OCR Text |
Show although groundwater is fully appropriatedin Salt Lake County, it is largely underutilized. Economic measures suggest that groundwater should be developed prior to local surface water supplies. Jurisdictional and water quality issues do however curtail the efficient development of the local groundwater resource. 1.1 Study Objectives The formal objectives of the study were to develop efficient optimization models for the analysis of reservoir and groundwater development and operation. Importance was given to considerations of water rights and water quality, multiple uses for reservoirs, factors relevant to metropolitan water agencies, and to regional regulatory authorities as well as yield reliability. An analysis of the literature on optimization models for water use directed the focus towards the following issues: ( 1) Efficient models are needed for selecting between candidate reservoir sites, sizing the reservoirs considering multiple yields for municipal and industrial use, irrigation, hydropower generation, flood control and recreation. Simple reservoir operation rules that focused on delivering yields with specified reliability to correspond to typical water supply contracts were considered relevant to this study. Further, these developments should be in a framework that allows the incorporation of increased groundwater use in the system, either as an alternative to, or in conjunction with the releases from the proposed reservoirs. Chapter 5 presents the development of a reservoir screening model that addresses these issues. Chapter 7 presents the extension of this model to consider groundwater use. ( 2) Optimal utilization of existing reservoir facilities implies that the maximum sustainable yields be generated with specified reliabilities. There is a vast body of literature on optimal reservoir operation. Consequently, the objective was to select a general formulation for reservoir operation optimization, that was consistent with the first objective stated above, and was flexible enough to be generalized to consider ground and surface water conjunctive use, in the context of sustaining reliable yields. A candidate formulation that has simplicity and robustness as its attributes was selected. This formulation is reviewed and extended to multiple yields and reservoirs, and to consider groundwater in Chapter 6. ( 3) Models for groundwater management that were reviewed appeared to lack a focus on metropolitan water use where jurisdictional issues between competing water agencies and preservation of ground water quality are matters of serious concern. The development of a groundwater management model with an economic objective, adequate detail in representation of the aquifer system, considerations for both spatial and temporal variability of demand and supply, and constraints for drawdown control, preservation of the regional water rights structure and water quality maintenance was deemed necessary. The capability to model confined and/ or stratified aquifer systems was considered important. Chapter 2 presents a general formulation that is appropriate for the analysis of stratified aquifer systems. Chapter 3 presents a model for the least cost management of a groundwater system under the above considerations. ( 4) Water rights and water quality maintenance criteria often make the determination of the optimal or maximum developable yield of an aquifer system difficult. An optimization model for such determinations in the context of the same modeling criteria as in the third objective listed above was developed. This development is presented in Chapter 4. ( 5) Salt Lake County has been faced with rather complex issues and difficult choices in 2 |