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Show 2.2.1 Model for water supply Water supply management models are tools for state and local water agencies in planning for the development of their areas water resources. The formulation presented considers a planning horizon ( eg. 20 years) composed of several planning periods ( eg. 5 years). The state of development at the beginning of each period is used for that whole period. Decisions on new development are made only at the beginning of each planning period. This structure requires optimization to be carried out sequentially, results from the previous planning period becoming initial conditions for the next period. Focusing on the groundwater management aspects of the water supply problem, stream- aquifer interaction will not be considered. Decisions on pumping rates and reservoir operation are required either monthly or by growing season. The complexity of modeling a stratified aquifer system is justified in the additional information provided. Water use agencies may be interested in exploiting shallow as we as deep aquifers, or interference between small, independent users of the shallow aquifer and local suppliers utilizing deep aquifers may be of concern. The site location for the initial period is shown in Figure 2.2. An existing reservoir is shown, additional surface water development at predetermined sites may be included in future planning periods. Points in the area where drawdown is of concern may include water agency boundaries or a reservoir- aquifer interface. / miriii> ituru> i> iii] u> nii>> ifni} i> iti! iiuint> trtunr> iti}> iiiiuifit> tr> t} irnuu > . . x Demand Area3 \ Peser- Demand Area 1 / ^ ^ voir p x Q9 X X < S • " ( ® L X 1 ® * Stream ® R - X- X-- X X X X Jt#*' X_- X :"* Demand Area 2 x © ® v ® X : ® \ x © x tmittiii Aquifer Boundary O Pumping Center Demand Area Boundary x Dravdovn Control Point Figure 2.2 Representation of site location for water supply model Objective Function The objective of the management model is to minimize the cost of supplying water to users from all sources, in this case reservoir, stream and aquifer. 15 |
