Study of a Fish-Friendly Pump System As a Mean to Improve Fish Survival: A Case Study at Cordemais' Power Plant (Loire River, France)

Cordemais’ production unit is a coal-fired power plant located on the Loire River estuary (oil is also used for a few hours a year). Two units producing each 600 MW require the use of 46 m³/s of cooling water, pumped in the Loire River. This water goes through a drum screen (5 mm mesh size, filtering organisms and debris), cools the condenser and finally is released in the Loire River. Until now, debris and organisms were pumped in the drum screen room by three pumps and discharged in the Loire River by pipes leading to high organisms’ mortality. Since 2007, French law has imposed Cordemais’ plant to provide an action plan to reduce drum screen impingement mortality. Indeed, an impingement study conducted in 2011 has highlighted the quantity and diversity of organisms impinged at the plant.The Scoop-a-Fish project is a test of a fish-friendly pump in collaboration with Electric Power Research Institute and Alden Research who designed a collection box allowing organisms sampling from pump discharge with no additional damage. Samples have been conducted in 2013 and 2014 and individuals sampled were hold during 24 hours. Results of this survival study are exposed and their variability is discussed.