Frequently asked questions about the Hunstanton Coastal Defence Capital Works
What are capital works and what is the difference between capital works and routine maintenance?
Capital works refers to major construction, refurbishment, or repair projects undertaken on a building or infrastructure. These projects often involve significant investment and focus on improving the structure. Routine maintenance is a proactive approach that includes regular surveys and scheduled works such as minor repairs to address problems before they escalate.
Why are capital works required?
A Geotechnical Report has recently been completed on behalf of the Borough Council by Concept Engineering. This report concluded that the current patch and mend repair approach is now not the most suitable approach to maintain the Hunstanton Sea Defences. The report recommends that: -
- Several sections of prom deck need to be replaced rather than patch repaired
- Some sections of sea wall need to be refaced (Sections E, F and G)
- Some sections of sea wall now require new or additional sheet piling to be installed (Sections E, F and G)
The report notes that there are two main reasons why capital works are now required further to the Hunstanton Coastal Management Plan being adopted in 2019. These are:
- Change in coastal process leading to erosion of beach material in front of the sea defences
- The concrete structure has reached the end of its designed life after being installed over 70 years ago
What is a Geo-Technical Survey?
These are site investigations that assess the subsurface conditions of the sea defences. In this case works undertaken included:
- Digging 25 trial pits in front of the sea defences to expose the conditions of the ground, foundations and material condition of the sea wall below the beach level
- A ground penetrating radar to assess the condition below the promenade deck
- A falling weight deflectometer to test the material strength of the concrete promenade deck
What works are required as part of this capital project?
The works will include:
- Replacing the existing concrete promenade deck, including filling any voids if found
- Refacing sections of sea wall (Sections E, F and G)
- Install new sections of sheet piling (Sections E, F and G)
How are the Hunstanton coastal defences currently managed?
Annual asset condition surveys are carried out which highlight what repairs are required to be completed to maintain the overall condition of the sea defences.
How long will this project take?
This will be a multi-year project. It is expected that the first 12/18 months will be project planning before starting a construction phase of at least another 12/24 months.
The next phase is to appoint a suitable civil engineering contractor who will lead on the detailed design of the new sea defence works. Once the design has been completed, we can then estimate the overall cost of the project. Once we have a completed design and costed it, we will then:
- Apply for sea defence grant funding from the Regional Flood & Coastal Committee
- Determine if planning permission is required, and if so, apply for planning consent
- Apply for a marine licence from the Marine Maritime Organisation
How much will this project cost and how will it be funded?
The overall cost will not be known until the detail design has been completed. A grant application for flood defence grant in aid will be made to the Regional Flood & Coastal Committee. The overall cost will likely be a multi-million pound project.
Are the coastal defences safe? Is there an increased flood or erosion risk?
The sea defences remain in a safe condition and are not structurally hazardous. This work is designed to maintain the existing flood defences going forward. There is no increase in flood risk or coastal erosion.
Why are you implementing a 10-tonne weight limit on the promenade?
A 10-tonne weight limit and 5 mph speed limit will be implemented on the promenade to mitigate against further deterioration of the promenade deck. Vehicle speed and weight can cause increased wear and tear to the concrete promenade deck, and therefore reducing speed and weight will reduce this impact until capital replacement is undertaken. The reduced speed and weight limit will need to remain in place until capital replacement works are undertaken.
What works / measures are you undertaking while the project planning phase is completed?
Routine asset condition surveys will continue, and any essential repairs will be carried out. Beach level monitoring will continue to be completed to measure how much beach material remains at the base of the sea wall.
A digital laser survey of the promenade will be completed every 6 months to check for any signs of subsidence.
A window sampling survey will be carried out to investigate the condition under the promenade deck.
What are your next steps / immediate steps?
- Update Stakeholders on the report findings and our next steps
- Engage a civil engineering contractor through the SCAPE Framework
- Start pre application work on sea defence grant in aid funding application
- Undertake monitoring
How does this project link with the review of the Wash East Coastal Management Strategy and recent Unit C Initial Assessment of the shingle ridge?
This project will maintain the existing sea defences, the strategy review will consider both Hunston Sea defences (Unit B) and the flood defences from South Hunstanton to Snettisham (Unit C). It will ultimately lead to updating the current Hunstanton Coastal Management Strategy which was adopted in 2019.
Are you engaging with relevant stakeholders on this project?
We will continue to provide regular updates on this project and our ongoing repair work through the WESMS Stakeholder Group, Local Sea Defence Newsletter and website updates.