High Plains · NE, KS, TX, OK, CO, NM, WY, SD
Ogallala (High Plains) Aquifer
Is the Ogallala Aquifer running out of water?
Ogallala (High Plains) Aquifer serves about 2.5 million people and underpins roughly $35B of agriculture across NE, KS, TX, OK, CO, NM, WY, SD. This model puts its probability of reaching crisis conditions at 0.0% by 2100 (95% CI 0.0%–0.008%), making it stable at the aquifer-average level, which hides sub-regional stress. No expected crisis year is produced at the aquifer-average level. Measured water levels are falling about 0.96 ft/yr.
Key figures
| Crisis probability by 2040 | 0.0% |
|---|---|
| Crisis probability by 2060 | 0.0% |
| Crisis probability by 2100 | 0.0% (95% CI 0.0%–0.008%) |
| Expected crisis year | Not reached in model |
| Observed decline rate | 0.9588 ft/yr |
| Latest observed level | 41.89 (2025) |
| Year-to-year volatility | 6.456 |
| Drought persistence φ (AR(1)) | 0.7804 |
| Population served | 2.5M |
| Agricultural value | $35B |
| Modelled annual damage at crisis | $11.75B |
How to read these numbers
Crisis probabilities are modelled, not measured: 100,000 Monte Carlo paths per aquifer combining AR(1) drought persistence with CMIP6 warming and demand-supply coupling. Observed decline rates and water levels are measured from USGS monitoring wells. A low aquifer-average probability does not mean local wells are safe — the well table above frequently disagrees with the system average. Full method on the science page, and every input is traceable through the research index.