Case study:River Wensum Restoration, Reach 10 Lenwade
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Project overview
Status | Complete |
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Project web site | |
Themes | Habitat and biodiversity, Hydromorphology |
Country | England |
Main contact forename | Amy |
Main contact surname | Butcher |
Main contact user ID | User:Amy.butcher |
Contact organisation | Environment Agency |
Contact organisation web site | http://www.gov.uk/environment-agency |
Partner organisations | |
Parent multi-site project | |
This is a parent project encompassing the following projects |
No |
Project summary
Reach 10 of the River Wensum Restoration Strategy involved restoring 1.3km of SSSI & SAC designated river at Lenwade, west of Norwich, Norfolk. Improvements to morphological diversity were achieved here through the installation of woody material features, bank stabilisation, hinging willow trees and re-engineering the existing gravel bed to create riffles and pools. Selective tree felling also took place to allow light into a heavily shaded area of the channel.
Monitoring surveys and results
Analysis of monitoring results pending.
Lessons learnt
Access was very limited due to the presences of fishing lakes adjacent to the river. Most works had to be completed by hand. Some work was carried out by amphibious excavator where the benefits outweighed the potential damage to the gravel bed from the excavator tracks.
Additional tree works were required due to periods of high winds and the need to make the area safe for construction work to be carried out.
Re-profiled river banks with bare soil were exposed during high flows and could have lead to erosion and sediment input. Seeding and the installation of a biodegradable jute matting was carried out to minimise erosion. (This had not been anticipated in the design. Ideally work would be carried out early enough to allow bank vegetation to re-establish from the existing seed bank.)
Image gallery
Catchment and subcatchment
Site
Project background
Cost for project phases
Reasons for river restoration
Measures
MonitoringHydromorphological quality elements
Biological quality elements
Physico-chemical quality elements
Any other monitoring, e.g. social, economic
Monitoring documents
Additional documents and videos
Additional links and references
Supplementary InformationEdit Supplementary Information
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