Watering the Central Valley: modeling water flow and the affects of irrigation in the San Joaquin Valley, California using ParFlow

Abstract

The goal of this study was to develop a model that could incorporate complex subsurface hydrogeology as well as a complex surface topography and to complete a comparison study on the effects irrigation on terrestrial hydrology and energy budgets. This study uses ParFlow, an integrated hydrological model to determine regional flow, as well as to assess the effects that irrigation has on this system. This hydrologic model of the San Joaquin Valley of California was developed using static forcing based on climatology data and hourly distributed weather forcing data. The resulting model was composed of a domain of approximately 60,000 sq. km (269 by 219 km) at a 1km resolution run over a period of one water year using parallel processing. This work improves upon previous studies by applying a fully integrated hydrologic model on a finely discretized grid with an explicit treatment of both the valley and mountains.