Little Powder Watershed
Watershed Description
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The Little Powder River originates just north of the City of Gillette, Wyoming and flows into the Powder River near Broadus, Montana. The Little Powder River watershed consists of 1,297,045 acres, and its boundaries extend across Campbell County Wyoming, Crook County Wyoming, and Powder River County Montana. Campbell County, Wyoming contains an estimated 66.7% of the Little Powder watershed. The Little Powder River has been classified as a 2AB water way. Class 2AB water bodies are protected for the agriculture, recreation, drinking water, game fisheries, and other aquatic life. The Little Powder River is bounded on the east by the Belle Fourche and the Little Missouri River Watersheds and on the west by the Powder River Watershed. The Little Powder River Watershed consists of 1,297,045 acres. The basin relief is 1,870 feet and the channel length is 177 miles. Flowing northward, the Little Powder River enters the Powder River several miles northeast of Broadus, Montana.Surface ownership percentages in the Little Powder Watershed are roughly 3% Bankhead Jones, 9% BLM, 1% National Grasslands, 78% Private, and 6% State Lands USGS data indicates that perennial flow is common on the stream with only nine no flow records at the two primary sites monitored in the watershed since 1975. The USGS currently collects temperature and discharge data at the Little Powder River AB Dry Creek gage station 06324970, near Weston Wyoming. Click here to view the current conditions at the Little Powder River gage station.
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*Sub Watersheds in the Little Powder Watershed
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Water Quality
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In 2002, the Little Powder River was initially added to Wyoming’s section 303(d) List of threatened waterbodies. This stream was listed as threatened for contact recreation designated use impairment by fecal coliform (WDEQ, Feb. 2016). In 2006, the threatened status was elevated to “impaired” and the Little Powder River was added to Wyoming’s section 303(d) List, Table A, Impaired Waterbodies. The impaired segment of the Little Powder River extends from the Wyoming/Montana state line upstream to the confluence with Spring Creek. CCCD has monitored water quality and quantity data on the Little Powder River at 3 primary sites, at different intervals, since 2002. Prior to Little Powder River’s 303(d) listing, historical water quality/quantity data has been collected by the USGS since mid-1970.
In all waters designated for primary contact recreation, during the summer recreation season (May 1 through September 30). Concentrations of E.coli bacteria shall not exceed a geometric mean of 126 organisms per 100 milliliters during any consecutive 60-day period. (Wyoming Water Quality Rules and Regulations Chapter 1, Section 27) Recent monitoring completed by CCCD indicated that bacteria concentrations fluctuated greatly from the 2015 to the 2016 monitoring seasons. The 2015 monitoring seasons received above average precipitation, while the 2016 monitoring season was much hotter and dryer. The significant hydrological and meteorological variation between the 2015 and 2016 monitoring seasons, make it difficult to determine if water quality improvements were actually achieved. The severe drought conditions in 2016 corresponded to low E.coli concentrations, while the above average precipitation rates in 2015 corresponded to higher E.coli concentrations. |
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Projects and Reports
Little Powder River Watershed Plan, 2006The Little Powder River Watershed Steering Committee addresses concerns with fecal coliform and other water quality standards through a voluntary, landowner driven planning process. The Little Powder River Watershed Steering Committee will reconvene in 2018, to develop a Watershed Based Plan. If you are interested in participating on this steering committee, please contact the CCCD office
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Little Powder River E.coli Source Project
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