Definition, London’s Resource

Lakes, ponds and reservoirs include all areas of standing open water. Reservoirs, by definition, are artificially created water-bodies, some of which enclose a very large area of water. All of London’s lakes are also likely to be artifacts resulting from the damming of streams to create water features in parks and other formal landscapes, or as a consequence of mineral extraction (sand and gravel pits). Some of London’s ponds may have natural origins but most extant ‘natural’ ponds are likely to be former farm ponds or marl and clay pits. In more recent years many new ponds have been dug for aesthetic or nature conservation ponds in parks, gardens and amenity open spaces; many of these newer ponds have artificial liners as they do not naturally hold water.

The total area of open water documented in the London Wildlife Habitat Survey 1984/85 is provided in Table 1. This figure is based mainly on the larger water-bodies (lakes and reservoirs) and excludes the majority of smaller ponds. Boroughs such as Enfield, Waltham Forest and Hillingdon have a particularly high proportion of standing open water because of the presence of large reservoirs (in Waltham Forest and Enfield) or extensive former gravel workings (in Hillingdon). The map provides a picture of the resource across the capital.