Reclamation modifies monthly water releases from Lake Powell to protect reservoir’s critical elevations
SALT LAKE CITY – The Bureau of Reclamation began monthly operational adjustments at Glen Canyon Dam on Jan. 1, taking initial steps to protect the reservoir’s target elevation of 3,525 feet. As of Jan. 5, Lake Powell’s water surface elevation measured 3,536 feet, just 11 feet above the target elevation. Without the changes to monthly water releases, the reservoir’s elevation was projected to steadily decline below the target elevation through the winter months. The adjusted releases are designed to help protect critical elevations at Lake Powell until spring runoff materializes.
The monthly volume of water released from Glen Canyon Dam is being adjusted to hold back 350 thousand acre-feet (kaf) of water in Lake Powell from January to April when inflow to the reservoir is low. The same amount of water (350 kaf) will then be released to Lake Mead between June and September after the spring runoff occurs. The annual volume of water released from Glen Canyon Dam is unchanged by these operational adjustments.
“Under the Drought Response Operations Agreement, making these monthly operational adjustments at Glen Canyon Dam is essential to protect Lake Powell from dropping to critically low elevation levels in the weeks and months ahead,” said Reclamation’s Upper Colorado Basin Regional Director Wayne Pullan. “Although the basin had substantial snowstorms in December, we don’t know what lies ahead and must do all we can now to protect Lake Powell’s elevation.”
The modified release pattern was put into action after Reclamation met with basin partners including the basin states, Tribes, federal agencies, non-governmental organizations and water managers to discuss the purpose and need to shift the delivery schedule of water.
Water year 2022 got off to a promising start in the Colorado River Basin with a wetter-than-normal October, but it was followed by the second-driest November on record and resulted in a loss of 1.5 million acre-feet of inflow for Lake Powell compared to the previous month’s projections. December projections showed the reservoir dropping below the target elevation of 3,525 feet as early as February 2022. As defined in the Drought Response Operations Agreement, the target elevation provides a sufficient buffer to allow for response actions to prevent Lake Powell from dropping below the minimum power pool elevation of 3,490 feet, the lowest elevation that Glen Canyon Dam can generate hydropower.
While the basin recently experienced substantial snowpack, critically low reservoir levels coupled with uncertainty about future snowpack and observed spring inflow necessitate action. The modified release pattern for Glen Canyon Dam is as follows:
Reclamation is closely monitoring the basin’s hydrology and will release updated projections later this month. The modified release pattern may be further adjusted, if needed, in response to changing hydrologic conditions. The operational adjustments are consistent with the dam’s Long-term Experimental and Management Plan Record of Decision (LTEMP ROD) and will not impact operating tiers or annual release volumes at Lake Powell or Lake Mead. Only the monthly volumes are being adjusted; the annual release volume of 7.48 million acre-feet for water year 2022 (October 1, 2021 – September 30, 2022) will remain the same.
If future projections indicate the monthly adjustments are insufficient to protect Lake Powell’s elevation, Reclamation will again consider additional water releases from the Colorado River Storage Project initial units of Flaming Gorge, Blue Mesa and Navajo reservoirs. Meanwhile, Reclamation and the Upper Basin states continue to work on a Drought Response Operations Plan and expect to have it completed in April 2022.
“The plans adopted in previous years, including the 2007 Interim Guidelines and the Drought Contingency and Binational Water Scarcity Contingency plans, along with voluntary actions, have helped sustain the Colorado River System through the current 22-year-long drought,” said Reclamation’s Lower Colorado Basin Regional Director Jaci Gould. “We’ll continue to work with our basin partners in the future in the same collaborative spirit we have demonstrated in the past.”
The recently enacted Bipartisan Infrastructure Law provides the resources to back up Reclamation’s commitment to collaboration, with historic investments in water and drought resilience. Reclamation is working with its partners in the West in the transparent implementation of this law to meet the need for long-term adaptation for drought and a changing climate. For more information on the Infrastructure Law and Reclamation’s implementation, please visit our website at usbr.gov/BIL.