Case study:River Wandle: Butter Hill Phase 3
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- 1 Project overview
- 2 Image gallery
- 3 Catchment and subcatchment
- 4 Site
- 5 Project background
- 6 Reasons for river restoration
- 7 Measures
- 8 Monitoring
- 9 Additional documents and videos
- 10 Additional links and references
- 11 Supplementary Information
|Project web site|
|Themes||Fisheries, Habitat and biodiversity, Social benefits, Urban|
|Main contact forename||Tim|
|Main contact surname||Longstaff|
|Main contact user ID|
|Contact organisation||Wandle Trust|
|Contact organisation web site||http://www.wandletrust.org|
|Partner organisations||Environment Agency, Defra, Thames Water, National Lottery's Heritage Lottery Fund|
|Parent multi-site project|
| This is a parent project
encompassing the following
This Project is part of a larger scheme with the overall aim of establishing a population of brown trout in the Carshalton arm of the River Wandle for the first time in over 80 years. For more background on this larger scheme, please refer to the parent project "River Wandle Restoration Project".
Flood risk and hydraulic assessment of the weir and fish pass were carried out in conjunction with Matt Horritt Consulting. Works were delivered with the help of appointed contractors Aquamaintain Ltd under the supervision of South East Rivers Trust staff. The weir at Butter Hill bridge was partially lowered to restore natural flow to the upstream channel and the fish pass modified to improve its efficiency.
Upstream of the weir the over-straight, over-wide channel was narrowed and modified to create a meandering sequence using a combination of gravel, hazel faggots, chestnut posts and coir geotextile with silt from the channel and brash as backfill. The banks on both sides of the channel were then re-graded to create marginal and transitional habitats. A variety of marginal plant species were introduced to assist with naturalisation by a team of 15 volunteers.
Downstream, for 300 m, channel narrowing and meandering was continued and gravel and Large Woody Debris was introduced along the whole reach to further diversify the river flow and replicate natural hydromorphological processes, creating habitats for invertebrates and all life stages of fish.
Trees were also removed in phases over a two year period to increase light in selected places and encourage plant growth along the whole 500 m reach.
Monitoring surveys and results
Please see the parent project (River Wandle Restoration Project) for the final results on this work, combined with the other phases.
Catchment and subcatchment
Select a catchment/subcatchment
Cost for project phases
Reasons for river restoration
Hydromorphological quality elements
Biological quality elements
Physico-chemical quality elements
Additional documents and videos