The Langstone Coastal Defence Scheme
January 2024 Exhibition Poster Booklet
Welcome
To the Langstone Coastal Defence Scheme
Langstone The historic village of Langstone sits at the southern tip of Havant where Hayling Island meets the mainland. The current coastal defences that line the compact and pretty village are in a poor condition with some nearing the end of their life. With critical upgrades needed, a scheme is being developed that will protect Langstone for the next 50 years. Coastal Partners on behalf of Havant Borough Council welcome you to this public exhibition on the Detailed Design of the Langstone Coastal Defence Scheme. This is the latest and most detailed vision of the design proposals which have been developed with the Community and other Key Stakeholders.
Aerial view of Langstone The design has now reached a major milestone. Together with your feedback, a recommendation will be made in 2024 to HBC Cabinet to proceed to the licencing and consenting stage (including submission of a full planning application). Construction is then programmed for Spring 2025. When completed, the upgraded defences will stabilise flood and erosion risk to 63 homes and businesses. Critical infrastructure will also be protected, alongside important heritage and landscape assets. Coastal access and recreational opportunities will also be improved, and the natural environment will be preserved and enhanced.
We’d like to hear your views This event is an opportunity for you to share your support for the scheme, and any areas which you think need further improvement. Please take your time to read the information boards which cover the key design aspects. You may also want to view the latest before and after visualisations which are being projected onto the wall. The Project Team are here to bring the scheme to life. We’d love to discuss any queries you may have. We also have a range of samples of materials which are proposed for the scheme.
Langstone High Street
There is a survey form to fill in to record your thoughts if you can drop it in the feedback box at the exit.
havant.gov.uk coastalpartners.org.uk
Langstone Today LOCATION
KEY FEATURES
AMENITY & RECREATION
The village of Langstone is located immediately north of Hayling Island in the Borough of Havant, Hampshire. The A3023 passes through Langstone to Hayling Island.
The frontage is popular with locals and visitors due to its unique setting and is an important area for cultural heritage, with six listed buildings and two Conservation Areas (Langstone and Mill Lane).
There is a network of footpaths, which also features the historic Wadeway, Solent Way and Hayling Billy Line (which also doubles as a cycle route). There are also two pubs in Langstone (the Royal Oak and the Ship Inn) and the harbours are popular for watersports.
Mill Lane & Harbourside A3023 Langstone Road Langstone High Street The Royal Oak
Langstone Harbour
Hayling Billy Line
Langstone Rowing Club
The Ship Inn
Langstone Spit
Langstone Sailing Club
Chichester Harbour
Historic Wadeway from Langstone to Hayling Island
Environmental Features The village of Langstone is bordered to the west and east by Langstone and Chichester Harbours; vast areas of important intertidal habitats providing enhanced ecosystem services.
Internationally important populations of rare wildfowl and wading birds visit during the winter. Local highlights also include breeding locations for Little Egret, the first location in the country where these birds bred outside of an existing heronry. The harbours contains areas of saltmarsh, mudflat and eelgrass habitats that support bird species alongside fish and marine mammals (including common and grey seals).
These habitats are internationally protected and the harbours are environmentally designated as a: • Special Protection Area (SPA)
We have undertaken a variety of ecological surveys including intertidal and terrestrial habitats, reptiles, trees, bats, badgers and breeding and over-wintering birds to better understand the value of these habitats
• Special Area of Conservation (SAC) • Wetland of International Importance (Ramsar Convention) • Site of Special Scientific Interest (SSSI)
havant.gov.uk coastalpartners.org.uk
The Challenges Tidal Flood Risk Located on the fringe of the two harbours, Langstone village is susceptible to tidal flooding, especially during periods of extreme weather, but also on normal high tides.
Present day Flood Risk Flood risk modelling highlights that for the present day there are 73 residential properties at risk of flooding from a 1 in 200 year (0.5% Annual Exceedance Probability (AEP) tidal flood event. There are also four non-residential properties at risk of flooding from the same return period event. A 1:200 year event is a statistical flood event with a probability of 0.5% probability of occurring in any year (Annual Exceedance Probability [AEP])
A Changing Climate Chichester and Langstone Harbours are facing growing challenges from climate change, where sea levels are rising, storms are becoming more frequent and extreme, and coastal flood and erosion risk is increasing. Over the next 100 years, over 120 homes in Langstone are at risk of tidal flooding in an extreme event.
Aerial photography © Channel Coastal Observatory (2021)
Infrastructure at Risk Should the A3023 be inundated by the sea at Langstone, the one and only road transport link to Hayling Island will be disrupted and the island would be ‘cut-off’ from the mainland for a period of time.
The flooding that we see today during extreme events is likely to become the new normal.
This also has implications for the health and safety of residents on Hayling Island because emergency service access to the island would be restricted or severed. With climate change and sea level rise the occurrence of such events is set to increase significantly.
Langstone Path
Car Park at The Ship Inn
Quay at The Ship Inn
havant.gov.uk coastalpartners.org.uk
The Challenges Ageing Coastal Defences The existing defences at Langstone consist of a mixture of concrete walls, concrete block revetments and masonry quay walls, which are in a poor and degraded condition. Structural surveys undertaken during detailed design have confirmed that these structures are reaching the end of their serviceable lives. Some of the existing structures do not have registered landowners making maintenance responsibilities more complex. The existing structures are becoming increasingly hard and costly to maintain into the future. If we don’t address this issue now, the structure will eventually fail, health and safety will be an issue. Therefore, a better, longer term, sustainable solution is required for future management.
Quay Walls at The Royal Oak, Langstone
Heritage at Risk of Erosion The landscape of Langstone is unique and boasts a rich history, which is highly valued by the community. Buildings at the water’s edge are vulnerable to coastal flooding and erosion, now and in the future despite a history of existing in harmony.
Storm Barra, 2021
Environment Under Pressure The natural environment of Langstone and Chichester Harbours has suffered from increasing pressures. There has been a decline and squeeze of important intertidal habitat such as saltmarsh, alongside reduced water quality. This in turn impacts already fragile coastal ecosystems.
