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