Economic Gains from Groundwater Management in California and Use of Remote Sensing

Abstract:

In California, groundwater is the swing resource for agriculture during drought. The availability of groundwater will drive some inevitable changes in the state’s water management, including more competition for water with ecosystem and urban water uses, continuous overdraft during dry years and the continued lowering of water tables which increase pumping costs and reduce groundwater pumping capacity. In this study we connect SWAP, an economic model for agricultural production and water use in California and C2VISIM the California Department of Water Resources groundwater model for the California's Central Valley. We examine dynamically the economic costs of pumping groundwater replacement during drought and the potential loss of pumping capacity as groundwater levels drop. We consider a three year drought continuing from 2014. Some areas in the California's Central Valley may suffer from a deeper water table and loss of some pumping capacity. Places without access to groundwater and uncertain surface water deliveries during drought are the most economically vulnerable in terms of crop revenues, household income and employment. This is the case of the Tulare Lake Basin that heavily relies on water imported from the Sacramento-San Joaquin Delta. Use of remote sensing information to estimate agricultural idle land between 2014 and 2014 confirms this finding. Results also point to the potential of a portfolio approach for agriculture, in which the crop mix and conservation practices may play a substantial role.