Sediment Flushing from Reservoir and Ecological Impacts

6 pages•Published: September 20, 2018

Abstract

Dams cause a sediment transport trapping phenomenon and the effects can be the reduction of reservoirs operations, the decreasing of the storage, a channel erosion of the downstream watercourse and habitats pauperization. A possible method used to preserve the reservoir volume and the sediment continuity downstream the dam is to operate sediment flushing. In this work, the sediment flushing phenomena and its impact on morphology and ecology is investigated. In particular two possible flushing strategies are proposed. The two strategies differ for the flow rate, sediment concentration and event duration. The results are obtained using an original CFD model developed at the University of Trento. The CFD model has the possibility to simulate the erosion and deposition phenomena and to calculate the severity of the ill effects (SEV parameter) for juvenile and adult Salmonids. The results showed that the two strategies have very different effects on morphology and habitat. The strategy that involve lower flow rate and concentration with higher event duration, seems to minimize the deposition phenomena and the effects on the habitat.

Keyphrases: Ecological Impacts, flushing, Reservoirs, Severity of ill effects

In: Goffredo La Loggia, Gabriele Freni, Valeria Puleo and Mauro De Marchis (editors). HIC 2018. 13th International Conference on Hydroinformatics, vol 3, pages 1692--1697

Links:	https://easychair.org/publications/paper/D9Fm
	https://doi.org/10.29007/1fsv