Erosion in Ocean Bay

Ocean bay is situated to the north of Swanage Bay. Ocean bay suffers from erosion and since the new flood alleviation scheme outfall was built along the main sea front the beach at Ocean Bay has vanished at high tides and large sections of the cliff has fallen away into the sea. The largest section is shown below and is over 100 meters wide

The cliffs at Ocean Bay are composed of clay and sandstone in the southern part, and chalk to the north. The photos below show the cliff area at th north end of Swanage bay, the photograph on the left was taken before the flood alleviation scheme outfall was built the the photograph on the right shows the land slides and erosion of the beach, this picture was taken 2000/2001 winter.

Photograph taken early 1980s Feb 2001 March 2014
     
The photo below shows the erosion at steps below Ballard Estate, locally known as Sheps Hollow, Until the winter of 2000 you could access the beach via the steps down the side of the cliff at this point but due to the excessive cliff falls and erosion on the beach, the steps have completely fallen away and it is far too dangerous to attempt to leave the beach at this location. The steps have since been rebuilt but there are still often landslides in the area and the cliffs are unstable.
     

Steps in 2014
Photograph taken early 1980s Damaged Steps Feb 2001 Steps in 2014
     

Erosion in Durlston Bay

Erosion of the Swanage and Purbeck Coastline

Durlston Bay is situated to the south of Swanage, in the most south-eastern corner of the Isle of Purbeck. The bay is smaller than Swanage Bay and has a shingle beach which is derived from the more resistant strata (mainly limestones) that outcrop in the surrounding cliffs.

The name Durlston means "pierced rock" and the bay is believed to be named after the blow hole that was covered up near the end of the 19th century. The bay was heavily quarried throughout the 19th and 20th centuries, with many tunnels dug into the cliff faces. Most of these tunnels have since been covered by land slides which regularly occur in the bay.

To the north of Durlston Bay and separating it from Swanage Bay is Peveril Point. This stone headland is formed of a hard bed of limestone (known as Purbeck Marble) which runs from Herston to the west of Swanage to Peveril Point and then eastwards under the English Channel. The small building on Peveril Point is currently used by National Coastwatch as a lookout.

Throughout the second half of the 19th century, Peveril Point was a base for the Dorset Artillery Corps who were a part of the voluntary force that made up Britains home defence. The Corps built a fort on the headland which contained two, thirty-two pound cannons which fired 6.4 inch balls.

In 1886, Durlston Castle was built by George Burt as a monument for the town. The castle, built on Durlston Head, is currently used as a restaurant and bar. The corbel-turreted building is built completely from local stone. Surrounding the castle are stone tablets inscribed with various statistics and poetry which reflect the Victorians interest in the sea and the forces of nature.

The area in and around Durlston Bay is prone to landslides. Many small slides occur every year but with larger slides may occur after periods of extreme weather. The slides are normally caused by heavy rain which causes water to run along the clay layers in the strata. This lubricating effect can cause the rocks above to slip down towards the sea. The cliffs in Durlston bay are made up of a alternating clays, limestones and shales and this is a key factor in terms of the areas instability.

One large fall that occurred caused 1000s of tons of earth and rock to slide down the cliff into the sea. It happened near a block of flats which are now only metres away from the unstable cliff edge.

(a landslide in the centre of Durlston bay).

(The landslide is threatening to destroy a large block of flats that are situated at the top of the cliff).

The southern Purbeck Ridge starts in Durlston Bay and runs west

We would like to thank Mr Malcolm Turnbull for the information on this page.