Langstone, Mill Pond to Wade Lane, Havant

Project Update

There are shared concerns about the condition of this coastline, which is a valued location in the borough. In March 2022 following winter storms, an approximate 30m long section of brick seawall collapsed. Havant Borough Council continue to monitor this situation, liaising with Chichester Harbour Conservancy and Hampshire County Council, Countryside Services Team (HCC) on the safety of the public footpath that runs along the top of the defences. There are 3 main areas of damage as shown on the location plan and in the photos below.

Area 3: Collapsed section of seawall

The walls are historic and there is evidence of previous patch repairs. The section enclosing the Mill Wall is anticipated to be a front face to an earth or clay containment for the pond, while the collapsed section appears to have been a single skin earth retaining structure. An assessment of the overall condition of the sea defence is generally poor. Un-maintained, there is a risk of further collapse of the wall in this location.

The field behind these walls experiences flooding at times of high water flow to the Lymbourne Stream, and during high tide events when the sea water overtops the wall. Historical mapping dating from the old Ordnance Survey County layers mapping (1840-1880s) shows the course of a drain around the east of the Mill Pond, indicating previous land drainage to this area. Maintenance of the Lymboure stream by the riparian owners can help alleviate the levels of field flood: Flood Risk Management Guidance for Landowners.

Together, Havant Borough Council (HBC), Chichester Harbour Conservancy (CHC), Hampshire County Council (HCC), Natural England (NE) and Environment Agency (EA) agreed upon a Statement of Common Ground. This sets out that the partners agree to the following priorities in the medium term: 

• Maintenance of the Mill Pond wall, and
• Maintenance of the coastal footpath along its current route by construction of a footbridge towards Wade Lane. 

To read the full statement click here

Maintenance of the Mill Pond Wall

This priority is led by Havant Borough Council. RHDHV was commissioned to undertake professional design services for the maintenance of Mill Pond wall. Recently the consultant has produced a design, specification, and cost estimation report for all the defects.

Each defect was prioritised based upon depth of the void or gaps n the mortar, and its height in the wall relative the tidal levels. Works can then be scheduled based upon affordability and failure risk. There are 3 costed scenarios:

The council allocated £30,000 of capital investment for this maintenance, the cost estimates indicates a further £80,000 is needed to implement the least cost option. High costs are associated with the difficultly of access, manual working methods and the waterside working.

A funding bid will be made to the Council for this value. Annual budget setting process begins in September and is likely to be finalised in February. With this in mind the Council will monitor the wall closely over the winter and following any storm events to check for further deterioration.

Maintenance of the Coastal Footpath

Chichester Harbour Conservancy, with the support of Hampshire County Council (HCC) are leading on the construction of a footbridge to span the area of erosion where the wall has already collapsed. The footbridge enables the footpath to remain on the current alignment and maintain the coastal access. HCC are designing the bridge and currently undertaking the necessary ground and site investigations. 

A decision on whether the bridge can be installed in the current financial year is yet to be made, this will be dependant on budget estimates, the proposed work method and any site conditions that may be found during this initiation stage. 

Previous progress

In June 23 Havant Borough Council resolved that the council would write to the Environment Agency, Chichester Harbour Conservancy and Natural England to express the strong democratic support for the protection of the Langstone Mill Pond through sea defences. The full responses can be read here: Read the full responses here

In July 2023, an independent report was commissioned into options for the future of the failing sea defences at the bottom of Wade Lane, near Langstone Millpond. The consultants Royal Haskoning DHV are experienced in coastal management solutions. The report provided an assessment of the sea defences and surrounding area, and advised on their future management.

The consultants, finalised the report in October and it can be read in full here.

In September a response to the Leader of the Council's letter was received by Rebecca Pow MP, the then Minister for Environment, Quality and Resilience. This letter is also to be considered a response from Lord Parkinson of Whitley Bay. The letter can be read in full here.

A public drop-in session was held on the 12th of December with representatives from Havant Borough Council, Coastal Partners, Natural England, Chichester Harbour Conservancy and Royal Haskoning DHV on hand to answer any questions. The event was well received and visitors obtaining information about the constraints, the longer term environmental adaption and the response anticipated in the area.

In January 2024 Havant Borough Council chaired a meeting with the consenting organisations Chichester Harbour Conservancy (CHC), Natural England and Environment Agency. This meeting together with many other meetings confirm the organisations’ collaborative approach to reach a solution for this area of public concern. 

Next Steps

Coastal Partners will continue to monitor the defects closely and frequently. We have been surveying the erosion of the land affected by the collapsed seawall in Area 3 since December 2022.

Coastal Partners will make a capital bid for additional funding to enable implementation of the Maintenance works to the Mill Pond Wall. 

Hampshire County Council will undertake site investigations to enable the bridge design to be carried out and costs for supply and installation to be estimated. 

This is not an isolated challenge in Chichester Harbour and there are other sites within our harbour with failing sea defences, where maintenance or replacement of defences is no longer the best option and is unlikely to be consented. Solving the complex challenges such those described above for Wade Lane drive a need for a Chichester Harbour Wide Strategy to develop a holistic way forward for people and the environment, providing the much-needed direction for areas like Langstone Mill Pond. HBC are in the process of bidding to the Environment Agency for funding to develop the works to local needs and the government vision for a nation ready for and resilient to flooding and coastal change - today, tomorrow and to the year 2100.