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Show DRAFT DRAFT Modeling Great Salt Lake Salinity by Craig W. Miller, P. E., Norman E. Stauffer, Jr., Ph. D., and Kidd M. Waddell USGS and DNR have have worked together for many years to help analyze and solve GSL problems involving flooding and salinity. USGS created a model to simulate the dynamic hydrologic and hydraulic processes of the GSL. The current version of the model will be fiilly described in a USGS report which accounts for the the mass balance of water and salt in the north arm and the south arm, flow through the causeway fill, culverts, and breach; and pumping to the West Pond. The latest version was calibrated for the period from 1987 to 1999 and produces results that agree with historical records. The first model version created by the USGS for this purpose was documented by Waddell et. al. ( 1973). Schematics showing the general operation of the water and salt budget budgets calculated by the model are shown in figures 1 and 2. ill aJl^ k mM •••: •_ » 4Nfc. I « h' Mk: JHk'JHk"' TGt DdldnCB mm mi • - • WO! ' » ! ] •• ft AVN > QS - QN - EON:* PIN. + GIN •;:•-'•] rneas tineas. meas meas Figure 1. Great Salt Lake water balance. Almost all surface inflows entering Great Salt Lake, SIS in the graphic above, flow directly into the south arm. Surface flow entering the north arm is mostly unmeasured and requires estimation. After surface inflow, the next largest source of water for the lake is precipitation, followed by groundwater flow. The model also considers lake precipitation and evaporation. 361 |