London has two large concentrations of water supply reservoirs, in the Lea and Colne Valley regional parks. Most of the reservoirs are retained by bunds of earth and enclosed by high security fences so that they are visually and physically severed from their environment. In many cases the bunds resemble railway embankments. Queen Mother Reservoir, near Datchet, is the most recent bunded reservoir. It has public access for sailing, fishing, putting, and horse riding. A clubhouse and restaurant on top of the embankment command a delightful view of the water and Windsor Castle. The recreation facilities were designed by the Thames Water Authority's architecture and gardening staff. No specialist landscape advice was obtained and, because the reservoir was constructed under powers given by Act of Parliament, there was no need for planning permission (Thames Water Authority 1978). It is not an unsightly place but many opportunities have been missed. Most of the other 34 bunded reservoirs in the London area have been less well designed and have less recreational use. Some are completely closed to the public and others are open only to sailors, fishermen, ornithologists or, in some cases, all three groups. Control points are manned when the reservoirs are open.