A conjunctive use model for the Tule River groundwater basin in the San Joaquin Valley, California

摘要

A conjunctive use model of the Tule River basin, California, USA, has been developed. We present the conceptual model of the basin hydrology and hydrogeology, and a description of the model components consisting of geographical information system (GIS)-based surface water and land-atmosphere interface and unsaturated zone (LAIUZ) models, and a GIS-linked groundwater flow model. The surface water model computes surface water allocations to each district and aquifer recharge from the major channels. For each land unit, LAIUZ computes the water budgets of the soil root and deep vadose zones, allotment of delivered surface water, pumpage required to meet the balance of its applied water demand, and aquifer recharge from surface applied water. The groundwater flow model computes groundwater levels in response to pumping and recharge. Crop consumptive use is adjusted to match the modelled basin hydrological budget to the measured one for an error of less than 1% annually.