The Changing Shoreline

Why is the Sidmouth coastline changing?



The Sidmouth coastline is naturally changing due to the constant erosion of soft sandstone cliffs by the elements. These natural processes are exacerbated by climate change and, arguably, the unintended consequences of past human interventions, such as the rock islands built at the end of the 20th century.
 

What are the main impacts of coastal change in Sidmouth?

 
The main impacts are collapsing cliffs, disappearing beaches (particularly the Main Beach), and occasional flooding of the low-lying town centre. The shrinking Main Beach reduces the protection offered by the sea wall and increases the risk of overtopping during storms.
 

Have past human interventions affected the coastline?

Yes, past engineering works, specifically the rock islands built at the end of the 20th century, have arguably had unintended consequences, such as increasing erosion of the east beach and cliffs.

What is the current erosion rate of the cliffs near clifftop homes?

Recent research estimates an erosion rate of at least two metres per year, which is significantly higher than previous estimates. This suggests that heavy erosion could claim clifftop homes within 20 years.

How does the shrinking Main Beach contribute to flooding risk?

 
The shrinking Main Beach provides less protection to the sea wall. This increases the risk of 'overtopping' during storms, where large volumes of water are thrown over the Esplanade and flow into the vulnerable, low-lying town centre.

What is the preferred option for managing coastal erosion in Sidmouth?

The preferred option includes implementing the Beach Management Plan. This involves engineering works such as installing a new groyne on East Beach, raising the splash wall along the promenade by up to a metre, and importing shingle onto both East Beach and Sidmouth beach. The aim is to maintain a healthy beach to reduce overtopping.
 

What are the broader, national trends in coastal management?

Nationally, management policies are increasingly moving towards long-term sustainable solutions rather than solely 'hold the line' approaches. Managed realignment, which allows natural processes like erosion and accretion to function while potentially creating new habitat inland, is one such approach being considered more widely.
 

What is the overall goal of the Beach Management Plan for Sidmouth?

The overall goal is to actively manage the changing coast and the risks posed to properties and infrastructure. This involves implementing the proposed engineering works to maintain beach levels and reduce the risk of flooding, while also considering broader strategies for adapting to ongoing coastal change based on research.