APEX-MODFLOW: A New integrated model to simulate hydrological processes in watershed systems

APEX ( A gricultural P olicy/ E nvironmental e X tender) is an oft-used agroecosystem model but has limited use in groundwater-driven watersheds due to a simplistic representation of groundwater processes. This paper presents the linkage and flow MODFLOW into single modeling code. The mapping recharge, head, groundwater-surface water interactions are handled internally via subroutines. APEX-MODFLOW applied three United States for testing code accuracy hydrologic state variables fluxes: Animas River Watershed, Colorado New Mexico (3543 km 2 ); Price Utah (4886 Middle Bosque Texas (470 ). Whereas hydrology driven by snowmelt spring runoff, Watershed summer thunderstorms. can be used scenario analysis watersheds. • integrated links model. Model passes table elevation, gw-sw flux rates internally. Utah, Colorado, Texas, USA. results show importance including physically based flow.