Boundaries for London boroughs have recently been imported from OS Opendata Boundaryline. On balance I think this is a good thing because the boundaries are much more detailed than the straight lines that much of London had, being separate ways they are more robust than doubling up roads as boundaries and London has got a good enough community to take them on; that last is where I come in.
I have surveyed the boundary between the London boroughs of Richmond upon Thames and Wandsworth. Much of the boundary follows the Beverley Brook;this stream is roughly mapped at the moment. There are two places where the boundary goes in another direction. There is a chunk of Barnes Common that is west of the stream but in Richmond. The crossing of Lower Richmond Road is clearly visible in terms of signs and Wandsworth street name signs on the west sides of Hallam Road and Beauchamp Terrace confirm that the boundary is west of the roads. The other exception is Richmond Park, where the whole park was incorporated in Richmond in 1994.making mapping the boundary easy.