In the Texas Gulf Coast region, abundant groundwater use can cause aquifer compaction, leading to land surface subsidence. With projected population growth and increased water demand, evaluating future subsidence impacts is crucial for water resource planning. This study models flood risk and estimates economic impacts of future subsidence in the Spring Creek Watershed, located in four counties across southeast Texas. Subsidence projections were used to create a new pluvial 2D HEC-RAS model that quantifies the flood risk of future subsidence projected to 2070 for the entire watershed. This effort involved calibrating a baseline scenario, modeling two subsidence scenarios using two storm events to calculate flooding impacts, and evaluating economic losses of such impacts using the Go-Consequence Hazard tool. The study revealed that subsidence causes heterogeneous and greater flood risk impacts in areas with higher projected population growth, with economic impacts valued from multi-millions to half a billion dollars.
Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025