WSP09806 - Laserfiche WebLink

Home Browse Search

~ GJ1 IV l\j be removed above Imperial Dam in order to reduce the pro- jected maximum salinity of 1005 mg/L TDS in 2010 at Imperial Dam to the criteria level of 879 mg/L. Budqet Constraints Model Reclamation, in association with Colorado State University, has developed a computer model to evaluate alternative program implementation scenarios. This model determines the optimal combination of projects and construction timing in order to meet salt load reduction goals at various invest- ment levels. The objective of this analysis is to develop a schedule which minimizes the total investment cost while removing sufficient salt load to maintain salinity standards in the Lower Basin. The annual and cumulative costs of program implementation are constrained within defined maxi- mum and minimum budget amounts (hence the model's name). A 4-year lag time has been set in the model to account for the delayed impact of Upper Basin salinity control projects due to storage and mixing in Lakes Powell and Mead. Appendix Table C-l shows that, to incorporate the 4-year lag, construction of Upper Basin projects begin 4 years before this salt load reduction is required in the Lower Basin. The model was designed to be a flexible tool for ongoing analysis of salinity control needs. Budget values and salt load reduction targets are user-defined and may be changed easily as new information becomes available. The values used in the present analysis are given in the Appendix (Table C-l). Other data required by the model are total remaining construction cost, annual OM&R cost, construction period, and expected annual salt load reduction for each project. Costs are defined to include the following items: Reclamation and BLM proiects - Advance planning costs incurred after project authorization - Construction costs allocated to salinity control - Interest during construction - Habitat replacement costs USDA proiects - Federal construction cost-share - Federal habitat replacement costs. 50