Catchment projects

Hover over a numbered spot to see a project summary. Click on a spot to see the full project details. Alternatively view the project list.

The Pinn flows for 12 miles from north east of Harrow Weald Common to join the Frays River at Cowley. The Ash leaves the Colne at Staines and flows east for 6 miles to the Thames. The Duke of Northumberland and the Longford Rivers flow from the Colne near Heathrow to the Crane.

The Colne Valley Park covers 43 square miles of countryside on the edge of London, Herts, Bucks, Berks and Surrey. The Park includes over 70 lakes, 13 Sites of Special Scientific Interest, 5 country parks and hundreds of other green spaces.

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Last updated: 7 November 2023

Design by LTD Design Consultants and build by Garganey Consulting. From an original concept by the Herts and Middlesex Wildlife Trust.