A warmer drought and structural overuse have consumed the reservoir buffer built for seven US states and Mexico.
Powered byTERRA 2100Historical drought evidence desk
When rivers run short
Four drought histories connected to measured water records, peer-reviewed research, dated reporting and an explicit recovery test.
- Cases
- 4 river regions
- Timeline
- 24 evidence scenes
- Downloads
- 25 source datasets
- Checked
- 18 August 2026
Southwestern North America
Colorado River, Lake Powell and Lake Mead
2000-present, with records back to 800 CE
Recovery statusNo basin recovery
Combined storage must rise across multiple water years while consumptive use falls enough to stop drawing down the buffer.
42%of 2000-2021 drought severity attributed to human-caused climate trendsWilliams, Cook and Smerdon, 2022
5.24 MAFLake Powell storage on 17 August 2026Observed or official record
6.96 MAFLake Mead storage on 17 August 2026Observed or official record
74%of direct human consumption used by irrigated agricultureRichter et al., 2024
Less precipitation matters, but warming also dries soils, raises plant demand and reduces the share of snowmelt that reaches the river. Legal demand remained above the river's twenty-first-century supply.
Wet 2023 snow briefly lifted storage. By August 2026, both Lake Mead and Lake Powell had set new record lows. A weather rebound did not become system recovery.
Playable chronology
Move through the evidence
Tree rings establish the long baseline
A soil-moisture reconstruction extends the comparison through more than twelve centuries, far beyond the short instrumental record.
Observed series
The reservoir buffer since 2000
Year-end observed storage, million acre-feet. 2026 uses the latest available daily value.
Loading observed series...
Research
- 2022Rapid intensification of the emerging southwestern North American megadrought in 2020-2021Paper
Williams, Cook and Smerdon. Nature Climate Change 12, 232-234
- 2017The twenty-first century Colorado River hot drought and implications for the futurePaper
Udall and Overpeck. Water Resources Research 53, 2404-2418
- 2024New water accounting reveals why the Colorado River no longer reaches the seaPaper
Richter et al.. Communications Earth & Environment 5, 134
Reporting and recovery updates
- Lake Powell hits a record low
The second major reservoir reached a new low one week after Lake Mead.
Associated Press - Lake Mead falls below its 2022 record
The report connects record-low storage with warming, drought and long-running overuse.
Associated Press - Emergency water is moved toward Lake Powell
Upstream releases protect hydropower at Powell while reducing buffers elsewhere.
Associated Press
Open data library
Download the underlying records
Local snapshots are marked. All other links go to the publisher's file or data portal.
DatasetCoverageFormatAccess
ColoradoLake Mead daily storageUS Bureau of Reclamation
1937-2026, dailyCSVDownload snapshotObserved storage in acre-feet. Provisional values may be revised.
ColoradoLake Mead daily elevationUS Bureau of Reclamation
1937-2026, dailyCSVDownload snapshotObserved pool elevation in feet.
ColoradoLake Powell daily storageUS Bureau of Reclamation
1963-2026, dailyCSVDownload snapshotObserved storage in acre-feet. Provisional values may be revised.
ColoradoLake Powell daily elevationUS Bureau of Reclamation
1963-2026, dailyCSVDownload snapshotObserved pool elevation in feet.
ColoradoLake Powell daily inflowUS Bureau of Reclamation
1963-2026, dailyCSVOpen datasetDaily average inflow. Open at source for the latest revision.
ColoradoLake Powell unregulated inflowUS Bureau of Reclamation
1963-2026, dailyCSVOpen datasetModeled inflow without upstream regulation effects.
ColoradoLake Powell total releaseUS Bureau of Reclamation
1963-2026, dailyCSVOpen datasetDaily release through Glen Canyon Dam.
ColoradoLake Powell evaporationUS Bureau of Reclamation
Operational recordCSVOpen datasetReservoir evaporation record.
Central ChileCAMELS-CL catchment attributesCR2 and PANGAEA
516 Chilean catchmentsZIP / CSVDownload snapshotClimate, hydrology, land cover, geology and human intervention attributes. CC BY 4.0.
Central ChileCAMELS-CL observed streamflowCR2 and PANGAEA
516 gauges, dailyZIP / CSVOpen datasetObserved streamflow in cubic metres per second.
Central ChileCAMELS-CL area-normalised streamflowCR2 and PANGAEA
516 gauges, dailyZIP / CSVOpen datasetObserved streamflow expressed as basin-depth equivalent.
Central ChileCAMELS-CL CR2MET precipitationCR2 and PANGAEA
Chile catchments, dailyZIP / CSVOpen datasetCatchment-mean precipitation from CR2MET.
Central ChileCAMELS-CL CHIRPS precipitationCR2 and PANGAEA
Chile catchments, dailyZIP / CSVOpen datasetIndependent satellite and gauge precipitation product.
Central ChileCAMELS-CL mean temperatureCR2 and PANGAEA
Chile catchments, dailyZIP / CSVOpen datasetCatchment-mean daily air temperature.
Central ChileCAMELS-CL snow water equivalentCR2 and PANGAEA
Chile catchments, dailyZIP / CSVOpen datasetBasin snow-water equivalent derived from the UCLA reanalysis.
SahelSahel Rainfall IndexNOAA Physical Sciences Laboratory
1901-2017, monthlyCSVDownload snapshotArea-averaged precipitation for 20-8N, 20W-10E. Static research series.
SahelSahel Rainfall IndexNOAA Physical Sciences Laboratory
1901-2017, monthlyNetCDFOpen datasetMachine-readable gridded-science format for the same index.
SahelCHIRPS rainfallClimate Hazards Center
1981-present, daily and monthlyGeoTIFF / NetCDFOpen datasetHigh-resolution satellite and station rainfall for drought monitoring.
SahelGPCC Full Data MonthlyGlobal Precipitation Climatology Centre
1891-present, monthlyNetCDFOpen datasetGauge-based global precipitation analysis used in long-term Sahel research.
SahelGlobal Surface WaterEuropean Commission Joint Research Centre
1984-2024GeoTIFF / Earth EngineOpen datasetSatellite water occurrence and change, useful for Lake Chad and floodplain recovery.
Murray-DarlingCAMELS-AUS catchment attributesUniversity of Melbourne and Zenodo
561 Australian catchmentsCSVDownload snapshotMaster table of hydrology, climate, landscape and uncertainty attributes. CC BY.
Murray-DarlingCAMELS-AUS v2 streamflowUniversity of Melbourne and Zenodo
561 catchments through 2022ZIP / CSVOpen datasetDaily observed streamflow with quality information.
Murray-DarlingCAMELS-AUS v2 hydrometeorologyUniversity of Melbourne and Zenodo
561 catchments through 2022ZIP / CSVOpen datasetDaily precipitation, temperature, evaporation and related forcing data.
Murray-DarlingWater Data OnlineAustralian Bureau of Meteorology
About 6,000 stationsWaterML / station downloadsOpen datasetCurrent and historical river level, discharge, storage, rainfall and water quality.
Murray-DarlingAustralian Water OutlookAustralian Bureau of Meteorology
1911-present plus projectionsCSV / NetCDFOpen datasetHistoric and projected runoff, soil moisture, rainfall and evapotranspiration.