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I I I I I I 1 I I I I I I 1--- I I I I I --- -' ES ENGINEERING.SCIENCE water table because direct stream linkages were not observed during field investigations. The banks of the small ponds are covered by willows, with some limited shallow-water shoreline areas supporting sedges and rushes. Spatial Distribution and Acreage Wetlands are found in floodplain and shoreline locations with saturated or flooded soils caused by either shallow water table or surface inundation. Such conditions occur in the Bear and Turkey Creek floodplains, along shorelines of the existing reservoir, and along two 11"n"med tributaries draining towards the northern side of the reservoir. Wetlands do not occur as inclusions or as isolated locations within the upland portions of the potential inundation area. Acreage distributions of wetland and riparian areas are summarized in Table 1. Most wetland acreage is located in the Bear Creek floodplain (approximately 26.6 acres within the maximum inundation area), followed by the Turkey Creek floodplain (11.5 acres), the Bear Creek Lake shoreline (2.3 acres), and two tributaries to the lake (0.9 acres). Additional wetland acreage occurs above the inundation elevation. Within the total area of maximum inundation (i.e., the area inundated by Scenario D), Bear Creek floodplain wetlands compose about 64.4 percent of the _ total wetlands, and Turkey Creek floodplain wetlands compose about 27.8 percent. -Lake ~hnreli"e wetlands and tributary wetlands comprise 5.6 and 2.2 percent, -Tespectively. Approximately 9.2 acres of riparian area occur within the maximum inundation area, with most of the total being about evenly split between the Bear Creek floodplain (about 4.4 acres) and the Turkey Creek floodplain (about 3.6 acres). A small area of 1.2 acres occurs as an isolated area south of the reservoir. The acreages and percentages of wetlands associated with the smaller inundation scenario are smaller, but the relative proportions among Bear Creek floodplain, Turkey Creek floodplain, lake shoreline, and tributary drainages remain the same. These proportions are listed in a later section. Wetland Quality and Functional Values Wetlands of Bear Creek and Turkey Creek floodplains and the two tributaries are considered to be of high value for several reasons, including wetland size, location, proximity to the reservoir, vegetation characteristics, surrounding land uses, and current functional values. The higher-rated functional values are judged to include wildlife habitat, sediment retention and stabilization, nutrient transformation, water quality, and production export The wetlands' value as wildlife habitat is one of the most notable functions of these areas. An important factor contnbuting to high wildlife habitat value is the high interspersion (i.e., mixing) of wetlands with riparian areas that occurs in both floodplains. This mixing of types combined with a high proportion of mature cottonwoods, willow thickets, streams, small ponds, small upland inclusions, and adjacent upland grasslands with relatively little human intrusion, creates a very attractive environment for many wildlife species. The close proximity of the lake combined with relatively stable water levels and more wetland and riparian areas -5- B16-3-3