8151 Slope protection and erosion control (0) Work and systems to protect slopes from environmental affects (water, drying, freezing) and physical affects (natural and non-natural loadings and wear). Work and systems to control erosion from affects of wind and water (flows and flooding). Includes, membranes and fabric reinforcing, sprayed concrete or other material etc. 8152 Earth and rockfall protection walls (0) Walls located downhill of slopes to restrain or prevent earth movement and rockfalls from progressing further. 8153 Riprap protection (0) Stones placed to prevent fast water from scouring and eroding a surface or channel drain