Thermal Compliance

The Black Warrior is one of the most intensively managed river systems in the southeastern United States, where a cascade of locks and dams balances hydroelectric generation, municipal water supply, and commercial navigation. DSI developed an EFDC+ hydro-thermal model of the river to simulate coupled hydrodynamic and temperature dynamics across the regulated reaches, giving Alabama Power a defensible scientific basis for assessing environmental impacts, demonstrating regulatory compliance, and optimizing day-to-day operations.

For the regulated reach between Logan Martin and Lay Dams, DSI built a real-time, three-dimensional EFDC+ model that helps Alabama Power maintain compliance with state thermal standards. The system continuously ingests live data on dam releases, power plant discharges, tributary inflows, and meteorological conditions, and was rigorously calibrated against measured temperatures and water levels. Running 24/7 as an operational decision-support tool, it allows operators to anticipate thermal exceedances before they occur rather than react after the fact.

The Southwest Florida Water Management District used EFDC+ to develop a fully 3D model of the Chassahowitzka spring-fed river and estuarine system, quantifying how reduced spring discharge alters temperature and salinity throughout the network. The model pinpointed which refuges still meet manatee thermal habitat criteria under critical low-flow conditions — directly informing the minimum-flow rule needed to protect this federally listed species while balancing regional groundwater demands.

Lake Washington’s steep bathymetry and decades of high-quality temperature observations make it a benchmark site for EFDC+‘s Sigma-Zed vertical layering. DSI constructed a 1,183-cell, 55-layer model that accurately reproduces the formation, persistence, and turnover of the lake’s thermal layers throughout the annual cycle. The model runs in real time and feeds a publicly accessible web portal — demonstrating both EFDC+‘s computational performance and its value as a transparent scientific communication tool. Additional resources: free grid and video walkthrough.

EEMS has been applied to the Delaware River for thermal and water quality assessment work, leveraging the model’s heat transport capabilities to evaluate temperature regimes, quantify impacts on aquatic ecosystems, and support compliance with state and federal water quality standards across one of the most industrially significant watersheds in the eastern United States.

DSI applied EFDC+‘s Sigma-Zed layering to Lake Mead, the Colorado River reservoir impounded by Hoover Dam, to test the model’s ability to resolve thermal structure in a large, deep, strongly stratified system. Results showed that EEMS accurately reproduces both the seasonal formation and the spatial evolution of temperature layers — a capability directly relevant to water supply forecasting, recreational management, and ecological assessment in the increasingly stressed Colorado River Basin.