Upper Nene Valley Gravel Pits. 07/04/11; England; 1,358 ha; 52°20'04'N 000°34'56'W. Site of Special Scientific Interest (SSSI), Natura 2000 (SPA). A chain of both active and disused sand and gravel pits including open water, reed swamps, marshes, pastures and grasslands. The range of habitats and the varied topography of the lagoons regularly provide valuable resting and feeding conditions for more than 20,000 wintering waterbirds, especially ducks and waders. The site is important for flood control, and human activities include recreation (bird-watching, walking, fishing, sailing, canoeing, waterskiing, cycling), research and environmental education. Potential threats to the site include urban development, vegetation succession, and invasive plants such as Nuttall's Pondweed Elodea nuttallii. There is a visitor centre at Stanwick Lakes. Ramsar Site no. 2023. Most recent RIS information: 2011.