Salix were invited to submit a bioengineering solution to solve an erosion issue at a pipeline crossing in West Wales. The solution used a combination of locally harvested willow and Rock Rolls to provide a stable revetment in this cobble bed river.
Salix were asked by Main Contractor NACAP Land & Marine to assess the potential for using a bioengineering solution to control the eroding riverbanks.
The erosion was an existing issue prior to the pipeline crossing and initially a blockstone revetment was considered. However, consultants from Salix were confident that a bioengineering solution could work in this instance.
The bioengineering design solution used locally harvested willow material used as live stakes and the thinner branches used to form live fascines (faggots).
A double Rock Roll was placed at the toe to prevent the willow plantings from being undercut and to protect against abrasion from the mobile gravel/cobble bedload.