The Colorado River Upper Initial Units Take Center Stage

Authors

• Eric Kuhn
• Anne Castle, University of Colorado, Boulder
• Jack Schmidt, Utah State University
• Kathryn Sorensen, Arizona State University
• Katherine Tara, University of New Mexico - Main Campus

Document Type

Preprint

Publication Date

10-6-2026

Abstract

In 1956, Congress authorized the Upper Initial Units—Flaming Gorge Reservoir,

Navajo Reservoir, and the Aspinall Unit (UIUs)—for a variety of water use

purposes in the Upper Colorado River Basin, including compliance with the

1922 Colorado River Compact (1922 Compact). The historical record is clear

that the primary reason these reservoirs exist is to satisfy the math of the 1922

Compact and the obligations it imposed on the Upper Division States

regarding flows at Lee Ferry.

Recommended Citation

Kuhn, Eric; Anne Castle; Jack Schmidt; Kathryn Sorensen; and Katherine Tara. "The Colorado River Upper Initial Units Take Center Stage." (2026). https://digitalrepository.unm.edu/uc_traveling_wilburys/14