The upper Rio Grande Basin, like much of the American Southwest, has been in significant drought with few periods of recovery since the early 2000s. The drought has strained water supplies and forced modifications to water supply operations in many basins. Hydros began development of a model of the Rio Grande Project for the New Mexico Interstate Stream Commission in 2007 to evaluate impacts of changes to the Project’s operations and accounting protocols stemming from new Project operating policies implemented by Reclamation. In 2013, Texas filed a complaint with the U.S Supreme Court alleging that New Mexico was in violation of the Rio Grande Compact of 1938. In 2017, Hydros was asked to provide litigation support to the State of New Mexico in this case.

The Rio Grande Project model developed by Hydros became the foundational tool in New Mexico’s arguments against the claims brought by Texas. The model was coupled with two groundwater models, one simulating groundwater use in the Hueco basin underlying irrigated lands in Texas and Mexico, and the other simulating groundwater use in the Rincon and Mesilla basins in New Mexico and parts of Texas. These models were used to evaluate a variety of historical, current, and hypothetical future conditions, including variations in hydrology, demands, and operational policies. The model simulated Project operations, including annual allocations of water to Project contractors, simulation of supplemental groundwater use, and the interaction of surface and ground water supplies resulting from the conjunctive use of the resource.

In late 2022, the parties in the case entered into a preliminary agreement to settle the case.  That agreement is currently before the Special Master and, subject to dismissal of any remaining issues or objections, awaiting approval by the Court.