The condition of the existing flood defences is key, and without remediation, coastal erosion could lead to a sudden failure of these structures and loss of heritage features. Intervention in the form of a scheme will serve to protect heritage assets in Langstone more than doing nothing – a scenario where heritage features would be lost to erosion and flooding. Historic buildings and structures were often built to last but are unlikely to have considered rising sea levels and ability to withstand more frequent wetting and drying (especially of timber structures). A flood risk reduction scheme will help to preserve and extend the life of these features.
In order to protect and enhance biodiversity there are regulations in place, which require assessments of development proposals, including coastal defences. Reducing flood and erosion risk to property and important infrastructure (like the A3023) is an ‘imperative reason of overriding public interest’ (IROPI), but it must be demonstrated there are no feasible alternative solutions which are less damaging, and further environmental improvements will be required in order to deliver biodiversity net gain. This has been accounted for within the proposals
Foreshore at Langstone
havant.gov.uk coastalpartners.org.uk
The Langstone Scheme
NORTH SOLENT SHORELINE MANAGEMENT PLAN Adopted in 2010, this high-level policy document recommends a ‘Hold the line’ policy to maintain or upgrade the coastal defences
The Langstone Flood and Coastal Erosion Risk Management (FCERM) Scheme (hereafter referred to as ‘the Scheme’) is required to protect a significant number of people, property, businesses and other key assets from coastal flooding and erosion.
PORTCHESTER CASTLE TO EMSWORTH STRATEGY
Following approval by Havant Borough Council in 2018, a project team formed and secured funding to undertake the Options Appraisal and Outline Design stage of the scheme setting out on a path to prepare designs for a feasible scheme. We have now reached the end of Detailed design and are pausing to share the Scheme proposals with you at this exhibition.
The Strategy looks at how the SMP policy can be implemented at a more local level and identifies areas where work may be required over the next 100 years. The Strategy recommended improvement of the defences at Langstone through a phased approach
OPTIONS APPRAISAL Structural and ground investigations Community engagement
A robust options appraisal has been completed supported by extensive stakeholder engagement. The leading option for each frontage was taken into outline design
OUTLINE DESIGN
Outline Design public exhibition
Outline Designs were finalised for a Scheme in 2020 We are here
Detailed Design Public Exhibition
HBC Cabinet decision to proceed with consent applications
HBC Cabinet approval to proceed with Detailed Design
DETAILED DESIGN
Licencing and consenting Funding strategy Pre-construction engagement HBC Cabinet decision to proceed with Construction
2018 HBC Cabinet approval to proceed with Option Appraisal and Outline Design
Detailed design commenced in 2020. This developed the outline designs further, seeking optimisation and feedback from the community to shape the final look and feel of the design
CONSTRUCTION
Scheme Delivery and Operation
The leading option is to construct a variety of defences along the frontage to provide a scheme with a 50-year life. The Scheme will provide a standard of protection (SoP) of 0.5% Annual Exceedance Probability (AEP) (1 in 200 year event) present day, which will reduce to 1 in 75 years SoP over the 50-year life. The SoP provided by a defence is the severity of flood event that it should protect against.
havant.gov.uk coastalpartners.org.uk
Who is Involved?
PROJECT TEAM We are a team of specialist council officers and engineers who deliver a comprehensive coastal management service across 246km of coastline. As part of Havant Borough Council we are managing the delivery of this coastal project.
AECOM are an engineering consultancy, helping us deliver the more technical elements in the role of Designer. AECOM are experts in this field having developed designs for similar coastal management schemes around the country.
SPECIALIST PROJECT SUPPORT
Specialist Heritage and Archaeological Support has been provided by Wessex Archaeology during detailed design.
Specialist Cost Consultation services have been provided by Faithful and Gould. This has improved cost estimations throughout detailed design.
Independent Arboricultural advisor to support understanding of any impact of the scheme on trees. Early Contractor Involvement has been provided by Mackley, who have provided practical advice on the buildability of the detailed design proposals.
KEY PARTNERS AND CONSULTEES
Havant Borough Council have invested Community Infrastructure Levy towards scheme costs and are a major stakeholder in the project as Client. HBC are also the Local Planning Authority.
The Environment Agency have invested Grant in Aid Funding towards the scheme towards reduced property flood and erosion risk.
Hampshire County Council is the Highways Authority, and a key project stakeholder with landowner and manager interests, also investing in the project.
Natural England regulate and advise on matters of environmental impact and have interest in the project due to its proximity to designated areas.
LANGSTONE STAKEHOLDER WORKING GROUP The LSWG is a group of key community stakeholders and representatives who have met at key milestones to explore the proposals and help to build consensus and support for a Scheme through providing feedback.
COASTGUARD C O T TA G E S RESIDENTS
LANGSTONE FLOOD WATCH
LANGSTONE VILLAGE
ROYAL OAK FRONTLINE COTTAGES GROUP
A S S O C I AT I O N
MILL LANE & HARBOURSIDE SEA DEFENCE GROUP
LANGSTONE CONSERVATION GROUP
THE COMMUNITY The Langstone Community has been key to developing appropriate and considerate designs.
We have held various well attended stakeholder and wider public events over the years and have listened to feedback received to shape the design proposals and build support for a Scheme in Langstone
havant.gov.uk coastalpartners.org.uk
You Said, We Did!
We use the Billy Trail Cycle path but it is narrow in places and the surface is in poor condition
The Langstone Community and Stakeholders have been key to developing appropriate and considerate designs.
