River Pool, by DICKSDAILY
London's smaller rivers are an endlessly fascinating yet little-appreciated feature of the London topography. Boris wants to bring them back. Londonist wants to track them. Thames21 wants to clean them up...and they need your help.
From 30 May to 7 June, Thames21, in conjunction with a whole heap of partner organisations, are looking for volunteers to beautify three of South London's water courses. The Ravensbourne, Quaggy and Pool are all choked with Himalayan Balsam, an invasive species that's playing havoc with local ecosystems. The week of volunteering will help cut back this troublesome alien, as well as clearing up litter along the rivers. Various stretches need your help, including a hidden section of the Quaggy, not normally accessible to the public. We're signed up for the Wednesday slot, so if you want to join us, register here.