This former drinking water reservoir was in operation until 1979. Now managed by Northamptonshire County Council, it is a Site of Special Scientific Interest. The waters are nationally renowned for tench fishing; alternatively, enjoy meadowland and lakeside walks - there's even a Water Works Heritage Trail to follow. There is also a small arboretum of exotic trees, a butterfly garden, an amphibian pond (pond dipping permitted!) and children's play area. Sets of boules are available for hire from the ranger's office. Two bird hides provide opportunities for birdwatchers to observe terns, swallows and various duck and goose species.