ALLOCATION OF AUGMENTED WATER SUPPLY UNDER A PRIORITY WATER RIGHTS SYSTEM.

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 efficiency 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.