Neva Bay
Construction of the Saint Petersburg Dam reduced water exchange of the Neva Bay with the eastern part of the gulf by 10–20% that increased the contamination level of Neva Bay. The largest changes occur within from the dam. Some shallow areas between Saint Petersburg and the dam are turning into swamps. Waterlogging and the associated rotting of plants may eventually lead to eutrophication of the area. Also worrying is expansion of oil ports in the gulf and the construction of a treatment center for spent fuel from the Leningrad Nuclear Power Plant.