Using Environmental Fluid Dynamics Code Plus (EFDC+), DSI developed a two-dimensional (2D) and three-dimensional (3D) model of the Little Bow River, which extended about 165 km and included an in-stream reservoir (Twin Valley), and a 55 km tributary (Mosquito Creek). The reaches were represented by 2D grids and the reservoir was represented using 3D grids. The model boundary condition inputs were provided using monitoring data and a watershed model developed using Soil and Water Assessment Tool (SWAT).
The model simulated hydrodynamics, temperature, ice, dissolved oxygen, nutrients, macrophytes, algae, and the processes involved in the complete nutrient cycle. Following the calibration of the model for all physical, chemical, and biological parameters, DSI used the calibrated model of the complete system to evaluate multiple management scenarios, including flow diversion at Highwood, reservoir operations, and Waste Water Treatment Plant (WWTP) effluent water quality control.
DSI submitted the complete model and the final report to AEP and provided training to agency staff. AEP uses the model for management scenario evaluation.