Bear River Basin (Overview) HUC# 160101, 160201Basin Geography:
The Bear River Basin is located in the southwest corner of Wyoming. The Bear River originates in the Uinta mountains of Utah before flowing northward into Wyoming. The river flows across the Wyoming-Utah state line several times before flowing into Idaho and then eventually back into Utah and the Great Salt Lake. In Wyoming, the river flows through the city of Evanston and the town of Cokeville before flowing out of the state. The Smith's Fork enters the Bear as a major tributary in the north of the Basin delivering runoff from the Salt River Range. Bear River flows are subsequently stored downstream in Bear Lake through an off stream diversion in Idaho. Downstream demands are an increasing concern for Wyoming as Utah experiences growth and threatened fish species surrounding Bear Lake have become evident.
The Bear River drains approximately 1.5 percent (1,467 square miles) of the land area in Wyoming. The basin is characterized by mountainous terrain from which abundant winter snowfall feeds perennial streams. Woodruff Narrows and Sulphur Creek are two major Wyoming reservoirs which store spring runoff. Approximately 54,000 acres are irrigated with surface water within the Wyoming portion of the basin. Alluvial groundwater resources have adequate yields and are principally used for irrigation. Most valley wells exploit this shallow alluvium. A deeper high yield saturated aquifer also exists.
Water quality concerns have grown recently. Most surface water contaminants are human or livestock wastes. Sediment loading is also of concern in several tributaries as are nutrients such as phosphorous, which is evident in natural deposits.
Relevant Compacts and Decrees:
The Bear River Compact serves as the administrative mechanism between Wyoming, Utah and Idaho. The compact divides the three-state basin into three divisions. The Wyoming portion of the basin falls in the upper and central portions. The original 1958 compact was amended in 1980. Under the 1958 agreement, Wyoming was allocated 17,500 acre-ft of storage per year. The amended compact granted Wyoming an additional 35,000 acre-ft of storage, of which 13,000 acre-ft may be depleted annually.
The Bear River Compact sets conditions and requirements for emergency water situations. Included in these emergencies are situations where Bear Lake, in Idaho, falls below the 5911 ft level. A portion of the water allocated to Wyoming in the amended compact is not being used in current operations.
US Geological Survey. 1985. National Water Summary-Wyoming: Surface Water Resources, Water Supply Paper 2300. Washington D.C. pp. 498.
US Geological Survey. 1990. National Water Summary-Wyoming: Stream Water Quality, Water Supply Paper 2400. Washington D.C. pp. 573.
Bear River Commission. 1995. Eighth Biennial Report 1993-1994-Overview, Bountiful, Utah. pp. 7-10.
Wyoming Water Development Commission & Wyoming State Engineer's Office. 1996. Wyoming Water Planning: A Report for Updating the Process. Cheyenne, WY. pp.10
Wyoming State Engineer's Office. 1973. The Wyoming Framework Water Plan. Cheyenne, WY. pp. 220