The primary purpose of the URGWOM is to facilitate more efficient and effective accounting and management of water in the Upper Rio Grande Basin. Historically, water of the Rio Grande has been used primarily for crop irrigation; however, rapid population growth in the Basin and urbanization in many areas has resulted in increasing and diversifying demands on the hydrologic system. Water management decisions must account for a board range of issues including flood control, irrigation demands, transmountain diversions, the Rio Grande Compact, municipal and industrial demands, Native American water rights, Endangered Species Act compliance, and recreational uses. As the wide range of water demands grow in the face of an inherently variable, and limited water supply, higher levels of precision and reliability in water accounting and forecasting are required.

A fundamental service provided by computational modeling with URGWOM is providing assistance to water managers in delivering supplies to all entitled water users on time, in the desired quantities, and with minimum conflict between users with particular focus on deliveries, exchanges, and leases of San Juan-Chama Project water. URGWOM, fed by automated data collection, provides accurate and up-to-date water accounting and reporting in support of this need.  URGWOM provides the community of water managers and users with a clear, consistent, and common set of data to formulate, evaluate, and support decisions.

Water accounting with URGWOM is used to track the status of water for Compact deliveries, international treaty obligations, Native American water rights, and more.  Additional water accounting procedures are used to calculate the Otowi Index Supply so that the imported San Juan-Chama Project water is not included in calculations of downstream delivery obligations for Rio Grande Compact purposes.

Water is stored annually in El Vado Reservoir to ensure the prior and paramount water rights of 8,847 acres of the Six Middle Rio Grande Pueblos. This right is provided under Section 11 of the March 17, 1980 agreement between the Secretary of the Interior and the Middle Rio Grande Conservancy District (MRGCD). Accounting procedures are needed in the model to differentiate this water from other native water and the San Juan-Chama Project water in the system.

Several of the major metropolitan areas in the Rio Grande Basin have shifted to conjunctive use of their available water resources. This water use strategy allows municipal water managers to meet increasing water demand by using both groundwater and surface water supplies. These conjunctive use strategies require detailed and reliable accounting to ensure that groundwater pumping effects are offset by reservoir releases that keep the river whole for downstream users. These changes impact the needs for modeling with URGWOM.