A number of the individual reserves in the World Network (currently, 408 sites in 94 countries) have a primary focus on a particular river or lake system. Examples include: Neusiedler See (Austria), Mare aux hippopotames (Burkina Faso), Tonle Sap (Cambodia), Redberry Lake and Lac St Pierre (Canada), Trebon (Czech Republic), Flusslandschaft Elbe (Germany), Lake Fertö (Hungary) Lake Oromeech (Iran), Lukajno Lake (Poland), Danube Delta (Romania/Ukraine), Astrakhanskiy, Baikalsky and Barguzinskyi (Russian Federation), Delta du Saloum (Senegal), Lake Torne Area (Sweden), Isle Royale and Land Between The Lakes (United States), Tara River Basin (Yugoslavia).
In addition, different dimensions of ‘water and ecosystems’ are being addressed in many individual biosphere reserves: conflicting water usages and new water resource challenges, particularly in coastal and island situations (Boloma Bijagós, Can Gio, Ichkeul, Lanzarote, Palawan, Ranong); water resources management at the regional scale (e.g. Everglades, Flusslandschaft Elbe); role of forested watersheds as a source of water supplies for large urban conglomerations (e.g. Mata Atlântica, Cerrado) and contiguous agricultural areas (Mount Kenya); links between water resources management and biodiversity conservation (e.g. Luquillo); maintaining water quality, combating ecosystem degradation and rehabilitating impoverished ecological systems (e.g. Fitzgerald, Oasis du sud marocain, Omayed).