Eutrophication modelling of reservoirs in Taiwan

Two reservoirs in Taiwan were modeled to simulate the hydrodynamics and water quality in the water column. The modelling effort was supported with data collected in the field for a 2-year period for both reservoirs. Spatial and temporal distributions of temperature in the water column of the two reservoirs were well reproduced by the hydrodynamic model. Model calculated concentrations of key water quality constituents such as nutrients, dissolved oxygen, and algal biomass matched the measured values closely in both reservoirs. Most importantly, vertical stratification of temperature and dissolved oxygen in the Tseng-Wen Reservoir was mimicked by the model throughout this 2-year period. The calibrated model was then used to simulate water quality response to various nutrient reduction scenarios. Model results reveal that a 30e55% reduction of the phosphorus loads will upgrade the existing eutrophic/mesotrophic to oligotrophic conditions in the Te-Chi Reservoir.