South Thames Estuary and Marshes South Thames Estuary and Marshes South Thames Estuary and Marshes is a biological Site of Special Scientific Interest which stretches between Gravesend and the mouth of the River Medway in Kent. Part of it is a Nature Conservation Review site, Grade I, and part is a Royal Society for the Protection of Birds nature reserve. It is part of the Thames Estuary and Marshes Ramsar internationally important wetland site and Special Protection Area under the European Union Directive on the Conservation of Wild Birds. Over 20,000 waterfowl use this site, and some species are present in internationally important numbers. There
Wouri estuary Wouri estuary The Wouri estuary, or Cameroon estuary is a large tidal estuary in Cameroon where several rivers come together, emptying into the Bight of Biafra. Douala, the largest city in Cameroon, is at the mouth of the Wouri River where it enters the estuary. The estuary contains extensive mangrove forests, which are being damaged by pollution and population pressures. The estuary lies to the east of Mount Cameroon and empties into the Bight of Biafra. It is fed by the Mungo, Wouri and Dibamba rivers. The estuary lies in the Douala Basin, a low-lying depression about on average about