Considerations for Flow Alternatives that Sustain Savannah River Fish Populations

Proceedings of the 2003 Georgia Water Resources Conference, held April 23-24, 2003, at the University of Georgia.Flows in the lower Savannah River have been considerably altered since the construction of Strom Thurmond Dam in 1954. The effects of this flow alteration on fish have received little attention until recent years. We are collaborating with The Nature Conservancy and the Army Corps of Engineers to develop flow alternatives below Strom Thurmond Dam by evaluating relations between flow regimes and specific life history stages of riverine and diadromous fishes within shoal, floodplain, and estuary habitats. Although restoring a natural flow regime to the Savannah River may not be a feasible objective, alternatives to current flow management could enhance the ability of the river to support native fish populations. Evaluations of flow alternatives should consider effects on habitat stability in the shoals, interannual and intra-annual flow variation, and provision for fish access on and off of floodplain habitats. Evaluating effects of flow alterations on estuarine habitats is complicated by the often larger effects of physical channel alteration, especially harbor deepening