Challenge
Challenge
A 3,500 km² coastal delta faced overdraft and the risk of seawater intrusion. Managers needed to know which pumping regimes the aquifer system could sustain.
Approach
Approach
We built a quasi-three-dimensional transient MODFLOW model of the multi-layered aquifer system, calibrated on pumping tests and 24 monitoring wells (13 shallow, 11 deep), then coupled it with GIS-based genetic algorithm optimization to evaluate management scenarios.
Deliverables
What the client received
- Calibrated basin-scale groundwater flow model
- 12 management scenarios with sustainable pumping envelopes
- Peer-reviewed methodology (Hydrogeology Journal, 2017)
Outcome
Outcome
Nash-Sutcliffe efficiency held above 0.78 across a 15-year record (calibration 1997-2006, validation 2007-2011). Published as Sahoo & Jha (2017), Hydrogeology Journal, doi: 10.1007/s10040-017-1610-4.
- NSE > 0.78
- Model performance
- 3,500 km²
- Delta modeled
- 15 yr
- Simulation record