River case study

Hunts Green

River Lambourn

Lambourn (Hunts Green) – I

Project Brief

  • Restore an 800m reach of the Lambourn to favourable condition using cutting edge restoration techniques;
  • The installation of signal crayfish-resistant banks  was a key objective;
  • Create specific habitats for a number of target BAP species; and
  • Create a demonstration SUDS system to address runoff issues from a local highway.

Solution

A variety of Innovative, low-cost techniques were combined with signal crayfish-resistant materials  throughout the 800m reach. Sustainability and whole life cost benefits resulting from these techniques are a key project feature. The project was undertaken in three stages:

  1. Reinstate the coarse plan form within the over widened channel to kick-start essential fluvial processes.
  2. Installation of structures to the river bed and margins to  create specific in-channel features; i.e.detailed channel refinements to the crude channel form.
  3. The use of natural materials such as logs, brushwood and gravel to create specific habitats for key BAP species.
Lambourn river restoration

After Construction: October 2006 – Restored channel 4 months after completion.

Testimonial

” In 2006 Cain Bio-engineering was contracted via an English Nature management agreement with a local estate, to implement a restoration scheme on 800m of the river Lambourn at Hunts Green….in all cases the work was undertaken to a very high standard. English Nature was impressed with the ecological approach to river restoration offered by Cain Bio-Engineering Ltd coupled with engineering competency.”

“Their work with us has been characterised by high quality design and workmanship, delivered promptly and cost effectively. The results have been truly impressive”

DRM
Conservation Officer – English Nature

No formal monitoring was incorporated into the scheme, however ongoing follow-up visits suggest that the elimination of their bank side habitat is restricting signal crayfish distribution within the restored reach.

Read more about the history of Cain Bio-Engineering and its introduction to river restoration projects, across an impressive array of the UK’s most prestigious chalk streams and their tributaries.