We have been working with Hampshire County Council to incorporate a wider 3m cycle path with new tarmac surface
We have held various well attended community events over the years and have listened to feedback received to shape the design proposal
We would prefer not to have handrails but understand the health and safety requirement
Here are some of the key community influences:
We have only proposed handrails where necessary and have sought a design which compliments the landscape
At outline design, you proposed a timber boardwalk between the ship and high street and there are mixed views
The community need to be involved in the design choices
During detailed design we removed the timber boardwalk element from the design I am worried about access restrictions once the scheme is complete
We’d like to know if the existing structures and buildings can be used as part of the new flood and erosion defences
The scheme is designed to enhance accessibility. There will be changes to foreshore access in places but this is due to the need to improve the flood defences We value the heritage and landscape of Langstone so material choices really matter to us as residents
We have increased the community engagement schedule to allow for more feedback to be gathered
We did further structural investigations which confirmed the structures are not suitable and new structures are needed
At outline design, you proposed a flip up flood barrier for the Car Park at the Ship Inn, but this design is not suitable During detailed design we revisited this and have changed the design to land raising to minimise impact
We have sought advice from a heritage consultant and the HBC Conservation Officer, we will replace materials like for like or at an improved standard across the scheme listening to preferences
We enjoy visiting the two pubs but are worried we will lose the view across the harbour We have included an option to include a glass topped flood wall at the Ship Inn and Royal Oak, subject to funding
havant.gov.uk coastalpartners.org.uk
What Happens Next? 2023/24
2024
2024
2024
2024/25
2025
Winter
Spring
Summer
Autumn
Winter
Spring
Detailed Design
HBC Key Decision
Licencing & Consenting
HBC Key Decision
Procure Contractor
Construction Starts
Design The detailed design is 100% completed
Seek permission to apply for planning permission and other consents
Application for necessary licences and consents
Seek permission to undertake procurement for a skilled contractor to undertake the works
Procurement exercise to identify skilled contractor to undertake the works within budget
Preliminary works start with site set up, followed by the main coastal defence works over a 2-year period
We need your feedback...
Please take some time to fill out the
PRE - CONSTRUCTION ENGAGEMENT Do you support the design proposals which have been developed?
VISITOR SURVEY which is available during the exhibition and online
Do you have feedback that you’d like to provide?
after the event
FIND OUT MORE & STAY IN TOUCH Visit our PROJECT WEBPAGES
Sign up to the e-Newsletter
Look out for further ENGAGEMENT
Contact us at: Langstone-FCERM @havant.gov.uk
havant.gov.uk coastalpartners.org.uk
The Langstone Scheme Aims to: To construct new coastal defences with a 50-year design life with minimal maintenance and operation requirements.
Reduce the impact of flooding and erosion to the most vulnerable residents, businesses, the local economy and the A3023 at Langstone which is considered critical infrastructure.
Develop and deliver a Scheme that is affordable and represents best value for money, ensuring the optimal use of resources and delivering effiencies where appropriate.
The CORE Scheme
Develop and deliver a Scheme which is acceptable to Havant Borough Council, Statutory and non-Statutory Consultees, Wider Stakeholders, and Community.
Deliver Coastal Flood and Erosion defences that are sympathetic to the heritage and landscape of the area and achieve wider benefits such as place-making, regeneration and improved amenity.
1A. Footpath Raising
Enhance and improve the environment and provide a minimum of 10% biodiversity net gain through the scheme.
5. Earth Embankment 5. Reinforced Concrete Flood Wall
The CORE Scheme refers to the
5. Masonary Clad Sheet Pile Wall with Option for Glass Top
least cost scheme alignment L ang stone H igh Str e
which protects the largest number
4. Flood Gate at High Street
of properties. This includes 53 residential and 4 business properties which will be better protected through implementing this scheme.
4. Concrete Flood Wall with Suitable Cladding, New Brick Quay Footpath
1B. Embankment and Capital Refurbishment 2. Sheet Pile Wall
3. Reinforced Concrete Flood Wall at The Ship Inn 3. Reinforced Concrete Flood Wall at A3023, Car Park Surface Raising A3
A further 6 residential properties
0 23 idge
6. Rock Armour
r ne B gsto Lan
not currently at risk, but will become at risk by 2040 due to
et
climate change will also be better protected withing the lifetime of this scheme.
The ADDITIONAL Scheme
Frontages within the core scheme
There are two ADDITIONAL frontages including the Mill Lane frontage (1B) and Langstone Spit (6), that are not included in the Core scheme due to affordability.
will be proposed as part of the Planning Application, subject to securing the required funding.
At this stage it has not been possible to identify any viable investment in these frontages, however detailed designs have been prepared as we continue to investigate any potential opportunities as these become available.
havant.gov.uk coastalpartners.org.uk
Frontage 1A Hayling Billy Trail North Existing
Currently there are no flood defences along this frontage which is a footpath and National Cycle Route 2 cycleway forming part of the Hayling Billy Trail. Either side of the path is a narrow strip of Havant Borough Council land (which is vegetated) and there are residential properties.
EXISTING
Proposed
The leading design solution for this northern section of the Hayling Billy Trail is for a new 170m long flood defence which comprises of a raised earth embankment, following the line of the existing Billy Trail cycleway. The existing cycle path is to be upgraded to a new 3m wide cycle path which sits on top of the flood embankment. The path surface will be raised between 0m and 0.7m to meet the levels
PROPOSED
required and will be surfaced with asphalt. There will be some impact on the existing vegetation to enable the works to take place within a narrow area. These will be replaced with appropriate vegetation to retain the tree-lined corridor of this footpath and cycle route.
Design Considerations Image shows example cross section of 1A cycle/footpath raising and widening to 3m.
Proposed New Seating Along Hayling Billy Trail
UTILITIES There are several important services located within the design footprint.
CYCLE PATH This is the main cycleway. Hampshire Highways defined 3m width of path.
NARROW AREA The design is constrained on either side by private properties and utilities.
LANDSCAPE MATERIALS More trees will be planted to The footpath/ cycleway will replace those impacted by be surfaced with asphalt. construction.
havant.gov.uk coastalpartners.org.uk
Frontage 2 Hayling Billy Trail South Existing
Currently there are no formal flood defences along this frontage which is a footpath and National Cycle Route 2 cycleway forming part of the Hayling Billy Trail which connects to the A3023. Either side of the path is a narrow strip of Havant Borough Council land, which includes Vegetated Shingle on the beach, and saltmarsh and scrub further landward.
EXISTING
To the east side of the path there are residential properties and gardens. To the west side of the path there is a tidal creek which is sheltered by Langstone Spit and features intertidal habitats.
Proposed The design for Frontage 2
consists of a of a sheet-piled wall and localised realignment of the cycle/footpath.
