Taos regional groundwater flow model
— P. Burck, P. Barroll, A. core, and D. Rappuhn

The New Mexico Office of the State Engineer Hydrology Bureau has developed a regional, 7-layer, groundwater flow model of the Taos Valley, New Mexico using MODFLOW-2000. This model was designed and developed together with the Taos Technical Committee, a team of experts in hydrology and geology, with many years of experience in the Taos area, and in conjunction with a U. S. Bureau of Reclamation (BOR) surface water model. Results from recent hydrogeologic investigations are incorporated, including deep drilling and hydrologic testing sponsored by the BOR, and the latest geologic mapping by the New Mexico Bureau of Geology and Mineral Resources. The model simulates groundwater flow in about 3000 ft of alluvial and volcanic materials, and is designed to estimate aquifer drawdowns and depletion effects to the Rio Grande, its tributaries and springs. The groundwater model serves two primary functions: first, as a tool to administer water rights, and second, to evaluate scenarios in settlement negotiations in an on-going water rights adjudication. This model simulates key hydrologic processes including natural recharge, irrigation seepage, evapotranspiration, and aquifer interaction with the Rio Grande and its tributaries and Buffalo Pasture Springs. Geologic strata represented in the model include Quaternary alluvial fan deposits, Tertiary Servilleta Basalt flows, and Tertiary Santa Fe Group sediments. The model simulates heads and groundwater discharges reasonably well, and captures major groundwater features such as large downward vertical gradients, thus allowing the interaction of the shallow and deep aquifer systems to be well simulated.