July 2013, Issue 73: Editor’s Notes

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Modifying Colorado River operations may be a low-cost, feasible way to augment water supplies, but is it politically palatable?

Last December, the U.S. Bureau of Reclamation completed the Colorado River Basin Water Supply and Demand Study. This 3-year study sets a new baseline for water planning in the Basin, incorporating input from states, tribes, environmental groups, and agencies. It concludes that, at the projected consumption rates, demand will exceed supply in the not-too-distant future. Furthermore, hydrologic modeling conducted under this study predicts that climate change will further strain already limited water supplies.

Over 100 options and strategies were evaluated as part of this study. They ranged from “hard-path” solutions emphasizing new supplies and infrastructure (importation, desalination, and reuse) to “soft-path” solutions focusing on demand management (water conservation, water transfers and exchanges, and systems operations). Each was evaluated in terms of water supply benefits, project cost and feasibility, and political palatability.

One option that ranked favorably in terms of cost and feasibility was modifying river operations. An example of this type of proposal, dubbed “Fill Mead First” (FMF) by the Glen Canyon Institute (GCI), may gain visibility after a recent analysis in The Water Report[1] concluded that it could be implemented within the legal framework of the Law of the River. Under FMF, Lake Mead would become the primary water storage and distribution facility for both the Upper and Lower Basins, and mostly natural runoff would flow through Glen Canyon Dam. Currently, Lake Powell and Lake Mead are managed jointly, with  “equalization” provisions to not only protect power generation and recreational uses but also to balance water supply and environmental needs. Under the proposal, FMF would maintain a minimum water level in Lake Powell, using excess capacity only for seasonal flow variations, flood control, and sediment distribution purposes. The GCI estimates that this would save up to 300,000 AF/yr by reducing bank-seepage and evaporation losses from Lake Powell. FMF also offers an added benefit — environmental restoration — because it would drain water from currently flooded areas in Glen Canyon and allow a more natural flow regime in the Grand Canyon.

Although possibly favorable from the perspective of net water supply, FMF will have a hard time passing the political palatability test. Power companies, states, tribes, and recreationalists may fear that FMF will compromise their interests. For example, Upper Basin power interests are unlikely to support this plan if it reduces benefits to customers of Glen Canyon power. Water interests are unlikely to support FMF if it increases the likelihood of a “compact call” (a situation under which the Upper Basin would have to curtail water use to meet the “75/10 requirement” of the Colorado River Compact).

The Water Report concludes that implementing FMF would require changes to several tenets of Colorado River operations, including the 1970 Long-Range Operating Criteria and the 2007 Interim Guidelines for joint reservoir operations. Although such changes fall under the sole authority of the Secretary of the Interior, they would certainly require buy-in from all basin states and stakeholders. Since the hurdles are more political than legal or technical, stakeholders will have to determine whether FMF is indeed worthwhile, in whole or in part.

FMF is just one of many ideas that will require thorough vetting before the Law of the River can be changed. Changes of this type — which mean deviating from the status quo — are generally motivated by physical or political stresses. The increasing likelihood of a shortage declaration in the next few years could be just the kind of stress to shift the current balance.

[1] L.J. McDonnell, #112, June 15, 2013

Juliet M. McKenna, MS, PG