What will it take to stabilize the Colorado River?

American Association for the Advancement of Science (AAAS) | July 21st, 2022

The Colorado River supplies water to more than 40 million inhabitants in the southwestern United States and northwestern Mexico. A basin-wide water supply crisis is occur

The Colorado River supplies water to more than 40 million inhabitants in the southwestern United States and northwestern Mexico. A basin-wide water supply crisis is occurring because of decreased watershed runoff caused by a warming climate and legal and water management policies that allow systematic overuse. By the end of 2022, combined storage in Lake Powell and Lake Mead, the two largest reservoirs in the United States, will have declined from 95% full in 2000 to approximately 25% full. If this “Millennium Drought” persists, then stabilizing reservoir levels to avoid severe outcomes will require reducing water use to match diminished runoff. With a process underway to renegotiate interstate and international agreements on consumptive uses of the river, we describe a promising new management approach based on combined storage of both reservoirs, rather than just Lake Mead as currently used, to trigger consumptive use reductions to the Lower Basin and Mexico.

Widespread drought-driven declines in streamflows and water quality in the Upper Colorado River Basin during 1998-2022

Nature Portfolio (Springer Nature) | September 14th, 2026

The cascading effects of meteorological droughts on river flows and water quality in mountainous regions are poorly understood. Using a data-driven framework, we studied

The cascading effects of meteorological droughts on river flows and water quality in mountainous regions are poorly understood. Using a data-driven framework, we studied drought impacts on streamflow, water temperature (WT), specific conductance (SC) in the Upper Colorado River Basin (1998-2022). Severe meteorological droughts in 2001-2002, 2012, 2018, 2020-2021 reduced annual streamflows by 15%, increased WT by 9% and SC by 5% relative to normal adjacent years. Declines were greatest in spring and summer, with reduced peak flows. Streamflow and SC recovered until 2018, after which successive droughts prolonged impacts, whereas WT effects were transient. Catchments with higher freshwater withdrawals, deciduous forest cover, air temperatures, residence times, finer soils had greater streamflow declines, while higher subsurface flows and infiltration enabled resilience. WT increases were associated with higher elevation, slopes, precipitation and lower agriculture, shrub cover. Open water and reservoirs mitigated SC increases. Thus, catchment attributes influence drought vulnerability in mountainous regions.

Wildfire and Drought: Impacts on wildfire planning, behavior, and effects

National Integrated Drought Information System | March 4th, 2016

The relationship between drought and wildfire can appear to be simple, but the drought and wildfire nexus encompasses a profusion of human and environmental impacts. Imag

The relationship between drought and wildfire can appear to be simple, but the drought and wildfire nexus encompasses a profusion of human and environmental impacts. Images of burning forests, neighborhoods, and “smoked out” communities are all now commonplace. The National Integrated Drought Information System, in partnership with NOAA’s Western Regional Climate Center (WRCC), the California Nevada Applications Program (CNAP, a NOAA Regional Integrated Science Applications team), the Desert Research Institute (DRI), and the National Drought Mitigation Center (NDMC), hosted the Integrating Drought Science and Information into Wildfire Management Workshop in Boise, Idaho on 21-22 October 2015.  The 22 participants in the workshop were invited as representatives of a broad spectrum of expertise including prescribed fire, wildland fire management, climatology, smoke and air quality, fuels management, fire behavior, drought, and policy. In this report, we present the opportunities and challenges the workshop participants identified and the impacts of drought on wildfire. The workshop also provided the opportunity to identify next steps in understanding and addressing drought impacts on wildfire.

Workshop on Improving Sub-Seasonal and Seasonal Precipitation Forecasting for Drought Preparedness

California Department of Water Resources (DWR) | October 15th, 2015

Skillful sub-seasonal (monthly) to seasonal (the water year) precipitation forecasting would support many facets of water management, providing lead time for preparing fo

Skillful sub-seasonal (monthly) to seasonal (the water year) precipitation forecasting would support many facets of water management, providing lead time for preparing for extreme events and allowing for more efficient operation of water infrastructure. Current forecast practices and scientific capabilities for making skillful forecasts beyond the weather time domain, however, are limited. Through a series of prior annual workshops on climate variability, climate extremes, and drought held by the Council and the California Department of Water Resources (CDWR), some possible opportunities for improving forecasting skill at a regional scale have been identified. The purpose of this May 2015 workshop was to develop a Western vision for improving monthly and seasonal precipitation forecasting, loosely modeled after the Council’s vision for an observing network for Western extreme precipitation. The analyses performed to understand patterns responsible for heavy precipitation events at a regional scale – such as atmospheric river storms or the Southwest monsoon -- also point out pathways to explore for improving forecasting of these events. The timing is ripe for efforts to improve monthly and seasonal forecasting. Drought in the West has called attention to the need for better information to support preparedness and response, and NOAA’s report on the California drought provides a focal point for followup actions. The National Weather Service (NWS) is reviewing approaches for developing experimental week three and week four outlooks. The National Research Council has convened a committee to develop a U.S. research agenda to advance subseasonal to seasonal forecasting.