Fusegate operation at Kastraki dam, Greece: Storage and efficiency gains

Kastraki dam is part of the Acheloos hydropower cascade in western Greece. Commissioned in 1969, the project contributes significantly to renewable electricity production, with an installed capacity of 320 MW and a typical pre-modification annual energy production of 640 GWh. The originally designed effective live storage was about 53 x 106m3 with a total capacity of about 785 x 106m3. The side spillway was an uncontrolled ogee structure with a crest length of 120 m and an outflow capacity of 3500 m3/s. The project owners wanted to increase storage and operational flexibility without modifying the dam crest or relying on mechanical gate systems, while also maintaining discharge performance and dam safety. The installation of Fusegates was selected for this purpose. This paper documents the rationale, design basis, and quantified recommendations, from 15 years of their operation.