can e damaged by <br /> flooding multiplier <br /> ❑ Other 2 <br /> (Answer NO if the major source of water to the wetland is controlled by a reservoir or the wetland is <br /> tidal fringe al.• -• _ •- • a dike) <br /> • 'iplier is 2 NO multiplier is 1 <br /> R TOTAL -Hydrologic Functions Multiply the score from R 3 by R 4 26 <br /> Add score to table on p.1 <br /> Wetland Rating Form—western Washington 6 August 2004 <br /> Version 2 Updated with new WDFW definitions Oct.2008 <br />