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• Wetland name or number <br /> HGM Classification of Wetland in Western Washington <br /> For questions 1 -7,the criteria described must apply to the entire unit being rated. <br /> If hydrologic criteria listed in each question do not apply to the entire unit being rated,you probably have a unit <br /> with multiple HGM classes. In this case,identify which hydrologic criteria in questions 1 7 apply, and go to <br /> Question 8. <br /> 1. Are the water levels in the entire unit usually controlled by tides except during floods? <br /> O NO-go to 2 0 YES-the wetland class is Tidal Fringe-go to 1.1 <br /> 1.1 Is the salinity of the water during periods of annual low flow below 0.5 ppt(parts per thousand)? <br /> El NO -Saltwater Tidal Fringe (Estuarine) 0 YES-Freshwater Tidal Fringe <br /> If your wetland can be classified as a Freshwater Tidal Fringe use the forms for Riverine wetlands, <br /> If it is Saltwater Tidal Fringe it is an Estuarine wetland and is not scored. This method cannot be <br /> used to score functions for estuarine wetlands. <br /> 2. The entire wetland unit is flat and precipitation is the only source(>90%) of water to it. <br /> Groundwater and surface water runoff are NOT sources of water to the unit. <br /> El NO-go to 3 0 YES-The wetland class is Flats <br /> If your wetland can be classified as a Flats wetland, use the form for Depressional wetlands. <br /> 3. Does the entire wetland unit meet all of the following criteria? <br /> O The vegetated part of the wetland is on the shores of a body of permanent open water(without any <br /> plants on the surface at any time of the year)at least 20 ac(8 ha) in size; <br /> O At least 30% of the open water area is deeper than 6.6 ft(2 m). <br /> O NO-go to 4 0 YES -The wetland class is Lake Fringe (Lacustrine Fringe) <br /> 4. Does the entire wetland unit meet all of the following criteria? <br /> El The wetland is on a slope(slope can be very gradual), <br /> 121 The water flows through the wetland in one direction (unidirectional) and usually comes from seeps. <br /> It may flow subsurface,as sheetflow,or in a swale without distinct banks. <br /> O The water leaves the wetland without being impounded. <br /> D NO-go to 5 El YES-The wetland class is Slope <br /> NOTE:Surface water does not pond in these type of wetlands except occasionally in very small and shallow <br /> depressions or behind hummocks (depressions are usually<3 ft diameter and less than 1 ft deep). <br /> 5. Does the entire wetland unit meet all of the following criteria? <br /> ❑ The unit is in a valley, or stream channel,where it gets inundated by overbank flooding <br /> from that stream or river, <br /> ❑ The overbank flooding occurs at least once every 2 years. <br /> Cl NO-go to 6 0 YES-The wetland class is Riverine <br /> NOTE:The Riverine unit can contain depressions that are filled with water when the river is not flooding. <br /> Wetland Rating System for Western WA:2014 Update <br /> Rating Form-Effective January 1,2015 3 WSDOT Adapted Form-March 2,2015 <br />