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Wetland name or number A <br />Classification of Wetland Units in Western Washington <br />If the hydrologic criteria listed in each question do not apply to the entire unit being <br />rated, you probably have a unit with multiple HGNII classes. In this case, identify which <br />hydrologic criteria in questions 1-7 apply, and go to Question 8, <br />1. Arc the water levels in the entire unit usually controlled by tides (i.e. except during floods)? <br />0NO — go to 2 ❑ YES — the wetland class is Tidal Fringe <br />if yes, is the salinity of the water daring periods of annual low flow below 0.5 ppt (parts per <br />thousand)? YES —Freshwater Tidal Fringe — Saltwater Tidal Fringe (Estuarine) <br />Ifyour we tlan`d-can be classified as a Freshwaie�. al Fringe use the forms for Riverine <br />wetlands. if it is Saltwater Tidal Fringe it is rated as an Estuarine wetland Wetlands that <br />were called estuarine in the first and second editions of the rating system are called Salt <br />Water Tidal Fringe in the Hydrogeomorphic Classification. Estuarine wetlands were <br />categorized separately in the earlier editions, and this separation is being kept in this <br />revision. To maintain consistency between editions, the term "Estuarine" Wetland is kept. <br />Please note, however, that the characteristics that define Category 1 and II estuarine <br />wetlands have changed (see p. ). <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 />❑✓ NO — go to 3 ❑YES —The Wetland class is Flats <br />If your wetland can be classified as a "Flats" wetland, use the form for Depressional <br />wetlands. <br />3. Does the entire wetland unit meet both of the following criteria? <br />_The vegetated part of the wetland is on the shores of a body of permanent open water <br />(without any vegetation on the surface) at least 20 acres (8 ha) in size; <br />_At least 30% of the open water area is deeper than 6.6 ft (2 in)?Q O --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 />s7—The water flows through the wetland in one direction (unidirectional) and usually <br />comes from seeps, It may flow subsurface, as sheetflow, or in a swalc without <br />distinct banks. <br />✓ The water leaves the wetland without being impounded? <br />NOTE; Surface water does not pond in these type of wetlands except occasionally in <br />vcry,small and shallow depressions or behind hummocks (depressions are usually <br /><3ft diameter and less than I foot deep). <br />❑ NO - go to 5 ❑✓ YES —Tlic Wetland class is Slope <br />Wetland name or number A <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 <br />flooding from that stream or river <br />_ The overbank flooding occurs at least once every two years. <br />NOTE: The riverine unit can contain depressions that are filled ivith water when the river is <br />not flooding. <br />❑NO - go to 6 ❑YES — The wetland class is Riverine <br />6. Is the entire wetland unit in a topographic depression in which water ponds, or is saturated to the <br />surface, at some time during the year. This means that anv outlet, if present, is higher than the <br />interior of the wetland <br />ONO— go to 7 DYES —The wetland class is Depressional <br />7. Is the entire wetland unit located in a very flat area with no obvious depression and no overbank <br />flooding. The unit does not pond surface water more than a few inches. The unit seems to be <br />maintained by high groundwater in the area. The wetland may be ditched, but has no obvious <br />natural outlet. <br />[:]NO —go to 8 DYES —The Wetland class is Depressional <br />8, Your wetland unit seems to be difficult to classify and probably contains several different HGM <br />clases. For example, seeps at the base of a slope may grade into a riverine floodplain, or a steal I <br />stream within a depressional wetland has a zone of flooding along its sides. GO BACK AND <br />IDENTIFY WHICH OF THE HYDROLOGIC REGIMES DESCRIBED iN.QUESTiONS 1-7 <br />APPLY TO DIFFERENT AREAS IN THE UNIT (make a rough sketch to help you decide). Use <br />the following table to identify the appropriate class to use for the rating system if you have several <br />HGM classes present within your wetland. NOTE: Use this table only if the class that is <br />recommended in the second column represents 10% or more of the total area of the wetland unit <br />being rated. I£the area of the class listed in column 2 is less than 10% of the unit; classify the <br />wetland using the class that represents more than 90% of the total area. <br />HGM Classes within the welland unit beh rated <br />HGjLI Class to Use in Rati <br />Slope + Riverine <br />Riverine <br />Slope + Deressional <br />Dc ressional <br />Slope + Lake-frina <br />Lake -fringe <br />Depressional + Riverine along stream within boundary <br />Depressional <br />Depressional + Lakc-fringc <br />Dc ressional <br />Salt Water Tidal Fringe and any other class of freshwater <br />wetland <br />Treat as ESTUARINE under <br />wetlands with special ❑ <br />characteristics <br />If you are unable still to determine which of the above criteria apply to your wetland, or if you <br />have more than 2 HGM classes within a Wetland boundary, classify the wetland as Depressional <br />for the rating. <br />Wetland Rating Form —western Washington 3 August 2004 Wetland Rating Form —western Washington 4 August 2004 <br />version 2 version 2 <br />