Treboeth Cobble Channel

Treboeth eroding cobble bed channelTreboeth post-installationTreboeth two months laterTreboeth one year later
Treboeth eroding cobble bed channel

A new development had slope stability issues due to an adjacent cobble bed watercourse badly eroding the soils and downcutting the bed within the channel. The steep channel gradient had a very flashy, aggressive flow regime. Salix were recommended to the developer by a previous client to provide design & build solution.

A more cost effective, sustainable alternative to blockstone was proposed using a turf reinforcement matting (TRM) called VMax C350 on the re-graded slopes.

Vmax C350 is a UV stabilised permanent TRM that reinforces the vegetation on the banks allowing the grass to take flows of up to 6m/sec without soil loss.

Rock Rolls were installed at the toe to withstand the abrasive action of cobbles and gravels under flood conditions, with a living element of a pre-established Coir Roll containing native marginal plant species to encourage plant growth through the Rock Rolls.

Rock Rolls are a flexible system, pre-filled off site with small stone that allows accretion of sediment and roots to grow through and also allow movement of benthic invertebrates within the riparian zone and water.


Name: Treboeth Cobble Channel
Client: Private Developer
Location: Swansea
Category: High Energy Rivers, Rivers & Water Courses

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Case Study

Treboeth Cobble Channel Case StudyDownload 

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