Case Study: Sediment Control at Water Intake for Large Thermal-Power Station on a Small River

A large thermal-power station drawing water from a small alluvial river had a chronic problem with alluvial-bed sediment buildup at the station’s river-water intake structure. The problem required expensive corrective dredging and adversely affected the station’s fuel-consumption efficiency. This case-study paper describes how the sediment problem was successfully controlled by means of modifications to the area in front of the intake and the upstream riverbank. The modifications comprised erosion-promoting vanes and a skimming wall, together with realignment of the riverbank upstream of the intake. A hydraulic model was used to aid the design of the modifications. Installation of the modifications required construction techniques that enabled the intake and power station to continue operating while the modifications were being installed.