Stopping the Slide

The cliffs at Overstrand were already protected with a timber revetment, to take the force out of the waves, and groynes, to retain beach material. However, landslides were still happening and if the houses on Clifton Way were going to stay on Clifton Way and not finish up on the beach then something else needed to be done.

Once the early warning system was in place, attention was turned to the beach. Working carefully, and in small sections so as not to unstabilize the slope, the loose debris forming the toe of the previous landslide was removed and replaced with rock armour!

That already sounds better doesn’t it! Rock armour consists of large boulders of strong, hard rock.

The boulders have interlocking crystals which are much more resistant to the pounding of waves than the debris of the landslide or the loose sand and clay of the cliffs.

On the landslide slope itself drainage was improved. Too much water in the ground lubricates everything and helps it to slip more easily, so channels were created to help excess water to drain away.

Finally, the surface was compacted to reduce water penetration from rainfall and the site was left for vegetation to re-colonise.

So, has it worked? Well seemingly, yes. The houses on Clifton Way are still on Clifton Way and Clifton Way is still on top of the cliffs. There has been no significant change since 1995 so confidence has gradually returned, and house prices have risen.

But the sea continues to pound, and the rock armour won’t last forever, so monitoring will be required. Fortunately, the early warning system is still in place.