Lower Colorado River

The Colorado is a river under siege. Except for unusually high flood years, virtually the entire flow of the Colorado is diverted and used before reaching the river's mouth at the Upper Gulf of California (Sea of Cortez). This has decimated its once-extensive delta and turned the mighty river into a trickle. Even in this degraded state, the remaining delta still comprises the largest and most critical desert wetland in North America. There are solutions to revive the river and delta, including efforts like the Laguna Reach Restoration, but unless we step up our efforts to protect these precious places and reduce the water we take, the river and delta will suffer irreparable harm.

What’s the best way forward? Recognizing the importance of the delta, and improving the efficiency of the many users who draw water from the Colorado can cut waste and free up new supply. In turn, this water could once again flow through the desiccated delta, to improve and maintain a substantial area of critical habitat. These strategies are described in “The Sustainable Use of Water in the Lower Colorado River Basin,” a Pacific Institute report published in 1996 (available only in print) and in a range of comments, letters, and articles we have written.

The long-term goal of the project is the preservation and rehabilitation of the remnant Colorado River delta, which we define as the riparian corridor downstream of Morelos Dam, the Cienega de Santa Clara, and several other smaller drainage-fed wetlands in Mexico. Preserving these areas ultimately will require a dedicated supply of water for the environment.  Achieving such a goal requires a series of intermediate steps, to address the host of ecological and institutional questions that remain.   

TThe Colorado River's delta and estuary are at risk. A series of management decisions, growing demand on an over-allocated resource, and the on-going drought in the basin create pressure to squeeze every drop out of the river before it reaches its delta. Recent actions, most notably the Drop 2 Storage Reservoir Project and the new shortage guidelines for the Colorado River (see the NGO proposal and the Bureau of Reclamation's Management Strategies document), could significantly degrade the remnant delta, by further decreasing the amount of water that flows down the river. We can set this mighty river on a course to better health – but only if we have the will to confront our past mistakes and the vision to craft a more sustainable future.

Laguna Reach Restoration Effort

Reports, comments and workshop proceedings on the lower Colorado River:

[2/15/07] Institute Comments on Drop 2 Reservoir Project

[7/05] Colorado River Lower Basin Shortage Proposal

[9/01] Report: "Missing Water: Report and Article Examine Water in the Colorado River Delta"

[01] MJ Cohen, C Henges-Jeck, and G Castillo-Moreno: A preliminary water balance for the Colorado River delta, 1992-1998 (Journal of Arid Environments 49:35-48 (PDF)

[9/00] Pacific Institute Comments on the Colorado River Interim Surplus Criteria DEIS (PDF)

Bureau of Reclamation Modeling of Pacific Institute Interim Surplus Criteria Proposal (PDF )

Colorado River Surplus Criteria Proposal

[11/18/99] Proceedings of the "Water Issues in the Colorado River Basin Border Region and the Salton Sea" workshop (PDF file) Spanish Translation