Abstract |
Economic impacts of alternative on-farm water management programs for controlling saline irrigation return flows are estimated. The study focuses on the Grand Valley in west central Colorado, an area thought to be representative of irrigation return flows problems in the Upper Colorado River Basin. Direct economic impacts, in terms of increased cost or reduced incomes, are estimated with linear programming models of representative farm situations. A regional interindustry model was developed to trace indirect economic impacts on related economic sectors in the three-county local trade area. Since the hydrologic-geologic relationships which govern salt pick-up in the study reach are not entirely understood, a correlation and regression analysis of water quality and quantity data was performed. This analysis attempted to distinguish salt contributions of natural origin from those due to irrigation, and to separate irrigation concentrations into components attributable to on-farm irrigation practices as compared to water distribution system losses. |