We have worked with key stakeholders to propose this updated design which is the only solution that: • Avoids encroachment on sensitive intertidal habitats. • Avoids clashing with important utility services within the footprint of the design. • Enables greater flood protection to the residential properties without compromising their privacy. • Provides opportunities to enhance the environment, and deliver biodiversity net gain. • Enhance the cycleway provision through a wider path and reduced flood risk.
PROPOSED WITH NEW SEATING
Image left shows general arrangement with realignment of cycle/footpath, and other landscaping opportunities.
Design Considerations
Raised earth embankments are included where the defence alignment needs to cross existing utility pipes. The existing cycle path is to be upgraded to a new 3m wide cycle path which sits adjacent to the sheet-piled wall and will be surfaced with asphalt. Frontage 2 ties in with Frontages 1A and/or 1B and the existing higher levels on the A3023 road.
UTILITIES There are several important services located within the design footprint.
CYCLE PATH This is the main cycleway. Hampshire Highways defined 3m width of path.
NARROW AREA The design is constrained on either side by private properties, utilities and Langstone Harbour
INTERTIDAL HABITAT Minimise encroachment on protected habitat and enhance biodiversity.
MATERIALS The footpath will be surfaced with asphalt.
havant.gov.uk coastalpartners.org.uk
Frontage 3 Car Park at the Ship Inn Existing Frontage 3 starts at the A3023, crossing the car park at the Ship Inn to the Pub itself. The car park is popular with visitors and has two access slipways providing launch points into Chichester Harbour.
EXISTING
Proposed The updated design accounts for feedback on the usage of the car park and a review of operation and maintenance requirements. The final proposals form a continuous flood defence. There is a dwarf sheet piled concrete flood wall which ties in with the A3023, linking into localised surface raising to form a bund within the car park itself.
PROPOSED The slopes of the new bund are designed to optimise vehicular use of the space as a car park. The raised area will be surfaced with asphalt. This ties into the new Ship Inn flood wall, with new steps and access ramp enabling
access for visitors to the Ship Inn. We are working with stakeholders to investigate full resurfacing of the HCC owned car park at the Ship Inn, subject to securing additional funding. Image shows example cross section of A3023 dwarf flood wall.
Car Park at the Ship Inn
New ramp and steps with handrail to access the Ship Inn.
Design Considerations Image below shows example cross section of Car Park surface raising.
UTILITIES There are several important services located within the design footprint.
SLIPWAY ACCESS There will be no impact to existing slipway access.
CAR PARKING BUSINESS The design enables There will be new steps and continued use of the area as a ramp for accessing the a car park. Ship Inn.
MATERIALS The car park surface will remain as black asphalt as required by the landowner.
havant.gov.uk coastalpartners.org.uk
Frontage 3 The Ship Inn Existing
The Lookout
Frontage 3 continues to the Ship Inn and courtyard seating area, and the Annexe. There is no definitive footpath along this 52m stretch of coastline from the car park at the Ship Inn. Pedestrian access is along the foreshore or through the courtyard to meet the definitive footpath which starts at the Lookout. The existing flood defences have reduced structural integrity and require upgrade.
Old steps removed from this location
EXISTING
Proposed The latest proposals form a continuous flood defence. A new concrete flood wall is proposed, which will be clad with engineered red brick. The design accounts for the business use of the Ship Inn as a public house. The wall is designed to be able to incorporate a glass top, should funding be secured prior to construction. This will ensure no impact on the stunning harbour views. The section of concrete apron and white picket fence for the Annexe will be replaced with a new concrete flood wall, with accessible footpath and safety handrail replacing the existing apron. There will be new foreshore steps constructed in a more suitable location. This ties into Frontage 4 at the Lookout. Image shows example cross section of Ship Inn Wall with proposed glass top.
PROPOSED
New access steps added between footpath and foreshore.
Image shows example cross section of Ship Inn Annexe Wall.
Flood Glass Top
Design Considerations New SafetyHandrail
FOOTPATH ACCESS Design improvements include better, wider footpath surfaces and easier foreshore access.
HARBOUR VIEWS The proposals include a glass top flood wall to retain views from the Ship Inn.
NARROW AREA The design is constrained on either side by private properties and the foreshore.
ENVIRONMENT MATERIALS Design has minimised loss The new flood walls will be of intertidal habitat. clad in red brick to tie in with other frontages.
havant.gov.uk coastalpartners.org.uk
Frontage 4 Lookout to The Green Existing Frontage 4 extends between the Lookout and Langstone High Street. The Lookout frontage is currently characterised by a low wall and footpath, with an offset upper garden brick wall to the residential properties behind. Structural investigations considered whether these could be integrated into the scheme as flood defences however it was determined they were unsuitable and that new structures were required.
EXISTING
The footpath here varies in level and is often submerged by the tide. It is also very narrow in places with an unprotected edge.
Proposed The proposal is to construct a new concrete flood wall with heritage brick cladding against the existing upper wall. The lower quay wall will be rebuilt to the same level and clad with engineered brick. The footpath will be slightly wider where possible to improve access, whilst minimising loss of foreshore habitat as far as technically feasible.
PROPOSED
Handrails We have followed health and safety guidance which advises that a continuous handrail is installed where there is an unsafe drop and therefore a risk to the public.
Image shows example cross section of the Watchtower Wall and Footpath with handrail.
New Safety Handrail
Pedestrian Access Access to the Coastguard Cottages from the footpath will be maintained. There will be new flood boards prepared for the gateway which will be installed during a flood event (and stored in a suitable place when not in use). Flood boards are better than a gate in this location as the gateway is too narrow.
Design Considerations SAFETY BEACH ACCESS A new handrail is included We are exploring potential to improve the safety of the for beach access along this footpath which will continue frontage. to flood during high tides.
Access to the beach is now provided via the new access steps at the Ship Inn Annex, and we are exploring other opportunities for gated access at other locations along the handrails.
NARROW AREA The design is constrained on either side by private properties and the foreshore.
FOOTPATH ACCESS The Footpath is wider and will be surfaced with an exposed aggregate concrete finish.
