Coastal management

The management of coastal flooding and erosion fits into a three-tiered framework comprising of:

1. Shoreline Management Plans, which suggest in broad terms how the coast should be sustainably managed in the future.
2. Coastal Defence Strategies, the production of which may be recommended by a shoreline management plan. Strategies cover shorter lengths of coast in more detail, often where there are more complex coastal management issues.
3. Coastal Defence Schemes, which are individual coast protection projects or construction works that are developed at specific locations.

• Shoreline Management Plans (SMPs)
• Coastal Defence Strategies (CDSs)
• Coastal Defence Schemes
• Coastal Partners
• South Down's SMP - Beachy Head to Selsey Bill

Shoreline Management Plans (SMPs)

Shoreline Management Plans (SMPs) set out how the coast should be best managed over the next 100 years. They identify the most sustainable approaches to managing coastal erosion and flooding risks in the short, medium and long term (0-20, 20-50 and 50-100 years respectively) over wide stretches of coastline.

The objectives of an SMP are:

• To define the coastal flooding and erosion risks to people and the developed, historic and natural environments.
• To identify the preferred policies for managing those risks.
• To identify the consequences of implementing the preferred policies.
• To set out procedures for monitoring the effectiveness of the policies.
• To inform others so future land use and coastal zone development can take account of the risks, the time frame of the risks and the policies.
• To comply with environmental legislation and social obligations.

SMPs are developed by coastal groups, who involve and consult interested authorities, businesses and the public frequently during the decision making process. An SMP divides the coastline into 'policy units', which are small stretches of coastline that have similar characteristics (in terms of risks or coastal processes). Within each unit, one of the below policy options is selected to achieve the above objectives:

• Hold The Line: Maintain or upgrade the level of protection provided by existing coastal defences.
• Advance The Line: Build new defences seaward of the existing defence line.
• Managed Realignment: Allowing the shoreline to move backwards or forwards, with management to control or limit movement.
• No Active Intervention: A decision not to invest in providing or maintaining any defences.
• Adaptive Management: Managing complex coastal areas by monitoring changes and acting on them in a planned but flexible way, increasing our understanding over time (unique to our area).

The council's coastline is covered by two SMPs; The North Solent SMP and the South Downs SMP. They join together at Selsey Bill.

Map of Shoreline Management Plan coverage (PDF, 831 KB)

Coastal Defence Strategies (CDSs)

Coastal Defence Strategies (CDSs) define how to deliver the policy set by Shoreline Management Plans (SMPs), along smaller sections of coastline. The key objective of a CDS is to examine coastal processes in detail, confirm or re-assess the SMP policy options and identify appropriate coastal defence schemes that meet economic, environmental and social criteria. The CDS will identify the preferred approach to coastal risk management and propose the best type of engineering scheme to manage risks, taking account of economic and environmental issues and any compensatory habitat requirements.

CDSs are usually prepared by all operating authorities along a defined coastal frontage, working in partnership. Similar to SMPs, once written, CDSs undergo wide public and stakeholder consultation before any final management decisions are made. The CDSs focus on policy units in much more detail than the SMP did. Each frontage has been assessed for flood and erosion risk management options, using government technical, economic, social and environmental criteria. The management options that may be selected for a policy unit are:

• No Active Management: Let nature take its course - no work will be carried out to maintain or repair defences, allowing them to deteriorate over time.

Active Intervention to hold the line: This policy option has various sub-options:

• Maintain: Defences are maintained at their current levels, but as sea levels rise flood risk increases over time.
• Sustain: Defences are raised and strengthened as sea levels rise keeping the level of flood risk the same as it is now.
• Improve: Defences are improved to increase the standard of protection over time, beyond the requirements of rising sea levels.
• Managed Realignment: Improve coastal stability by moving coastal defences to a more sustainable location further inland, allowing controlled flooding to occur.
• Adaptive Management: Managing complex coastal areas by monitoring changes and acting on them in a planned but flexible way, increasing our understanding over time.

The council's coastline is currently covered by two coastal defence strategies and one proposed coastal defence strategy, as illustrated by the map of Coastal Defence Strategy Coverage'

Map of Coastal Defence Strategy coverage (PDF, 779 KB)

The Pagham to East Head Coastal Defence Strategy has been fully completed and adopted by the council. The Environment Agency, Chichester and Arun District Councils worked in partnership to produce the Pagham to East Head Draft Coastal Defence Strategy. This document summarises our draft strategy findings and recommendations.

Pagham to East Head coastal defence strategy (PDF, 1 MB)

Flooding and erosion are real risks for people living on the coastline between Pagham and East Head. If there were no sea defences today, more than 300 houses and businesses in low lying areas could flood each year. With rising sea levels, this number could rise to more than 2,200 in the next 100 years. If the existing defences are not maintained, erosion could cause almost 1,500 properties to be lost to the sea. Subject to funding being available, our recommendations can manage the risk of flooding and erosion to communities and the environment over the next century.

