Session K.pdf - Clarkson University

Fig. 1. Suldalslagen from Lake Suldalsvatn to the sea (Sandsfjorden). Kvilldal and Hylen are hydro powerplants and the heavy arrows indicate the flow directionMODELSWe used the two-dimensional lake model QUAL2E(www.epa.gov/docs/QUAL2E_WINDOWS/index.html ) to model the water temperaturesin Lake Suldalsvatn.CalculateWater temperatureand dischargeWeather dataQUAL2EQUAL2ELake Suldalsvatnmain basinTarmenRICESuldalslågenSandsfjordenFig. 2. A sketch of the simulations from Lake Suldalsvatn to the seaThe lake is naturally divided at a shallow and narrow threshold called Suldalsporten.The upper basin is more than 300 m deep while the lower part is less than 40 m deep.To be able to use a rough grid net we divided the simulation into two simulations wherethe Suldalsporten was regarded as a river between two lakes. The river from Suldalsosento the sea (Tjelmane) was analysed by the one-dimensional model RICE (Lal &Shen, 1989). Fig. 2 gives an overview of the simulations.Each of the lake models used two elements in the length direction and had a verticalresolution close to 3 m. The river was modelled as a channel with constant shape and360