Allocation of Augmented Water Supply Under a Priority Water Rights System

Abstract

A generalized network flow model has been developed to simulate the allocation of additional water supplies in a river basin with observance of the prior appropriation doctrine of water rights and other legal requirements such as interstate compact agreements. The computer model, called MODSIMR, is capable of simulating complex river basin morphology while incorporating a relational data base management system for efficiently accessing prioritized water rights. Program MODSIMR is a generalized model designed to be applicable to a wide variety of river basins operating under an appropriative water rights system. As a demonstration of its usage, MODSIMR was applied to the Rio Grande Basin of Colorado, New Mexico, and Texas for predicting allocation and use of increased runoff from simulated silvicultural activities on the Rio Grande National Forest. Results indicate that under the current institutional framework, increased runoff would primarily be allocated to agricultural users in Colorado. Computer results also showed the potential value to Colorado of the Closed Basin Project in the San Luis Valley and the possibility of determining optimal pumping schemes for the Project using MODSIMR. Program MODSIMR will be useful in future economic studies to determine the benefits of the augmented water supply under various water use scenarios.