Advanced Water Management Through Hydrodynamic Modelling: A Study For The Aid Of The Water Resources In China

Abstract

To forecast the medium-term development of the Nam Theun 2 Reservoir's water quality and to measure the impact of different scenarios, a 3D water quality model was used. Although the hypolimnion will be anoxic in some places of the Reservoir, 15-year models indicate that the oxygen content in the water column will continue to grow. Also, as time goes on, less and fewer reduced chemicals will be present. Using two situations in which either natural or human-induced forcings have been altered, the importance of hydrodynamics in the development of water quality is highlighted. When looking at models from different years with different hydrometeorological circumstances, it becomes clear that the length of major hydrometeorological events, such as rainfall, floods, and drops in air temperature, significantly affects the seasonal changes in water quality over the whole reservoir. Commissioning the power plant right after impoundment would have altered the physicochemical quality of the water discharged downstream, according to simulations. Lastly, the model has been used to measure the effects of a rise in the incoming flux of NO3- and PO4-3 after possible changes to the land use within the watershed. Both individually and in combination, the fluxes have been doubled.