Location of new Flood Boards
MATERIALS The cladding materials have been selected to replace like for like where appropriate.
havant.gov.uk coastalpartners.org.uk
Frontage 4 The Green Existing Frontage 4 extends between the Lookout and Langstone High Street. The Green Cottage section is currently characterised by a Grade II listed residential property. The existing structures are a mixture of low stone setback walls. The footpath here currently crosses The Green which sits on a brick quay wall. Structural investigations considered whether these could be integrated into the scheme as flood defences. Some upper elements were regarded as suitable for integration (with enhancement); however, the brick quay was not suitable meaning new structures were required.
EXISTING
Proposed The footpath will sit on top of a new concrete quay wall with set back concrete upper flood wall. The lower quay wall will be clad with engineered red brick. The upper wall will be clad with flint to tie in with neighbouring walls. We are working with the landowner to finalise any detailed requirements to tie in with the property walls.
PROPOSED
The seaward edge of the footpath will now be protected with a continuous handrail along Frontage 4. This section will propose the realignment of the footpath around The Green (green line on map) as the optimum solution which minimises need for pedestrian flood gates.
The Green
Image (right) shows example cross section of Green Cottage Wall with proposed footpath and handrail.
Direct consultations are being held with private landowners directly impacted and with Hampshire County Council. Following confirmation of the design, a Public Path Order application will be needed to permanently divert the footpath.
Design Considerations SAFETY A new handrail is included in the design to improve the safety of the footpath which will continue to flood during high tides.
PRIVATE PROPERTY Working with impacted landowners to establish access requirements and suitable finishes.
NARROW AREA The design is constrained on either side by private properties and the foreshore.
FOOTPATH ACCESS The Footpath is wider and will be surfaced with an exposed aggregate concrete finish.
New Safety Handrail
MATERIALS The cladding materials have been selected to replace like for like where appropriate.
havant.gov.uk coastalpartners.org.uk
Frontage 4 Flint walls Existing The Flint Walls section is between the Green and Langstone High Street, where the upper offset garden wall and building walls to the residential properties behind are flint faced (a mix of cobbles and knapped flint). Structural investigations considered whether these could be integrated into the scheme as flood defences however it was determined they were unsuitable and that new structures were required.
EXISTING
The footpath here is often submerged by the tide, very narrow in places with an unprotected edge.
Existing Narrow Footpath
Existing Flint Wall
Proposed The proposal is to construct a new concrete flood wall with flint cladding against the existing upper wall. At the Winklemarket there will be a breathable gap where the existing walls form building walls. We have worked with specialists to establish how the flint cladding can be built to look like the existing walls. The lower quay wall and footpath will be rebuilt and clad with engineered brick. The footpath will be slightly wider where possible, whilst minimising loss of foreshore habitat as far as technically feasible. The seaward edge will now be protected with a continuous handrail along Frontage 4.
PROPOSED
Image shows example cross section of Garden Flint clad Wall with proposed footpath and handrail.
New Safety Handrail
New Flint Cladding
Image shows example cross section of Winklemarket flint clad Wall with proposed footpath and handrail.
Design Considerations SAFETY PRIVATE PROPERTY A new handrail is included We have worked with in the design to improve the private property owners safety of the footpath which to adapt the design to will continue to flood during complement existing high tides. buildings and improve flood protection
NARROW AREA The design is constrained on either side by private properties and the foreshore.
FOOTPATH ACCESS The Footpath is wider and will be surfaced with an exposed aggregate concrete finish.
MATERIALS The cladding materials have been selected to replace like for like where appropriate.
havant.gov.uk coastalpartners.org.uk
Frontage 5 High Street Existing Frontage 5 extends between Langstone High Street, around the Royal Oak Pub and north along the footpath to the meadows. Currently, at the bottom of the High Street, there are no coastal defences. Therefore, during the highest spring tides and during storm events, water floods up the road here, occasionally as far as the A3023.
Proposed
EXISTING
The design solution for the end of Langstone High Street consists of a new vehicular flood gate across the high street to tie in with defences either side. Adjacent to the Winklemarket there will be a timber clad pedestrian flood gate. The slipway here will be improved. The double-leaf vehicle gate and single leaf pedestrian gates will be fixed open for the majority of time, and closed when the water level is high enough, typically alongside a flood alert or warning. Once a gate supplier has been agreed, we will finalise the look and feel of the design. There has been a preference shown that the gate will be timber clad.
PROPOSED
Visualisation of the proposed new flood gates in the fixed open position.
Stakeholder preference is for an Oak clad flood gate, which will mature into a grey colour over time.
Image shows example cross section of the high Street flood gate and slipway.
Two new bins proposed to replace existing ones.
Design Considerations UTILITIES FLOOD GATE POSITION ACCESS GATES There are several important Has been designed to Low tide foreshore vehicular The procedure for opening services located within the optimise defence height and access will continue for and closing gates will be design footprin. minimise defence length. residents while gates are set out in agreement with open. landowners.
MATERIALS Materials have been selected to complimentexisting and reduce visual impact.
havant.gov.uk coastalpartners.org.uk
Frontage 5 Royal Oak & Cottages Existing Leading around from the High Street is the Royal Oak and adjacent residential cottages. The structural integrity of the existing quay and building walls was investigated through structural investigations which highlighted these could not be integrated into the design and that new flood defences would be needed.
EXISTING
Proposed The leading solution is a new reinforced concrete flood wall cladded in a masonry stone mix, with a piled concrete apron buried beneath the foreshore. Some frontline residents and businesses expressed interest in the incorporation of a flood glass top to the defence.
PROPOSED
The design of the new flood wall is therefore adaptable for a glass top in front of residential properties and businesses, subject to New Flood Glass topped flood wall. securing additional funding, otherwise a full height flood wall will be constructed. The potential impact on landscape and heritage was explored with an independent Heritage Consultant and the Havant Borough Council Conservation Officer who also support the inclusion of glass in the design.
Image (left) shows example cross section of the Royal Oak Flood Wall (full height).
Image (right) shows example cross section of the Royal Oak Flood Wall option topped with Flood Glass.
Masonry cladding layout options.
Design Considerations
Masonry cladding samples.
UTILITIES PRESERVATION ACCESS There are several important A flood risk reduction Low tide foreshore vehicular services located within the scheme will help to preserve access will continue for design footprint. and extend the life of residents while gates are heritage features here. open.
