Thames21 is a charity working in partnership with local communities along the Thames River estuary and catchment, and in London city centre, to restore and clean 400 miles of
waterways along the Thames.

In numbers: approx. 7,000 volunteers engaged annually, 35 local River Action Groups, 11
trustees, 59 funders Thames21 empowers local community groups to become self-sufficient in tackling local environmental issues relating to their local rivers.

Through its network of River Action Groups, Thames21 embeds itself in local communities by supporting them with start-up assistance and ongoing support, beginning with a training programme to upskill local leaders into setting up their own river restoration network.
Thames21 also runs various funded projects, such as river stewardship initiatives in partnership with corporations, and environmental monitoring involving citizen scientists. Most recently Thames21 has partnered with Middlesex University, the Zoological Society of London, and the South East Rivers Trust in a road run-off monitoring project funded Greater London Authority, Transport for London, and the Environment Agency.