Using numerical models and acoustic methods to predict reservoir sedimentation

Abstract

This study draws on drainage basin hydrography, numerical modeling and geographic information system (GIS) techniques in concert with dual frequency echo sounder data to estimate sediment thickness when initial surveys are unavailable or inaccurate. Tahtali Reservoir (Turkey), which provides 40% of water supply to the city of Izmir, was selected as the study site. Deposition patterns within the whole lake were estimated with a 3-D hydrodynamic and sediment transport model applied to Tahtali Reservoir. The numerical model simulated lake response to wind forcing and inflows and/or outflows and was used to describe sediment deposition patterns resulting from the erosion of soils quantified by the implementation of Universal Soil Loss Equation (USLE) to the whole watershed. Surveying of the lake via dual frequency (28/200 kHz) echo sounder system revealed the current bathymetry, and sediment thickness was estimated from the difference of depths measured by the dual frequency sounder along surveyed transects. These results were compared to the modeled sedimentation thicknesses and to preliminary estimates of watershed sediment yield estimated by USLE. Results of this study can be used for further water quality studies and for long term management plans.TÜBİTAK project No: 104Y323 and European Commission project No: 28292 (RESTRAT

Predicting the Water Level Fluctuation in an Alpine Lake Using Physically Based, Artificial Neural Network, and Time Series Forecasting Models

“…In this study, we adopted the well-known three-dimensional hydrodynamic model EFDC (Environmental Fluid Dynamics Code) [27,28] which has been widely used for describing flow and transport processes in surface water systems, for example, rivers, lakes, estuaries, reservoirs, wetlands, and coastal regions [29][30][31][32][33]. This model solves the 3D equations of motion and continuity equation with the Mellor-Yamada level 2.5 turbulence closure scheme [34][35][36] under the stretched (or sigma) vertical coordinates and Cartesian (or curvilinear) orthogonal horizontal coordinates.…”

Modeling water ages and thermal structure of Lake Mead under changing water levels

“…The details of the EFDC model are documented by Hamrick (1992). The model has been extensively applied to simulate circulation, thermal stratification, sediment transport, water quality and eutrophication processes in numerous lakes, rivers and estuaries (e.g., Ji et al 2007, Elci et al 2009). …”

Estimating the Wind-Generated Wave Erosivity Potential: The Case of the Itumbiara Dam Reservoir

“…This problem causes a reduction of the effective reservoir storage capacity, decreases the effective lifespan of dams and lessens various reservoir functionalities [8]. Many researchers studied the effects of erosion by rainfall [15][16][17][18][19] and waves [2,[20][21][22] to predict or examine sediment yield in reservoir.…”