BUSINESS A ‘dry’ area in front of the Royal Oak will mean pedestrian access at high tide.
MATERIALS Materials have been selected to compliment existing and reduce visual impact.
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Frontage 5 Allotment & 21 High Street Existing Frontage 5 continues around the Royal Oak & garden up along the footpath (108/54b/1) into the meadows north of Langstone High Street. This frontage features privately owned allotment and dwellings which require vehicular access.
Proposed We have been working with the relevant landowners to progress the final designs for this frontage, which is shown in the annotated image below. The constraints here are complex meaning a blend of defence types are proposed.
Royal Oak Pub Garden.
Privately Owned Allotment with private access gate.
Privately Owned Residence with private access gate.
There is a narrow footpath here which is often waterlogged.
EXISTING Langstone Cutters Rowing Club and others use the slipway here.
New Full height flood wall defence along Royal Oak garden frontage.
New set back flood wall along the privately owned Allotment.
New Private allotment Access Gate which will remain closed.
No impact on Rowing Club slipway access once works complete.
PROPOSED New Private Access Gate which will be closed during a flood event.
New Emergency Egress Steps.
Footpath to North remains open and accessible at all times.
New Pedestrian Gateway with flood boards (only closed during flood event).
Image shows example cross section of the Private Access Gate.
Image shows example cross section of the Royal Oak Flood Wall (full height) section.
UTILITIES There are several important services located within the design footprint.
Image shows example cross section of the Allotment flood wall.
GATES The procedure for opening and closing gates will be set out in agreement with landowners.
Design Considerations
NARROW AREA The design is constrained on either side by private properties and the foreshore.
EGRESS There are emergency egress steps built into the defence here and an alternative egress route along the footpath.
SLIPWAY ACCESS There will be no impact to existing slipway access and use of the boatyard following the works.
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Frontage 5 Footpath to the Meadow Existing The existing footpath (108/54b/1) takes walkers to the meadows north of Langstone High Street. The path is narrow in places and is subject to waterlogging from the adjacent stream.
Proposed Embankment Section An embankment section is proposed to tie in the new flood wall with higher levels in the meadows.
The existing gap in the hedgerow will closed by the embankment and new hedge top. A new access will be made in the hedgerow further west where the land is higher.
Existing Footpath
PROPOSED
Visualisation of new flood embankment in the meadows
NEW Embankment
Proposed Floodwall Section Extending north along the boundary of No.21 High Street, the proposal is for a new concrete L shaped flood wall with timber fence topper. The footpath will be retained and where possible widened. Through installing the flood defence, a new surface will be integrated in for the footpath. For the section of footpath (108/54b/1) we propose an improved surface which is ‘Bodpave 40’. This is a Porous paving system.
Proposed Footpath Surface
Footpath 108/54b/1 between High Street and Meadows.
Design Considerations REPTILES Habitat mitigation will be included within the meadows to account for any construction impact.
Private Residential Property
FOOTPATH ACCESS We are proposing an improved footpath surface and width.
Image (left) shows example cross section of the footpath flood wall with timber fence topper.
NARROW AREA The design is constrained on either side by private property.
LANDSCAPE More trees will be planted to replace those impacted by construction.
MEADOWS Suitable landscaping will be implemented to include native wildflower and hedgerow species.
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Additional Scheme
Further to the Core scheme, the detailed design has been prepared for the ‘Additional Scheme Frontages’ (F1B and 6). Due to the current rules in place which determine how much Flood Defence Grant in Aid (FDGiA) funding a project can be eligible for, we have not been able to make an affordable case to proceed to the next stage of licencing and consenting or to construction for the Additional Scheme, without securing further investment and private contributions.
Frontage 1B Mill Lane and Harbourside Private defences at Mill Lane and Harbourside At present, the existing structures are in need of works to improve their condition. The Additional scheme proposals are for a ‘Capital Refurbishment’ of the existing private defences, and an earth embankment to the West on the east bank of Langbrook Stream. This proposal would offer the greater standard of protection required, however the cost to deliver the scheme proposals is not likely to be affordable to the community without further investment.
Private Landowners have ultimate responsibility for protecting their own property from flooding and erosion but must act within statutory planning regulations and other applicable legislation. Close proximity to protected habitats limits the construction methods available which are likely to get consent. We have also investigated an alternative staged approach to improving the condition of these private defences in a more affordable way. We have worked closely with this community to explain the design requirements and have prepared detailed designs for a feasible solution, should funding and consents be secured in the future to undertake the works.
Private residential properties at Mill Lane and Harbourside
Intertidal Foreshore Habitats
PROPOSED
Langbrook Stream
Frontage 6
Existing eroding Langstone Spit
Langstone Spit The leading design solution for Langstone Spit remains unchanged from rock armouring for the 50m section at the end of the spit, proposed to reduce erosion of the end of the Spit, helping with stabilisation. Granite rock was specified given its higher density and therefore lower required rock-armour size which in turn reduces the amount of encroachment into the designated foreshore. This proposal will need further consideration in terms of whether it is likely to gain the necessary consents and will require environmental impact assessment. It has also been difficult to source funding for this frontage due to the weak cost:benefit score with current funding rules, however a detailed design for this frontage has been prepared.
Proposed Granite rock armouring
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The Future Landscape of Langstone A Community more resilient to Coastal Flooding and Erosion New Flood Defences Future maintenance of structures and the operation of flood gates will be necessary. Maintenance has been a key design consideration, with materials selected in liaison with asset owners, showing preference for readily available materials such as asphalt which will make repairs easier, and also materials which
Visualisation of proposed flood glass
are resilient to the marine environment.
Flood Gate Operation The proposals include for two vehicular access and four pedestrian flood gates, as well as two locations where flood boards are proposed. These will all require deployment prior to a flood event.
Visualisation of proposed flood gates
Coastal Partners manage the operation of a network of flood gates and other structures through a duty coastal incident officer (CIO) role (24/7). In the Havant Borough, Coastal Partners work with NorSE to operate emergency flood defences. Once we have a preferred gate supplier, an operational manual will be prepared in consultation with our Contractor, Langstone Flood Watch and individual landowners affected so that all parties understand roles and responsibilities. This will set out the trigger and procedure for closing the gates, alerting the community and emergency action planning.
