Estimated inflow and evaporation for Great Salt Lake, Utah, 1931-76, with revised model for evaluating the effects of dikes on the water and salt balance of the lake

K.M. Waddell; J.D. Barton

doi:10.3133/ofr79258

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Estimated inflow and evaporation for Great Salt Lake, Utah, 1931-76, with revised model for evaluating the effects of dikes on the water and salt balance of the lake

K.M. Waddell·J.D. Barton

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Abstract

A water budget for Great Salt Lake, Utah, was computed with 1-month intervals for the 46-year period of 1931-76. This budget updates previous computations for 1931-73, The updating was made on the basis of additional data collected during 1974-76. The storage change ( Δ S) during each month was computed from a budget of surface inflow (Is), ground-water inflow (Ig), precipitation on the lake surface (Ip), a calibration parameter (Ium) representing the net deficit between the estimated net inflows and the observed net inflows as computed from the observed altitude hydrograph, and outflow from evaporation (Oe), where Δ S= Is + Ig + Ip+ Ium - Oe. Based on additional pan-evaporation data collected at six sites around the perimeter of the lake, estimates of evaporation rates were reduced about 8 percent. The annual evaporation ranged from about 2.1 to 3.9 million acre-feet (2,600 to 4,800 cubic hectometers) and averaged 2.9 million acre-feet (3,576 cubic hectometers). Based on addie6nal surface-inflow data collected during 1974-76, the annual surface inflow to the lake for 1931-76 ranged from 705,200 (1934) to 3,767,000 (1971) acre-feet (870 to 4,645 cubic hectometers) and averaged 1,926,000 acre-feet (2,375 cubic hectometers). No changes were made to the 1931-73 estimates of precipitation (Ip) on the lake surface or to the estimate of ground-water inflow (Ig). These averaged 870,000 and 75,000 acre-feet (1,072 and 92.5 cubic hectometers) per year, respectively. The total annual inflow to Great Salt Lake during 1931-76 (Is + Ig + Ip+ Ium) ranged from about 1.3 (1961) to 5.0 (1971 and 1975) million acre-feet (1,603 to 6,165 cubic hectometers) and averaged 2.9 million acre-feet (3,575 cubic hectometers). Some minor revisions were made to the digital-computer model used to compute the water and salt balance for the Great Salt Lake. Most revisions involved adaption to the longer base period of 1931-76 and revision of the water budget as a result of changes in estimates of evaporation and surface inflow.

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Source-reported bounding extent: 40.61812224225511° to 41.740577910570785° latitude; -113.15093994140625° to -111.86279296875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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K.M. Waddell, J.D. Barton. 1978. Estimated inflow and evaporation for Great Salt Lake, Utah, 1931-76, with revised model for evaluating the effects of dikes on the water and salt balance of the lake. https://doi.org/10.3133/ofr79258

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