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rivularis, and Sulix species and small herbaceous species such as smooth brome, timothy, wild rose, bedstraw, red top, canary reedgrass, and meadow fescue. Lower areas such as depressions and backwater oxbows are dominated by rushes (Eleociwris sp.), sedges (Curex sppJ, canary reedgtass, and smartweed. Upgmdient fields to the west of the River have not apparently received irsigation for some time and have extensive growth of musk thistle, and mustard species. Meadow fescue, Kentucky bluegrass, muttongrass, smooth brome, westem wheatgrass, California orchardgrass, sedges, and rushes, are typical throughout the lower river valley portion of the property. The terrace ridges are dominated by pinion pine, scrub oak, and shmbby species such as rabbit brush and basin big sagebmsh. 2.3 SOILS Soils across the project are of several types, aligning longitudinally to the property and the terrace ridgelines. Falfa clay loam, Arboles clay, and Simpatico loam are prominent above the westem terrace ridge. Zyme rock outcrop complex is mapped along the western terrace slope; however, gravel and alluvial deposits are prevalent along the upper and mid-slope portion of the terrace. Tenon loam is present in the lower portions of the property, extending across the Florida River water course. Ustic Torriorthents and Ustolic Haplargids occur exposed across the terrace slopes to the east of the river with Afioles clay prominent on the terrace flats. These soil units and distributions were confirmed in the field. (Soil distributions and types were taken from La Plata County Soil Survey) 24 HYDROLOGY Depth [o the water table, along the valley floor, is variable by elevation. Within the low alluvial plane paralleling the river the average water table is between l8 and 30 inches during the runoff in spring months and during the rainy season in mid-summer. Such high water tables make this area a high potential azea for wetlands and ponded areas, especialiy in back-water flooding areas within remnant oxbow features. Frequent flooding in the area has been reduced from historical levels by uses of the Florida for irrigation and due to the up-gradient Lemon reservoir dam. High flows in the Florida are generally experienced in late May and early June and is typically associated with increased releases from Lemon Dam in response to heavy snow-pack. Bankfull flows for the Florida are near 900 cfs and releases from Lemon in early 2005 exceeded this level for approximately a 4 week period. Low flows occur in the late fall and are approximately 50-60 cfs (CDWR 2005). The Florida River just above its confluence with the Animas is currently (August 23, 2005) at 54.3 cfs (CDWR 2005). Other influxes of hydrology in the area come from the extensive flood type irrigation throughout the area and above the terrace slopes. Topography is also a major hydrologic manipulating force. Small depressions will likely and frequently capture surface water influx from irrigation mnoff and precipitation and many are driven by the high water table levels in the spring and summer. ]rsigation influence is also likely to increase the groundwater recharge later into the season than would be witnessed in its absence. 2.5 CURRENT WETLANDS The USGS Gem Village, Colorado Quadrangle Map does not indicate any wetlands for this area. The National Wetlands Irrventory (NWI) data from the USFWS does not list any wetlands in this area. 3.0 DELINEATION 3. J ~NETHODS Off-site review-A routine method, as defined in the 1987 Corps of Engineers Wetland Delineation Manual was employed for the delineation procedures. Digital ortfiophotos (USGS lm resolution & 2003 1 ft. resolution), and the NRCS County Soil Sttrvey information was consulted prior to onsite inspections to identify any noticeable water features or topographical changes conducive to drainage and hydrologic Flows. y:[p5 &wwrys Fnim~wenhl Consu4mg, 0.C