Protecting Against Steep Slope Erosion and Failure

To guard against potential collapse due to steep slope erosion, Neoloy®Tough-Cells reinforced the slope while maintaining rural appearance.


45 and 70 steep slopes along main Highways A2 (A282 Dartford) and A3 (Hindhead) south of London were starting to collapse on new dual-carriage roads due to erosion. These slopes are exposed to a large amount of vibrations from heavy traffic on these highways. Requiring fast installation before winter, the client needed a low-maintenance solution that would protect the steep slopes from erosion. The solution also needed to blend in with the green forest scenery surrounding these highways.

Old Approach

One approach involves sand bags placed along the slope, which creates a non-aesthetic view from the road. Moreover, if damaged due to mechanical limitations (the bags are easily torn apart with a tendency to disintegrate in the sun), sand bags may fail to prevent the collapse of steep slopes.

PRS Neoloy Tough-Cell Solution

The client implemented a layer of large-size Neoloy Tough-Cell of 150 or 200 mm height over soil nailing with NeoClips anchoring, infilled with topsoil and suitable vegetation.

  • Superior protection of the slope from erosion problems
  • Aesthetic “green” solution preserving the road’s natural environment
  • Additional system stability from vegetation providing root lock-up
  • Rapid installation not requiring complex logistics – installed by a local contractor with minimum guidance from PRS engineers
  • Significant cost savings due to short installation time and less complexity – as much as 30% reduction in project installation time