Prediction of Temperature Due to Heated Discharges

A phenomenological model has been developed for the prediction of subsurface temperature from a given set of surface isotherms due to heated effluent discharge from a thermal-electric power plant. When surface isotherms are obtained from infrared overflight measurements the model can provide estimates of subsurface isotherms. For given categories of surface discharge and lake conditions, exponential equations relating areas and temperatures along the center line of the plume for surface isotherms to areas and center line temperatures for subsurface isotherms are used to predict subsurface temperatures within approx 0.25°C (0.45°F) of the measured temperatures, for depths up to 10 ft below the surface. The data used to calibrate and verify the model are a comprehensive set of triaxial hydrothermal surveys of Lake Michigan, conducted by Argonne National Laboratories. The model is also used to predict subsurface temperatures in Lake Ontario.