Cost-equity considertions in salinity control in the Upper Colorado River Basin
American Geophysical Union
Salinity in the Colorado River Basin has been a serious concern for the past few decades and therefore, efforts have been underway to predict salinity generation and develop appropriate mitigation strategies. In addition to the physical processes, establishing the allocation of salinity control responsibilities among watersheds to meet the salinity control targets is important. For salinity control in the Upper Colorado River Basin, there are established water quality standards (given as TDS concentration) at three monitoring stations. Accordingly, total TDS load to be reduced in the basin has been set to meet the standards. In this paper, a practical framework to allocate salinity control responsibilities is developed considering cost-effectiveness, equity, and their trade-offs. Different allocation scenarios of salinity control responsibilities are estimated to meet salinity standards in irrigated lands of the Upper Colorado River Basin. The scenarios consist of simple ratio based on irrigated land area, minimizing total control cost, and maximizing equity among watersheds. Salinity control cost, possible maximum salt reduction of each watershed, irrigated land area, and net agricultural income are used to define equity measures. Simple ratio based on irrigated land area has relatively high total control cost, and even bad equity scores. Cost minimization scenario has definitely the lowest control cost, and relatively good equity. Among the four equity measures, optimization for equity of control costs results in similar allocation to cost minimization. Because the cost function is quadratic, cost minimization and optimization for equity of control costs tend to distribute the allocation of salt reduction equally. On the other hand, other scenarios tend to put high responsibilities into the high yield watersheds. The proposed framework allow decision-makers to allocate salinity control responsibilities based on the allocation method and trade-offs between equity and costs.
Keum, J. and Kaluarachchi, Jagath J., "Cost-equity considertions in salinity control in the Upper Colorado River Basin" (2012). Civil and Environmental Engineering Faculty Publications. Paper 1608.