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This feature class was developed as a cooperative project between the Department of Natural Resources Forest Practices Division, the Department of Ecology, and the Olympic National Forest. The data set was designed as a polygon coverage, delineated on 1:250,000- scale map overlays and digitized in 1991. It was plotted and proofed, but not completed at that time. Beginning in August, 1994 the coverage STRMTEMP was edited, corrected, and proofed. The data set is now a polygon feature class and shows only Class AA, A, and B polygons. It does not address Lake Class completely (some lakes are delineated, some not); see notes below for explanation. Specific conditions of certain stream segments are also not addressed by the feature class. The WAC MUST be referred to whenever this data set is used. The 1991 MPL coverage was used in delineating the extent of AA polygons. Changes through time in Federal land boundaries may affect the classification of waters in those lands. SUMMARY OF TEMPERATURE CLASSIFICATIONS DESIGNATED IN CHAPTER 173-201A WAC WATERQUALITY STANDARDS FOR SURFACE WATERS OF THE STATE OF WASHINGTON WAC 173-201A-030 General water use and criteria classes (1) Class AA (extraordinary) Temperature shall not exceed 16.0 degrees C (freshwater) or 13.0 degrees C (marine water) due to human activities. (2) Class A (excellent) Temperature shall not exceed 18.0 degrees C (freshwater) or 16.0 degrees C (marine water) due to human activities. (3) Class B (good) Temperature shall not exceed 21.0 degrees C (freshwater) or 19.0 degrees C (marine water) due to human activities. (4) Class C (fair) Temperature shall not exceed 22.0 degrees C due to human activities. For all of the above classes, when natural conditions exceed the listed temperature, no temperature increases will be allowed which will raise the receiving water temperature by greater than 0.3 degrees C. (5) Lake Class Temperature - no measurable change from natural conditions. *** Notes regarding WAC 173-201A sections 130 and 140 - Specific classifications for fresh and marine waters: All lakes and their feeder streams are classified as Lake Class. In this data set some large lakes and their feeder streams have had polygons created around them. These are shown as Class AA. Many lakes too small to be separately delineated may be contained within Class B, A, or AA polygons. Some stream segments have special conditions applied to their temperature standards. These conditions are listed in the WAC but are not delineated in the polygon coverage. These include the Columbia River, Duwamish River, Grande Ronde River, Hoquiam River, Lake Washington Ship Canal, Mill Creek (near Walla Walla), Palouse River, Pend Oreille River, Puyallup River, Skagit River, Snake River, Spokane River, Walla Walla River, Wishkah River, Yakima River, and Tacoma city waterway in Commencement Bay. These Special temperature designations are for the stream waters in the listed segment only. Temperature standards for all waters feeding that segment are as shown in the polygon coverage. This data set is a polygon coverage, and does not contain information on all surface waters listed in the WAC. All questions pertaining to temperature classification of surface waters in Washington must be clarified by referring to the WAC. |