are in place for some parts of the region. But knowledge of the geotechnical risks of the area has not prevented another tragic disaster.
When water is introduced, the water pressure pushes soil particles apart, reducing this strength. Also some soils, such as clays, are more slippery and present an even greater landslide risk.Greater eThekwini geology The sands of the Berea formation were subject to intense investigation in the late 1950s following landslides. The strength of the Berea sands was not uncharacteristic for sandy material. But the Bluff slopes were steeper than would be expected based on the soil’s strength. The only reason the slopes hadn’t collapsed was that plant growth was reinforcing the soil.
The reason is that as the Berea sands have little to no clayey stickiness, or plasticity, they are extremely prone to erosion. When large torrents of water flow over the sands they simply erode to formInland from Durban are shales of the Pietermaritzburg formation. They dip down from their main exposure in the inland city of Pietermaritzburg towards the sea at Durban.
There's also cloud seeding.