The solution to lack of burial sites is not to remove open land from public use in densely populated areas, it is to do exactly what the Victorians did when the opened Camberwell, Nunhead, and other cemeteries in what are now London suburbs. They should be outside urban/suburban areas, close to the M25 and to rail connections from population centres in Southwark. This is exactly what other councils (Westminster) already do and has a long tradition in Britain.