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West Elk Mine
<br />with their headwaters near the peak of Mount Gunnison. Although several tributaries flow
<br />through the lease area, including South Prong, Horse Creek, and East Fork, the only tributary
<br />watersheds of Minnesota Creek that are partially located within the permit area are the Dry Fork
<br />of Minnesota Creek (Dry Fork) and Lick Creek, and the north fork of the S. Prong Creek which
<br />drains the extreme southern portion of the permit area.
<br />
<br />Table 8
<br />Characteristics of Lease Area Watersheds
<br /> Drainage Maximum Minimum Channel Channel
<br /> Area Elevation Elevation Length Slope
<br />Watershed' (mi) (ft) (ft) (mi) (%)
<br />D Fork lower 7.49 8,720 6,70 5.6 6.0
<br />Minnesota Creek lower 41.3 12,700 61200 11.5 6.9
<br />Lick Creek 1.85 9,730 7,630 2.8 12
<br />South Prong 3.27 12,390 7,380 2.2 18
<br />Horse Creek 1.75 12,390 7,830 3.5 19
<br />Dee Creek lower 4.68 12,180 7,200 4.4 11
<br />Box Canyon 0.88 8,480 6,120 1.2 16
<br />Sylvester Gulch middle 4.25 8,480 6,220 3.6 8.4
<br />Gribble Gulch lower 1.20 8,170 6,640 1.1 17
<br />
<br />Notes:
<br />1. Watershed names refer to gaged basins as shown on Map 34.
<br />2. Permanent gages are no longer installed on South Prong and Horse Creek.
<br />3. Permanent gages have not been installed on Box Canyon and Gribble Gulch.
<br />The Dry Fork receives much of its flow from the Deep Creek Ditch, an inter-basin diversion that
<br />enters the eastern boundary of the Dry Fork drainage basin where the flows are measured by the
<br />Upper Dry Fork gage. This additional flow allows the Dry Fork to flow several months after the
<br />end of snowrnelt runoff. It is MCC's opinion that without these supplemental flows the Dry
<br />Fork would be strictly ephemeral. However, because the currently available data does not
<br />specifically indicate whether the majority of Dry Fork is ephemeral, intermittent, or perennial,
<br />MCC will continue to monitor the flows through the Dry Fork flumes, the interbasin diversion
<br />operational data, and visually check the flows in the fall after water is no longer being diverted to
<br />Dry Fork to determine if the stream is ephemeral, intennittent, or perennial. After at least 3 years of
<br />observations, the permit application will be modified to include the conclusions made regarding the
<br />flow characteristics of the stream, based on the aforementioned. Based on available data, the
<br />average annual diversions for Deep Creek Ditch are approximately 1,000 acre-feet per year. The
<br />Deep Creek Ditch diverts flow from Little Gunnison Creek, a tributary to Coal Creek and ultimately
<br />the North Fork. As the ditch traverses across the upper portion of the Deep Creek watershed, it
<br />collects runoff from Deep Creek tributaries then enters at the headwaters of the Dry Fork.
<br />Generally, there are transit losses that will be experienced as Deep Creek Ditch transbasin diversion
<br />flow from the upper Dry Fork \ atersh: d into the lower Dry Fork watershed. Transit 'losses are
<br />commonly experienced in irrigation ditches and natural drainage channels. They are attrilDutable to:
<br />bank storage, infiltration losses, channel storage, and evapotranspiration. Due to the characteristics
<br />of the Dry Fork charnel in the upper watershed (e.g., dry channel for much of the year, cracked
<br />charnel bottom, significant chaimel erosion, wide channel with steep banks, no evidence of
<br />groundwater inflows to charnel and others), transit losses will be experienced.
<br />2.04-79 Revised Alovember• 2004 PR10, March 2006: Rev. April 2006 PRIO: Rev. May 2006 PRIG; Sep. 2007 PR12; Feb. 2008 PR12
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