Model studies concerning design modifications to improve spillway performance–Teesta-IV Dam spillway, Sikkim

The most significant development activity on the Teesta River in India is the construction of a series of cascade dams for hydropower generation in the state of Sikkim, India. Approximately 30 major hydropower projects have been planned on the Teesta River, with a planned capacity of over 5000 MW of electricity. This paper discusses hydraulic model studies conducted at Central Water and Power Research Station, Pune, India, for Teesta-IV Project in Sikkim which played an important role in enhancing the overall performance of spillway and energy dissipator by incorporating various modifications such as providing curved dam axis, tilting the dam axis anti-clockwise by about 3°, modification of breast wall profile, etc. The details of model studies conducted for improving the overall performance of spillway and energy dissipator are described in the paper. © 2018, © 2018 Indian Society for Hydraulics.