Lake Wesseker has been a nature reserve since 1961 and is part of the European network of protected areas "NATURA 2000". The artificial drainage of the Oldenburg Graben has significantly changed the original character of the lake. Since the 1930s, technical optimization of the drainage systems and intensification of land use in the surrounding area have allowed Lake Wesseker to shrink to a third of its former size of around 150 hectares. Despite the designation as a protected area, there is a further impoverishment of the communities. Encroaching reeds and deposited layers of mud make the lake disappear. The mean water level is only 0.2 meters.