| A two dimensional laterally averaged hydrodynamic and water quality model was developed using CE-QUAL-W2 for Lake Eucha, Oklahoma. The model was calibrated with vertical profiles (temperature, dissolved oxygen, phosphate, nitrate plus nitrite, and chlorophyll a) collected at 4 locations in the reservoir by the City of Tulsa from 2002 through 2004. This model was developed as a means of predicting the response of the phytoplankton community in Lake Eucha resulting from decreased nutrient (nitrogen and phosphorus) inflows. Inflowing nitrate+nitrite and phosphate concentrations were reduced by 10, 25, 50, 75, and 90% simultaneously and the response of chlorophyll a was simulated. Decreasing the inflow of phosphate had a more significant effect on the mean and maximal chlorophyll a concentrations in the epilimnion than did decreases in nitrate+nitrite. However maximal external nutrient reductions were not sufficient to change the reservoir from eutrophic to mesotrophic during the modeled period. |
