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.