Author(s): S. J. Wright; A. A. Honarpisheh
Linked Author(s):
Keywords: Gas transfer; Thermal modeling; Supersaturation; Dissolved gas; River modeling
Abstract: Releases of water from hydroelectric storage reservoirs on the Snake River system are being managed to provide for higher summertime flows in order to help restore an anadromous fishery. This flow augmentation has an additional benefit of lowering water temperatures below lethal levels in late summer but at the expense of increased levels of dissolved gas super-saturation which can also prove lethal. In order to assess the potential impacts of different proposed schemes for managing reservoir releases, a numerical model was developed to simulate the thermal and dissolved gas transport downstream from the storage reservoir. An available model, MIKE-11 was utilized in the modeling effort and data collected by a variety of public agencies was assembled to guide the model formulation and calibration. A careful analysis of the data revealed that some of the data was of poor quality and it was necessary to screen the data to obtain a valid data set for model calibration and verification. The calibrated model is shown to be capable of reproducing both temperature and dissolved gas conditions within the Clearwater River over a variety of summertime flow conditions. The calibrated model is applied to analyze the relative merits of two proposed schemes for managing the releases from the Dworshak Reservoir.
Year: 2003