Marple Brook Improvement Works
The immediate Dan Bank area around Marple Brook is designated a site of Special of Biological Interest. This is due to the diverse flora & fauna, and the up-slope woodland is designated as ‘Ancient Woodland’. The project was planned to ensure minimum disruption to the immediate environment. Works were regularly monitored by independent ecologists appointed by the client.
These works were designed to improve the natural subsoil drainage of the slope and promote less silting and better water flow in Marple Brook at its base. The site was highly inaccessible with steep slopes on all sides. Therefore much of the work was undertaken manually or with very small items of plant equipment.
New land drainage wrapped in geotextile and covered in lime-free gravel was installed from the banks of the Brook. It was laid by hand along the 50 metre height of the steep slope to the main road. Separate drains, catch pits and silt traps were also installed to catch the surface water run-off from the road gullies. All works were executed without disturbing several badger setts which exist on the embankment.
Marple Brook was cleaned out and the embankment toe stabilised with timber stakes, barge boards and pre seeded coir logs. Seeded Coir matting was also laid in sections adjacent the brook to assist the establishment of grass, as a deterrent to soil erosion. Further scour protection measures were undertaken involving imported stone rip-rap material placed strategically at bends in the watercourse. Small timber weirs were installed in the brook bed to accrete silt and stop erosion to the downstream.