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boundary of the permit area. Map 102 shows the extent of alluvial deposits found <br />along Red Wash within the permit area, and to a point approximately 1/2 mile <br />upstream from where Red Wash enters the permit area. From this map, it appears the <br />deposits are approximately 800 feet in width. Based on this map, it appears no <br />alluvium was found along any of the tributary channels. The permittee did not <br />quantify the amount of land area which the alluvial deposits occupy; however, based <br />on Map 102, it appears the extent of the deposits exceeds several hundred acres within <br />the immediate vicinity of the permit area. The deposits also appear to extend further <br />upstream beyond the limit mapped by the petmittee. Channel incision in the alluvium <br />ranges from 5 to 30 feet. Actual thickness of the alluvium along Red Wash is <br />generally unknown, as only one well, Qal-2, was drilled within the drainage. This <br />well is located at the confluence of Red Wash and the White River. Bedrock was <br />reached at a depth of 21 feet. The information obtained from drilling operations along <br />the White River (inclusive of well Qal-2) indicate that the alluvium is up to 37 feet <br />thick in this area, with a maximum water table depth of approximately 11.5 feet. <br />Depths to water in the alluvium along Red Wash upstream from the confluence is also <br />unknown, again due to the absence of upstream wells in the alluvium. <br />Based on the extensiveness of unconsolidated alluvium along Red Wash and the <br />probable existence of water with the stream alluvium, the area qualif-ies for further <br />consideration as a potential alluvial valley floor. <br />Rarer Availability Criteria -Artificial Flood Irrigation <br />The permittee estimated the potential average annual water yield from the Red Wash <br />drainage basin using Gnrnsky's Formula (Gnrnsky 1908, Sellars, 1965; see <br />bibliography in permit application). The estimate indicates that an average of 2,090 <br />acre feet of water could be made available annually in Red Wash. This corresponds to <br />approximately 0.32 inches of nrnoff, which is about 3.5 percent of the annual <br />precipitation falling on the area. <br />Actual measurements of flow on Red Wash have been made using a crest stage gage <br />station located at the mouth of the basin. With the crest stage gage approach towards <br />stream monitoring, only peak flows which occur between monitoring intervals are <br />recorded. Flows which occur at less than the peak flow during any one monitoring <br />interval will not be recorded. The crest gage method is therefore useful for recording <br />peak events only; the method has limited application for determining duration of flow <br />and hence flow volumes which occur during the monitoring interval. <br />The results of the crest gage monitoring efforts on Red Wash indicate that flow is <br />almost entirely in response to snowmelt and storm rainfall events. A total of six <br />runoff events were recorded during the two year inventory period conducted by the <br />permittce. Events which occurred during the fall and summer months resulted from <br />thunderstorm activity; however, peak flows during the year were greatest during the <br />spring as a result of snowmelts. The largest event recorded for Red Wash during the <br />inventory period was 240 cfs, which was generated as a result of late winter snowmelt. <br />Because of the nature and intent of crest gage type flow monitoring, it has limited <br />25 <br />