Flood Gate Deployment in Action at Old Portsmouth, Dec 2021
The gates would be shut prior to an extreme high tide event (not every high tide event would require closure of the gates). Vehicular and pedestrian access will not be possible until the tide drops, and the gates are re-opened.
Residual Flood Risk
Property Insurance
This Flood and Coastal Erosion risk management scheme predominately focuses on reducing tidal flooding and erosion risk.
Coastal FCERM Schemes have the potential to reduce insurance premiums but this is not guaranteed. It can often take some time after scheme delivery for the Environment Agency to update their flood risk maps and areas benefiting from defences.
It proposes a sufficient drainage network to ensure any water landward of the defences continues to drain at low tide. There will be a remaining residual risk from surface water, spray overtopping, and significant events which exceed the standard of protection. Landowners will still need to manage their own risk through property level protection such as flood boards.
Coastal Partners work closely with the Environment Agency who are responsible for issuing any flood alerts. You can sign up to receive flood alerts from the Environment Agency by scanning the QR Code:
Examples of property level protection
Please scan the QR Code for further information on flood insurance:
The insurance industry then updates their own records. Its best to have a direct conversation with the insurance company you use.
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The Future Landscape of Langstone 2 Improved Access
Space for Cycles
Wider Footpaths
The Hayling Billy Trail
There are a network of footpaths across Langstone which are popular with the local community and visitors alike.
Visualisation of Footpath with Handrail Visualisation of 1A Hayling Billy Trail
The Equalities Act 2010 places the public sector under an Equalities Duty. In having regard to eliminate discrimination and advance equality we consider the need to provide accessibility and the use of the footpath has to be considered for all individuals. We are proposing improved access for people with less mobility, increasing minimum footpath width to 1.5m as per Department of Transport Mobility Guidance.
We will work with Hampshire County Council to share feedback from the community to inform how use of this access is managed, specifically about shared pedestrian and cyclist use of the Hayling Billy Line, to ensure pedestrians feel comfortable sharing this popular access route.
Space is constrained, so there is a balance between creating wider footpaths within the space available as not to encroach into designated habitats.
Improved Surfaces The condition of the surface of these footpaths is of interest from the community, with preference for surfaces which are easy to navigate, non-slip, not subject to waterlogging and in a good state of repair. Where the proposed design includes sections of footpath, it is proposed that the replacement surface is of improved condition than pre-existing, and easy to repair.
Bike Racks
Visualisation of F2 Hayling Billy Trail
Way
Sharing Information Improved Signage and Interpretation The proposals include for refreshed signage and interpretation boards. These will celebrate the features of Langstone’s built and natural environment, working with the community and key stakeholders. We will also focus on safety signage and wayfinding where appropriate.
Existing information boards at Langstone
The national cycle route which runs along the Hayling Billy Trail through Langstone will be upgraded as part of the Scheme along a 350m section. The route will be widened to 3m to meet Hampshire Highways development requirements. The surface will be of the highest standard, more resistant to wear and be easily repaired.
The proposals include for 4 new cycle racks located across the scheme.
Public Realm Design Material Choices We have worked together with the community and key stakeholders to establish the most appropriate materials, opting for like for like where possible. There are also a range of other improvements which can be delivered as part of this scheme such as new places to sit on Frontage 2 and appreciate the surroundings, planters with coastal vegetated shingle, and replacement litter bins at Langstone High Street.
New Benches
New Litter Bins
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The Future Landscape of Langstone 3 Wild Landscapes & Boosted Biodiversity Replanting Nature We have worked with experts to better understand the environmental features of the area and ensure the most appropriate species are selected to complete the landscaping aspect of the scheme. Areas cleared of vegetation will be replanted with a range of specially chosen native species. These include a mixture of grasses, trees, shrub and species rich meadow, tolerant to life at the coastline.
Biodiversity Net Gain
Coastal Wildflower Mix
Under the Environment Act 2021, from January 2024 it will be a legal requirement for developments that require planning permission to provide at least a 10% Biodiversity Net Gain as part of their scheme proposals. The scheme will therefore propose a landscape which is more visually and ecologically diverse than what was there previously, creating a better habitat for local wildlife.
Habitat Mitigation Hedgerow Seed Mix
Tree Canopy Existing Tree Survey
We have taken professional advice from an Arboriculturist Consultant to establish the impact on tree species across the scheme frontages as well as opportunities for replanting.
The Consultant has mapped out the existing tree canopy and surveyed and graded every tree within the scheme footprint. Where there is a clash between trees and the scheme proposals, a tree clearance plan has been prepared to identify: Trees unaffected and therefore retained; Trees to be retained with mitigation measures applied to reduce impact.Trees which would not survive the development and will require removal as part of enabling works. Vegetation clearance plans are available to view at the exhibition.
More Trees The project team understand the ecological value of tree canopies and have therefore specified in the design that for every tree impacted, at least 2 new trees are planted. Replanting Schedules and plans are available to view at the exhibition.
Native Species Not only are there more trees within the proposals, the species of tree have been selected from native species, including fruit trees which will blossom and provide a source of food for insects.
Langstone is home to sensitive environments which are nationally and internationally important for nature conservation. We have a responsibility to assess and seek to minimise the impacts of new development on these habitats and species and support their restoration and enhancement. We are proposing an array of features which will mitigate impact on important species such as reptiles, insects and bats, and support their improvement.
Intertidal Habitats Co-Creating Ecological Niches We are exploring opportunities to develop a community-led project for creating bespoke intertidal habitats. This project will look to involve the community and combine creativity with environmental enhancement. More detail to follow in 2024.
Saltmarsh Restoration In association with the scheme, we are investigating the feasibility of restoring Langstone’s precious saltmarsh habitats, which were historically more extensive within the harbours. We have secured additional funding to explore these opportunities further.
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The Scheme Benefits & Costs
£28.6M
The Scheme Benefits The main benefit of the scheme is the increased coastal flood and erosion resilience of the community at Langstone and Hayling Island.
