Lyme Regis Cobb Stabilisation Scheme

The Cobb is a historic iconic harbour that provides a pivotal role as both a protective breakwater and a safeguard against erosion and flooding along the Lyme Bay coastline. In recent years, structural investigations have shown that the harbour is suffering from destabilisation caused by wave impact and sea floor erosion. The goal of this scheme is to reinforce and repair the harbour walls, ensuring that it continues its vital function for the bay and the local community and that its important heritage is safeguarded.

Project Update: 30 July 2025 – Cobb Wall Defect

Following an annual inspection of the seaward Cobb high wall carried out by Dorset Council officers in spring 2025, areas of further and ongoing deterioration have been identified with large open scour voids present at the base of the structure, at the Gin Shop turn. The void is located at an exposed section, thus Dorset Councils coastal engineers deem this repair to be urgent and required before the 2025/26 storm season. It should be noted that repair work is separate to the proposed Phase 5 scheme.

Overall, three asset defects have been identified and can be located on the image below:

1. Undermining at Gin Shop turn (urgent works required): Significant undermining has created a large void at the toe of the wall; 6m in length, 300mm in vertical opening, and more than 2m wide. This work will be prioritised for repair this year before the storm/winter season.
2. Southern Arm displacement (being monitored): There are indications of mass mortar loss, and minor undermining of the toe, both within the visitor harbour section. These defects are being monitored and structural inspections have been undertaken.
3. Cobb Building seawall (being monitored): The seaward wall has mass grout loss, missing blocks and overhanging blocks. This section of the Cobb is primarily a foundation structure for the commercial buildings. These defects are being monitored and structural inspections have been undertaken.

Cobb repair works, what happens next?

• Dorset Council engineers are progressing potential repair options with the support of specialist consultants.
• The repair work is estimated to cost between £300,000-350,000. Dorset Council funding for this work is being sought and is currently under review.
• A specialist engineering consultant has been procured. The consultant will review and recommend works to repair the void at the Gin Shop turn. They will then prepare a scope of works for remediation and assist with the procurement of a specialist contractor as well as supervise works on site.
• Dorset Council intend to progress any construction works before the start of the winter storm season.

What is happening with the Cobb Phase 5 Works?

• In addition to the repair works, plans continue for Phase 5, the Cobb stabilisation scheme. The key challenges are gaining appropriate advice from Historic England and identifying further funds to pay for the works.

Historic England Advice

• The project team are continuing discussions with Historic England for pre-application service advice and are still awaiting feedback following submission of further supporting evidence by the project team. It is vital that agreement with Historic England is reached prior to procuring consultancy services for detailed design. Their support is crucial not only for planning purposes but also for enhancing the likelihood of successfully securing external funding.

Funding

• In June 2025, the government launched a consultation ‘Reforming our approach to floods funding’ that sets out proposed changes to coastal defence funding via the Environment Agency. The principles of the reform proposals provide an opportunity for Dorset Council to apply for additional government funding to alleviate the funding shortfall, following reforms taking place in 2026. Once decisions on planned funding allocations are known, the project team shall assess the impact of any changes to the project.

Proposed timelines

• Dorset Council are planning to submit the necessary planning applications for construction in Summer 2026, to start building between Winter 2026 and Spring 2027, subject to progress of consenting applications and funding availability.

Engagement and Communication

• The project team will keep you updated with quarterly project updates on this page and update the Harbour Consultative and Advisory Groups. Plus, Dorset Coast Forum will be organising public engagement and awareness sessions in October or November, to keep everyone informed.