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Affected Environment This chapter describes the environmental components (resources) of the project area that would be affected by the alternatives. In other words, this chapter describes the baseline conditions for those environmental components deemed to be affected by this project. The resources addressed in this chapter will be discussed in the same order as they are discussed in Chapter 1.4 (Issues Selected for Analysis) and Chapter 4 (Environmental Consequences). Watershed drainage function This property is located in the headwaters of Amazon Creek, one of the largest drainages flowing through Eugene. Water that enters this property from either rainfall or through culverts under Dillard Rd., flows along one of three waterways through the property. The three waterways converge at a depressional wetland at the lowest portion of the property. After that, water flows off the property into a culvert where it continues downstream until it outfalis into the main channel of Amazon Creek. The open waterways on this property have been partially destabilized by upstream developments including Dillard Road. Water is channeled into three culverts that flow under Dillard Road. Funneling flows in this manner has increased the quantity of water entering the waterways. Similarly, upstream gevelopments have increased the impervious surface of the landscape leading to more rapid runoff rates. Thus, the increased quantity and rate of runoff have combined to cause some increased erosion and incision along these three waterways. However, large sections of all three waterways appear stabilized. The entire creek system is vegetated with riparian vegetation and adjacent areas are vegetated with forested habitat. At the downstream end, the three waterways converge into a relatively flat depressional broadleaf wetland area where flow rates are slowed and deposition of sediments is likely. This wetland area is dominated by native species including slough sedge (Carex obnupta), an obligate wetland plant. Currently, the vegetated areas along the creek as well as the more upland vegetated areas are functioning to attenuate flows in the channels by intercepting rainfall. Similarly, the soil duff and topsoil areas are relatively permeable allowing significant infiltration to occur. Loss of vegetation, compaction of soils, or increases in impermeable surfaces would affect waterways by increasing flow rates and volumes, increasing erosion and incision, and destabilizing the streambed. Wildlife Habitat Wildlife habitat must have a variety of components to function properly including water, food, shelter, and travel corridors. All of these features are present on Dillard Hollow. The 38.4 acre property is dominated by mixed conifer forest habitat. Three creeks flow into a 2.4 acre depressional broadleaf wetland at the downstream end of the waterways. This wetland is dominated by Oregon ash (Fraxinus latifolia) and big -leaf maple (Acer macrophyllum). The southernmost waterway has a wide riparian forest dominated by big -leaf maple (Acer macrophyllum) and vine maple (Acer circinatum). The western, northern and eastern edges of the property are adjacent to developed areas which affect the function of travel corridors. However, the southern border of the property is contiguous with the Amazon Headwaters Open Space owned by the City of Eugene Parks and Open Space Division. This 226 acre park consists of similar habitat with several drainages, mixed conifer forests and depressional broadleaf wetlands. The Amazon Headwaters property is also contiguous with several other open space properties along the Ridgeline Park system. All of the wildlife species known to occur on Dillard Hollow also occur on the Amazon Headwaters property and adjacent properties many of which are also publicly owned.