ABSTRACT
Besides storing water, dams are also erected to create a hydraulic head or a water surface. A hydraulic head increases the net pressure on hydropower turbines and may improve river navigation by creating sufficient backwater. Dams and hydropower are strongly related. Hydropower is still the cheapest and most flexible renewable energy with a significant potential worldwide. While ancient dams and reservoirs mainly served for drinking and irrigation water supply as well as flood protection purposes, many larger dams were built from the 16th century to drive water mills and later hydropower plants. Dam and reservoirs are among critical water infrastructures whose failure may have catastrophic consequences with risk of fatalities and high economic losses. The construction of a dam across a valley with its river, including a river diversion, is a major engineering challenge involving considerable risk. The notion river diversion comprises all structural measures for controlling a river during construction.
