Lower Mississippi Delta · AR, MS, LA, MO, TN

Mississippi Embayment Aquifer

Is the Mississippi Embayment aquifer being over-pumped?

Mississippi Embayment Aquifer serves about 3 million people and underpins roughly $12B of agriculture across AR, MS, LA, MO, TN. This model puts its probability of reaching crisis conditions at 0.226% by 2100 (95% CI 0.188%–0.272%), making it stable at the aquifer-average level, which hides sub-regional stress. Expected crisis year is approximately 2074. Measured water levels are falling about 0.99 ft/yr.

Key figures

Crisis probability by 20400.0%
Crisis probability by 20600.048%
Crisis probability by 21000.226% (95% CI 0.188%–0.272%)
Expected crisis year2074
Observed decline rate0.9890 ft/yr
Latest observed level29.31 (2025)
Year-to-year volatility7.642
Drought persistence φ (AR(1))0.6983
Population served3M
Agricultural value$12B
Modelled annual damage at crisis$5.1B

Monitoring wells in this system

Aquifer averages hide local stress. These are the Mississippi Embayment wells that appear in the 20 most at-risk sites nationally.

WellStateDecline (ft/yr)P(crisis) 2060Expected crisis
19S12W13AAA1AR0.97100.0%2026

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.