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Show Water - Chemistry The " Water Chemistry" section addresses the overall salinity and ion concentrations of the water of GSL. Biological and other chemical water constituents are briefly discussed in the " Water Quality" and " Biology" sections. Based on internal and external scoping, the planning team has identified five major categories of issues related to water chemistry. The water chemistry and salinity differentials and trends are significant to the aquatic and avian biology of GSL and to the extraction of mineral salts from lake brines. The impacts of varying water chemistries and salinities to the wildlife and mineral industries of the lake are discussed in the " Biology" and " Minerals and Hydrocarbon" extraction sections, respectively. This section focuses on the physical and chemical aspects of GSL, factors influencing nutrient inputs and losses from the lake and the lake hydrologic processes. The planning team has identified the following lake water salinity and chemistry conditions and trends as relevant to lake management: • The continuation of separate and distinct salinity areas in GSL is an issue. • There is an apparent change in the exchange of salts between the north and south arms. This has resulted in the south arm being less saline than before the high water years for a given elevation. • There should be an investigation to determine if there are stable lake brine ion concentrations and isolation of quantities of soluble salts from the lake system. • There is a lack of an accurate accounting for the quantities and locations of salts in the lake system. • There is a lack of knowledge regarding nutrient chemistry and its influence on biological productivity in the lake. Separate Water Salinity Areas in the Great Salt Lake It is believed that, prior to construction of dikes, causeways and mineral extraction facilities in GSL, lake brines were similar in composition and concentration throughout the lake ( See Appendix I). Since the early 1900s, dikes and causeways have been constructed in GSL for a variety of purposes. Several of these inhibited the unrestricted movement of lake brines among large areas of the lake. Coupled with the fact that most of the freshwater inflow to the lake occurs on the eastern shore, distinct salinity conditions have developed in four main areas of GSL. From freshest to most saline, they are; Bear River Bay, Farmington Bay, the main body of the lake ( sometimes referred to as the " south arm" or Gilbert Bay) and Gunnison Bay, often referred to as the " north arm". Figure 8 shows the areas of salinity in GSL. Bear River Bay 41 |