The Sidmouth Coastline


What is the geological composition of the coastline around Sidmouth?



The coastline displays a varied geological profile. In the west, the cliffs primarily consist of Triassic red beds, specifically Otter Sandstone and younger Mercia Mudstone, often capped by Upper Greensand and Chalk (though much of the Chalk is eroded). Moving east, the geology continues to feature Mercia Mudstone overlying Otter Sandstone, particularly evident at Pennington Point and Salcombe Hill Cliff. Salcombe Hill and other eastern cliff tops are also capped by Upper Greensand, with some areas retaining small patches of Chalk. 

How does the beach composition vary along the Sidmouth coastline?



The beach composition changes significantly along the coastline. To the west of Jacob’s Ladder, there is a substantial shingle beach. Eastward from Jacob’s Ladder, the shingle gives way, and a walkway is present. Around Connaught Gardens, the shingle beach returns, and an extensive area of sand is exposed at low tide. The eastern section of the beach, including East Beach, is primarily composed of flint and chert. 

What significant rock formations and features are found offshore near Sidmouth?



Offshore near Jacob’s Ladder are the Chit Rocks, remnants of a prominent Otter Sandstone feature that was significantly reduced by a storm in 1824. Further east, constructed around 1994 as part of coast protection efforts, are two rock ‘islands’ made from granite and larvikite.

How does the River Sid interact with the sea at its mouth, and what are the implications?



The River Sid's mouth experiences dynamic changes influenced by the tides. High tide brings sediment in, impeding the river's flow, while at low tide, the river erodes this sediment to resume its normal course. After storms, a substantial shingle barrier can form at the mouth, causing the river to back up significantly upstream.

What historical features can be found along the eastern part of the coastline?


An interesting historical is the breached remnants of the Sidmouth Tunnel, an old 19th-century railway tunnel system dug behind the cliff face east of the Alma Bridge. This tunnel was originally protected by shingle but has become exposed due to coastal changes.

Why is access restricted to the beach in the eastern section of the coastline?



 Access to the eastern section of the beach, including East Beach, is currently closed to the public for safety reasons. This is primarily due to the danger of rock falls from the cliffs and the reduced beach area, which means the sea reaches the base of the cliffs at high tide, posing a risk of people being cut off. 

How has coastal protection been implemented in the Sidmouth area?



Coastal protection measures have been implemented in the area. One notable example is the construction of two rock ‘islands’ offshore near Connaught Gardens in 1994, using a significant quantity of granite and larvikite, as part of the Sidmouth Coast Protection Scheme. Additionally, large granite boulders have been placed along the foot of the cliffs east of Jacob’s Ladder to protect the walkway there.

What are some of the key characteristics of the Mercia Mudstone found in the eastern part of the coastline?



The Mercia Mudstone in the eastern section, specifically between Salcombe and Weston Mouths, is noted to contain gypsum and potato-stones. This geological formation is also prone to erosion and rock falls.