The Walthamstow Reservoirs in the Lea Valley demonstrate the visual potential of bunded reservoirs, and should become the most beautiful water park in London [Fig 5.14]. Only registered fishermen and ornithologists are admitted. Children under 8 are excluded and children between 8 and 16 must be accompanied by an adult. The stylised shapes of the water bodies resemble the great eighteenth century garden at Studley Royal in Yorkshire. Walthamstow is also a designated Site of Special Scientific Interest and has a large heron population. One of the main reasons for the beauty of the Walthamstow Reservoirs is the fact that the spaces between the reservoirs are filled with soil and planted with trees. This has created an oasis of water and trees which is raised above the urban area and yields fine views over the city. Since the soil between the reservoirs is not structural, the trees do not constitute an engineering hazard. In this respect they correspond to the trees which have been planted on the toe weight and mount at Brenig.