3D salinity intrusion modeling for estuaries and rivers — protecting water supplies, oyster beds, and seagrass from saltwater intrusion.
Saltwater intrusion — driven by reduced freshwater flows, sea-level rise, and urban development — threatens freshwater ecosystems, water supplies, and sensitive habitats like oyster beds and seagrass. Three-dimensional salinity modeling is essential for assessing these risks and evaluating management options.
EFDC+‘s Sigma-Zed vertical layering accurately simulates how fresh and salt water interact and stratify in estuaries and river systems — outperforming comparable tools. EEMS includes full post-processing support to analyze salinity patterns, track seasonal and multi-year trends, and compare management scenarios.
The Chesapeake Bay has been used to benchmark EFDC+‘s parallel processing capabilities, with a 1-million-cell model testing scalability across many processors. The application shows that EEMS can handle large, complex estuaries where accurate salinity stratification is essential for water quality and habitat management.
EEMS has been applied to the Delaware River for salinity modeling and contaminant studies, including work supporting PFOA assessment for the New Jersey Department of Environmental Protection. The 3D model captures the salt front dynamics that affect both water supply and aquatic habitat in this major East Coast estuary.
EFDC+ with Sigma-Zed was used to assess how deepening Jacksonville Harbor would change salinity conditions in the Lower St. Johns River. The model accurately reproduced the estuary’s stratified conditions and was used to evaluate risks to oyster beds, seagrass, and other salinity-sensitive habitats. Read the external publication →
An EFDC+ model was built for the Ocean Pointe area of Hawaii to assess how major freshwater storm drains affect near-shore salinity. Results were evaluated against the 31.5 ppt salinity standard needed to protect nearby coral reefs — a direct connection between hydrodynamic modeling and reef conservation.
When Lake Okeechobee releases large volumes of fresh water into the St. Lucie Estuary, salinity drops enough to damage oyster beds and seagrass. EEMS was used to develop a 3D model that evaluates these freshwater inflow impacts, giving decision-makers a clearer picture of the trade-offs involved in Lake Okeechobee management.
