A Marine Anoxic Event on the Brittany Coast, July 1982

The release by the Arzal Dam in W France of a large amount of fresh water into the Bay of Vilaine during four days of July 1982 led to bottom water oxygen depletion and demersal fish mortality, by stratifying the water column and preventing the ventilation of the bottom waters. Other cases of seasonal anoxia or hypoxia in coastal bottom waters under the influence of a buoyant river plume are reviewed.