River Colne Catchment Action Network

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 River Misbourne is a chalk stream which flows for 17 miles through the Missendens, Amersham, the Chalfonts and Denham. The Alderbourne runs from near Fulmer and flows for 6.5 miles. Both rivers flow through the Colne Valley Park to join the Colne at Denham and Uxbridge Moor respectively.

The Colne Valley Park is a mosaic of farmland, woodland, water and villages containing 125 miles of watercourse, 167 miles of paths and hundreds of green spaces.

27. Lower Misbourne habitat enhancements

Aims: Improve wildlife corridors; Manage flow; Work together

River enhancements to improve habitat from upstream of the Colne Valley Park Visitor Centre to the confluence with the Colne.

22. Higher Denham habitat enhancement

Aims: Involve people with their local waterbodies; Improve wildlife corridors; Work together

Local volunteers completed the enhancement of the lower Misbourne near Higher Denham in May 2014, improving habitat for fish and wildlife.

24. Misbourne Water vole monitoring scheme

Aims: Control invasive non-native species; Involve people with their local waterbodies; Improve wildlife corridors

Following on from the discovery of water voles along the lower Misbourne a monitoring scheme was set up by BBOWT in 2009.

23. Riverfly monitoring

Aims: Involve people with their local waterbodies; Improve water quality

Volunteers from the Chiltern Society and Misbourne River Action monitor riverflies at 12 sites along the Misbourne. Monitoring began in 2011 and results are posted here.

21. Gerrard's Cross Golf Club - Channel restoration

Aims: Involve people with their local waterbodies; Improve wildlife corridors; Work together

Project to remove weirs and concrete lining of river channel, enhance habitat and improve access for golf club users.

20. River dipping

Aim: Involve people with their local waterbodies

Creation of an access beach to enable school groups and visitors to continue to river dip whilst minimising erosion to the river bank elsewhere.

28. Denham Country Park Backwater

Aims: Improve wildlife corridors; Work together

Working in partnership to create a backwater on the River Colne in Denham Country Park.

16. Reedbed restoration at Maple Lodge Nature Reserve

Aim: Improve wildlife corridors

28. Giant Hogweed Control

Aim: Control invasive non-native species

Giant Hogweed found at the confluence of the Pinn and Frays

26. River Restoration at Denham

Aim: Improve wildlife corridors

River and ditch restoration in pursuit of Water Framework Directive improvement

Remove trees, other woody scrub and bramble from sections of the Fray’s River and ditches on Fray’s Farm Meadows London Wildlife Trust (LWT Reserve). Work on the Fray’s River was carried out in February 2016 to remove overhanging branches but retaining woody habitat already in the river. The extra light allowed on to the river should encourage the growth of marginal plants that provide ideal water vole habitat while the woody material in the river will act as nursery areas for small fish. The photographs show the situation on the river immediately before and after the work.

25. Colne Valley Water Vole Conservation

Aim: Improve wildlife corridors

Maintain and extend the surveying of water bodies to look for evidence of water voles and hence increase knowledge of the presence and absence of water voles in the valley. Increase the number of rafts to monitor and control American mink, the prime predator of water voles. Wherever possible improve habitats to benefit water voles and other riparian wildlife.

15. Lower Colne Mink control

Aims: Control invasive non-native species; Improve wildlife corridors

American Mink monitoring and control for the benefit of Water Voles and other native wildlife.

3. Stockers Weir

Aims: Improve wildlife corridors; Manage flow

Weir modifications and bypass channel to create fish passage and improve flow upstream of the weir.

14. Uxbridge Alderglade

Aim: Improve wildlife corridors

Habitat enhancements and access improvements at Uxbridge Alderglade Nature Reserve.

13. Black Park Alder Carr

Aim: Improve wildlife corridors

Habitat enhancements in the Alder Carr to slow drying out of the wet woodland Site of Special Scientific Interest.

12. Colne Valley Park short walks

Aim: Involve people with their local waterbodies

Update and reprint the series of 20 short walks throughout the Colne Valley Park

11. Floating Pennywort removal, Denham

Aim: Control invasive non-native species

Programme to remove Floating Pennywort from the Colne at Denham

6. Connecting People with the Colne Valley

Aim: Involve people with their local waterbodies

The project aimed to encourage local people to discover wildlife in the Colne Valley through events, volunteering opportunities and new educational materials.

10. Hardings Row Millenium Nature Reserve

Aim: Improve wildlife corridors

Habitat enhancements and access improvements at this small nature reserve in Iver Heath

8. Springwell Reedbed

Aim: Improve wildlife corridors

Habitat restoration for wildlife. Improved site signage and interpretation.

7. Rickmansworth Aquadrome

Aims: Involve people with their local waterbodies; Improve wildlife corridors

Enhancments to Batchworth Lake and Bury Lake as part of site management plan implementation.

9. Route to the Colne Valley Park from Uxbridge

Aim: Involve people with their local waterbodies

Improve the paths from Uxbridge into the Colne Valley Park, its network of waterside paths and countryside attractions.

5. River Colne Backwater

Aim: Improve wildlife corridors

Backwater creation for mutual benefit of fishery and wildlife. To be undertaken as programme of habitat, access and landscaping enhancements along the River Colne walk

4. Colne at West Hyde

Aim: Improve water quality

Creation of backwater and in-channel habiat improvements - 0.2km

2. Frays and Colne weir

Aim: Improve wildlife corridors

Weir modifcation to provide fish passage. Next steps are feasibility study and detailed design

1. Grand Union Canal backwater

Aims: Improve wildlife corridors; Work together

Creation of a backwater for mutual benefit of the fishery and biodiversity. A fish refuge/spawning area and haven for wildlife with shallow sloping edges, variable depth, steep banks for Kingfishers. Tree works to increase light to the backwater to encourage growth of marginal vegetation. Habitat enhancements along the edge of the Grand Union Canal.