THXP Intake Analysis (Laos)

DSI conducted a numerical hydrodynamic modeling study for the support of intake design modifications for the existing dam and intake works on the Nam Theun River, Bolikhamxai Province, Lao PDR. This project is part of the Theun-Hinboun Expansion Project (THXP) under the Theun-Hinboun Power Company, Ltd. (THPC). The existing dam impounds a run of river reservoir that is called the Headpond. The EFDC hydrodynamic model was calibrated to a physical model of the original design. The numerical model results were within 2% of the physical model for depth average velocities. The THXP design process considered several layouts for the expansion intakes on the Headpond. All of the design alternatives left the current intake as is and will retrofit the existing THPC weir with the intake needed for the expansion. One or more of the existing gates would be modified to accommodate the new intake. Various design alternatives were evaluated and recommendations made with respect to the best alternative. The following figure provides a comparison of two alternatives.