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