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Drought Response Operations Agreement

More than a decade ago, in response to five years of intense drought, the Department of the Interior worked with basin states, tribes and other basin stakeholders to adopt operating rules for the Glen Canyon and Hoover dams. Known as the 2007 Interim Guidelines, these operating regulations were passed to better coordinate the activities of Lakes Powell and Mead, promote water conservation, and provide objective rules for bottlenecks and reductions in water use in the lower basin in Arizona and Nevada. Since 2007, drought has persisted and other measures are needed, such as combining provisions that require lower water consumption with new incentives to save water to protect these reservoirs, which are essential to our environment and economy. While it is not clear what conditions the Upper Basin States Drought Plan contains or could include in terms of future discharges from initial units, it is clear that there is still a significant risk that Lake Powell will fall below the minimum pool level in the near future. The impact of new discharges could result in increased efforts and faster action by Colorado River Basin water managers to promote and implement water conservation measures throughout the watershed. For example, Reclamation has just announced a webinar scheduled for November 5, 2021 to examine the approach and reactive measures taken by Lower Basin States under the STC for managing a Lake Mead elevation that is expected to fall below 1,030 feet by July 2023. The cooperative planning model in Colorado River Basin planning efforts in the DCP and DROA appeared to have been implemented just in time as the West faces continuous and increasing climate change and drought. All the different stakeholders in the basin are struggling with drought levels in storage that have occurred faster than expected, with various triggering events moving quickly to take action. Proactive local planning should be expected for the next year of water 2022. In the lower basin, the STC agreements are accompanied by national agreements in Arizona and California for each lower basin state and related intergovernmental agreements between Arizona, California and Nevada that are necessary for the implementation of the STC. The implementation of the FADs would take place while representatives of the basin state, as well as tribes, NGOs and the public, worked to develop agreements on longer-term operations that would be adopted beyond 2026. Hydrology in the upper Colorado River basin, where 92% of the total input to the basin comes from, appears to be experiencing a modest respite during 2019. As of March 19, 2019, snowpack in the upper basin is 138% of the median, one of the highest snowpacks for this time of year since the onset of the drought, and seasonal runoff to Lake Powell is 133% of the average.

We remember that while hydrological conditions in the basin have improved this year, an above-average year of influx will not end the prolonged drought and significantly reduce the risks to the basin. Indeed, after a robust water year in 2011, the basin experienced exceptionally low snow cover and currents in 2012 and 2013. Due to hydrological uncertainty, it is still possible that Lakes Powell and Mead will fall to critical levels in the coming years. The basin States have now completed their drought plans and determined that national legislation will be needed to implement their plans immediately. As you will hear from the States, the purpose of the STC is simple. The goal is to reduce the risk of Colorado River reservoirs, especially the huge powell and mead reservoirs, sinking to extremely low altitudes. For example, and to put it in context, if Lake Mead were to sink to elevations below 1,020 feet of mean sea level, the remaining living storage at Lake Mead would be less than 6 million acres-feet at that time. In a normal year, the lower basin states consume 7.5 million acres feet and provide a total of 1.5 million acres feet to Mexico. According to the DROA, before the upper basin can complete its drought plan, it must consult with the states in the lower basin and obtain the approval of the secretary.

In particular, the States of the upper basin do not have to obtain the consent of the States of the lower basin, but only have to deal with the . Questions or concerns” of the Lower Basin States. Under the terms of other general agreements governing activities under the Colorado River Compact (i.e., the 2007 Interim Guidelines), the upper basin drought plan generally cannot extend beyond December 31, 2025, unless the initial units can recover (i.e., compensate for the loss of storage). At the end of the 2021 water year in October, the Colorado River basin remains in significant drought despite the summer monsoons and early fall rainfall in the west. This summer, the upper Colorado Basin states – Colorado, New Mexico, Utah and Wyoming – issued the first coordinated release of 181,000 acre-feet (AF) of water from three reservoirs on the Colorado River to increase storage supplies at Lake Powell. Although 181,000 FAs represents a relatively small amount of water compared to Existing Lake Powell Storage Reserves or Upper Basin Delivery Obligations under the Pact, the release marked the beginning of a new phase of critical planning around Compact compliance. With these water discharges completed by December 2021, all stakeholders are closely monitoring the Colorado River`s forecast and reclamation activities in the Colorado River Basin to prepare for the 2022 Water Year. The unprecedented 181,000 FAs of storage discharges into the Upper Colorado River Basin were made from the Flaming Gorge Reservoir (125,000 FAs), the Blue Mesa Reservoir (36,000 FAs) and the Navajo Reservoir (20,000 FAs) (collectively, the “Initial Units”) and will be carried out in accordance with the emergency provisions of a 2019 agreement between the Upper Basin States and the Secretary of the Interior. known as the Drought Response Operations Agreement (DROA). The DROA forecasts releases from initial units as the height of the Lake Powell reservoir approaches critical levels below which the Glen Canyon Dam can no longer produce hydroelectricity.

The DROA establishes a set of thresholds related to hydrological forecasts that, if exceeded, require upper basin states to take action to maintain the target elevation in Lake Powell. However, the DROA also includes provisions for emergency measures under which the Secretary, after consultation with the States of the upper basin, may order discharges from initial units independently of the States “if actual hydrology or operational experience shows an immediate need to protect the target altitude […]”. The publications published this year were made on the instructions of the Secretary in accordance with the emergency provisions of the DROA after consultation with the Upper and Lower Basin States and continued the long history of cooperative management between The Rehabilitation and the seven Basin States. Independent of the Secretary of State`s emergency agency, droa sets a set of thresholds related to hydrological forecasts that, in the event of exceedance, require states in the upper basin to take action to maintain the target elevation in Lake Powell. Those thresholds were exceeded this summer, so droa not only prompted the secretary to take emergency action, but also launched a broader planning effort by upper basin states to maintain the target elevation in Lake Powell. Although the upper basin has always met its 75 MAF supply obligation to the lower basin under the Colorado River Compact, the drought in the Colorado River basin has continued virtually unabated for two decades. For example, water storage in Lake Powell and Lake Mead – the two main savings accounts for the upper and lower basins under the Pact – has reached historic lows. Currently, water storage in Lake Powell accounts for less than 30% of capacity (approximately 7.2 MAF of 24.3 MAF). In December 2017, in my first public remarks as Commissioner for Recultivation, based on the ongoing historic drought, I called on the seven basin states and major river basin districts to complete their work on finalising drought contingency plans by the end of 2018.

During the development of faDs, States requested and received technical support from the Interior on issues such as the anticipated risk to the basin due to long-term drought. The Interior is proud to have worked with states, tribes, non-governmental organizations and other stakeholders in the basin on FADs. We look forward to continuing our work with states, tribes, NGOs, major water districts and Mexico in the implementation of FADs as soon as they come into effect. The DROA is one of the three main components that make up the larger Upper Drought Basin Contingency Plan, or “STC” for 2019 (the other two components are a weather modification program and a “demand management” program). The 181,000 FAs of storage discharges from the initial units, along with other significant changes made this summer — including the declaration of a “Level 1 deficiency” for the lower basin and a reduction in the amount of water normally released by Lake Powell for the year 2022 — underscore the impact of decades of drought in the Colorado River system. The DROA sets a target height of Lake Powell of 3,525 feet above sea level as the “target elevation” to minimize the risk that the upper basin will not be able to meet its obligations under the Colorado River Compact and to minimize the risk that Lake Powell storage will fall below the minimum level of the electric basin (i.e., 3,490 feet). .

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