Our work makes clear that securing funding for building and maintaining defences are serious and pressing issues for this area. The amount of funding available from central government to provide defences is limited. There is strong competition for these funds from elsewhere around the country. If funding cannot be found, plans will be needed to help people adapt to the inevitable changes.

Our coastline between East Head and Emsworth (Chichester Harbour) is not currently covered by a coastal defence strategy, however we are in the early stages of promoting the production of one.

Coastal Defence Schemes

Coastal defence schemes deliver shoreline management plan and coastal defence strategy policies on the ground, to manage flood and erosion risks. Coastal defence schemes tend to be capital projects that provide improved levels of protection against flooding and/or erosion and are much more significant than the routine on-going maintenance of the coastal defences that we also undertake.

When designing a scheme, studies may be undertaken to define the benefits for each management policy unit, and to precisely identify how any necessary engineering works or beach management will be undertaken. A business case (BC) will be written, which includes the preferred technical solution and is used to inform an application for funding from DEFRA.

The business case will include:

• Problem definition and objectives.
• Options for managing flood risk.
• Options appraisal and comparison.
• Selection and details of the preferred option.
• Implementation plan.

Once complete, the BC will be presented to the Environment in an attempt to secure national grant-in-aid funding towards each capital coastal defence scheme. The Environment Agency will critically review the BC and may approve it for funding, if it meets the appropriate criteria and there is sufficient economic justification.

Funding for coastal defence schemes is limited nationally, and construction works may only be completed where funding is secured. For much of our coastline, the cost to benefit ratio for coastal protection schemes is low, making it very difficult to secure national funding. Historically, funding for schemes comprised 100% national grant-in-aid funding where a clear business case could be made, however the policy on funding has changed and there is now an opportunity for community contributions towards schemes where 100% national funding cannot be justified/secured.

Various coastal protection schemes have been undertaken along the Pagham to East Head coastline over the last few years. These include:

• 2009 to 2011: Selsey West Beach Sea Wall Repair & Beach Recharge.
• 2015: Timber Breastwork Construction, Solent Way, Selsey.
• 2009, 2015 & 2022: Adaptive Management/Beach Recycling at East Head.
• 2011 to 2021: Beach Management, Selsey, Bracklesham & East Wittering.

Schemes we are currently working on and will be promoting over the next 5 years include:

• Selsey, Bracklesham & East Wittering Beach Management 2021 to 2026.
• Selsey Coastal Defence & Flood Scheme
• Adaptive Management at East Head

Coastal Partners

Flood and erosion risk management along Chichester District's coastline sits with Coastal Partners. Coastal Partners are a team of engineers, surveyors, project managers, environmentalists, and researchers.

Coastal Partners is the team responsible for managing coastal flood and erosion risk across five Local Authorities, the partnership includes Chichester District Council, Fareham Borough Council, Gosport Borough Council, Portsmouth City Council and Havant Borough Council. 

The Partnership was created under the recognition that the impacts of coastal flooding and erosion are not limited to the administrative boundaries.

Coastal Partners vision is to manage coastlines, improve community resilience and enhance the natural environment, and has been identified as an example of best practice by the Environment Agency and Defra.

To find out more, visit the Coastal Partners website (opens new window) or sign up to Costal Partners' Newsletter (opens new window) about projects along the coastline of Chichester.

South Down's SMP - Beachy Head to Selsey Bill

This SMP covers the open coast and harbour inlets between Selsey Bill and Pagham Harbour, for which this council is 'coast protection authority'. It also extends beyond this to Hurst Spit as the eastern limit of the SMP. The coastline to the east of Pagham falls under the jurisdiction of other coast protection authorities and this Council carries out no coast protection works beyond this point.

Final management policy options

Key to table:

• HTL: Hold The Line - shoreline management policy to maintain or upgrade the level of protection provided by existing coastal defences.
• MR: Managed Realignment - shoreline management policy to allow the shoreline to move backwards or forwards, with management to control or limit movement.

South Down's Shoreline Management Plan Summary Document (PDF, 6 MB)

Map of South Down's SMP Coastal Management Policy Units within the Chichester District (PDF, 819 KB)

North Solent SMP - Selsey Bill to Hurst Spit

This SMP covers the open coast and harbour inlets between Selsey Bill and Emsworth, for which this council is 'coast protection authority'. It also extends beyond this to Hurst Spit as the western limit of the SMP. The coastline to the west of Emsworth falls under the jurisdiction of other coast protection authorities and this council carries out no coast protection works beyond this point.

Key to table:

• HTL: Hold The Line - shoreline management policy to maintain or upgrade the level of protection provided by existing coastal defences.
• MR: Managed Realignment - shoreline management policy to allow the shoreline to move backwards or forwards, with management to control or limit movement.
• AM: Adaptive Management - shoreline management policy to monitor changes in complex coastal areas and acting on them in a planned but flexible way, increasing our understanding over time.
• NPFA: No Public Funding Available - this highlights that no public money will be available to fund the preferred management policy. This often relates to privately owned and maintained defences.

North Solent Shoreline Management Plan Summary Document (PDF, 2 MB)

Map of North Solent SMP Coastal Management Policy Units within the Chichester District (PDF, 845 KB)