TOTAL BENEFITS
The scheme will reduce the risk of flooding to the area and will also reduce the risk of structural collapse of the existing quay walls over a 50-year period.
Appraised at Outline Design (2021) using HM Treasury guidance
Both residential and non-residential property damages have been assessed alongside a range of intangible damages to estimate the economic benefits of the scheme.
Direct damages to property
Community Flood Impact
Indirect Impact on Transport
Business Impacts
Ecosystem Services
Health and Wellbeing
£8,535K damage to residential and commercial properties £398K damage to vehicles.
£2,287K damage associated with risk to life £567K damages for emergency clean up and temporary accommodation.
£1,665K traffic disruption damages and public infrastructure damages (road damages) £5,125K damages due to disruption to commuters from Hayling Island.
£232K business disruption loss to the public houses over the next 10 years (local economy impact). An eight-week clean up period after a flood event expected to lead to an additional loss of approximately £200K business turnover due to closure.
Do Nothing scenario would have adverse impact on Ecosystem Services; negatively impacting climate regulation, hazard regulation, pollination, tourism and recreation, culture, science and education, aesthetic values and wild species diversity.
Loss of the public footpath between Ship Inn and Royal Oak has potential to decrease physical activity levels of the population £320K damages Mental Health Impacts £1.35M. Visitors lost to other destinations £178K per year.
Core Scheme Costs At the 100% design stage, we received new estimates of whole life cost from our cost consultant Faithful and Gould, who were supported by Early Contractor Involvement from Mackley. These estimates have helped us to generate a target Core Scheme cost of £17.98 These whole life costs are inclusive of: • Design, Survey and Management Fees • Construction Costs • Maintenance Costs • Licencing and Consenting Fees • Other Authority Fees such as Utilities • Contractor’s Construction, Client Design & Development Risks and Optimism Bias (£2.5M) • Community Engagement This does not include the costs for the Additional Scheme.
£17.98M Core Scheme Cost Estimations prepared by Cost Consultants Faithful and Gould (now Atkins Realis) January 2024
Why have costs increased? We have generated cost estimates at key stages throughout the design process. At detailed design, we have commissioned a cost consultant to help define realistic and detailed costs. Some elements have increased in cost, whilst others have decreased through the detailed design. Reasons for the cost increases reflect a better understanding of global and local financial elements such as: • Price inflation. • Planning requirements. • Fuel and Energy cost increase. • Labour shortages. • Physical site constraints. • High quality materials and finishes. • Extended construction programme (from 1 year continuous programme to 2 year phased), start delayed by 1 year.
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Funding Secured
TOTAL FUNDING ALLOCATED
Government Funding
as of January 2024
The Government has put in place a mechanism for funding flood and coastal erosion risk management schemes called Partnership Funding. The principles are quite simple, the project costs are weighed up against the benefits and the number of properties that a Scheme protects. Schemes providing higher benefits and protecting more properties relative to costs are eligible for more Flood Defence Grant in Aid (FDGiA). Where projects do not qualify for full government funding, external funding contributions can be sought to make up the shortfall.
Partnership Funding The Langstone Scheme does not achieve a high Cost–Benefit ratio due to the relatively high cost of protecting a relatively small number of properties. We are therefore only eligible for £1.139M FDGiA towards the core scheme. We have therefore been proactive throughout the duration of design in sourcing and securing other sources of local partnership funding towards the Core Scheme costs: Havant Borough Council Community Infrastructure Levy [£2,625,000] Southern Regional Flood and Coastal Committee (SRFCC) Local Levy [£1,095,000] Other Government Department Funding [£2,344,629] Frequently Flooded Community Allowance [£2,500,000] Environment Agency Covid Recovery Claim [£101,549] Hampshire County Council [£250,000] Environment Agency Inflation Uplift [£818,000] Other Government Department Funding [£1,900,000] We have also allocated funding towards environmental improvements to be delivered as part of the scheme: WEIF Funding [£28,000]
£12.8M
National FDGiA
£1.14M
ALLOCATED Local Partnership Funding Sources
£11.6M ALLOCATED
As of January 2024
Environmental Statutory Allowance [£80,000]
Other Sources We also continue to investigate other sources of funding, including frequently updating existing funding applications to top up the funding allocated. We are currently bidding for: • HBC CIL Capital Bid [£5,200,000] • Environment Statutory Allowance [£340,763] • Endangered Landscapes Programme [£86,000]
Bidding
£5.6M
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Investing in Your Scheme The Funding Gap We have succeeded in securing a significant proportion of funding towards the core scheme costs, however there is still a gap to close between the scheme costs and the amount of funding allocated. There is a role for everyone in reducing the funding gap. The project team will continue to: • Seek efficiencies. • Seek additional funding and secure remaining bids. • Explore material options and seek compromise where there are excessive costs. • Reduce risks. • Seek other contributions.
£5.2M
Funding Gap as of January 2024
Interested in Contributing? Community Contributions Welcome We always try to do more to maximise value for money and seek contributions for our projects. It is legally permissible for stakeholders to enter into an agreement to make a financial contribution towards the costs of constructing a Scheme. We are obtaining legal advice as to how financial contributions can be secured. Your financial contributions could help us to close the funding gap for the core Scheme and help us to secure: • New coastal flood and erosion defences for the community at Langstone and Langstone Road. • Improvements to footpath and cycleway access through widening and better surfaces. • Solutions which maintain spectacular views across the Harbours. • Higher quality finishes which use materials requested by the community (such as flood glass) which will make this proposal unique to Langstone. • Ecological, heritage and amenity enhancements. • Finishing touches such as new seating, information boards and other public realm features.
We will be sharing more detail about investing in the Scheme in 2024
There are also other ways that the community can contribute in a non-financial way towards the Scheme as a whole: • Supporting the work by advertising and promoting its cause. • Offering access through private land or site set up arrangements. • Suggesting other ways to demonstrate savings. • Providing venues at reduced or no cost to support the engagement events.
Exhibition Survey Do you support the design proposals which have been developed? Do you have feedback that you’d like to provide? Don’t forget to fill out the Visitor Survey which is available as a paper copy at the Exhibition and as a digital version using the QR code
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