Flood modelling uses predicted river flows, rainfall, and coastal levels combined with topographic data and flow equations to generate flood risk information (such as depth, velocity, flood levels, and hazards). Our team of specialists updated the coastal flood modelling for Shanklin to ensure it uses the latest information and software available.

The main coastal threat to Shanklin is erosion of the sea defences due to their current poor condition. Our latest modelling predicts that failure of the coastal defences would lead to the loss of the beach amenity and access to the esplanade. This which would have significant knock-on impacts to the area. We estimate that 76 residential and 55 non-residential properties are at risk of flooding from failure of the sea wall. The below map shows the anticipated flood extent in the event of defences failing.

Preventing this scenario can be achieved through either Option 3, Option 4 or Option 5*. Increasing the height of the coastal defences does not provide any additional erosion protection over Option 3, it only provides a greater level of protection against flooding associated with waves overtopping the sea wall.

Modelling results tell us that the risk of flooding from wave overtopping is low given the existing height of the defences and raised floor levels of properties. Modelling suggests that 5 non-residential properties and 0 residential properties in Shanklin would remain at risk of internal flooding from overtopping after completion of Option 3.

*Option 3 - Keep the existing defence level
*Option 4 - Raise the level of the defence in stages into the future
*Option 5 - Raise the defence level now

We received 42 responses in total. Of the 42 responses, 36 people gave their permission for us to publish their response.

Summary of key findings from the consultation responses:

• No one favoured the do nothing or do minimal option (short list Option 1 and Option 2). Respondents told us that better protection from coastal erosion and flooding is a priority.
• Option 5 was the most favourable option to raise the defences now to address future sea level rise. A total of 33 of the 36 respondents agreed or strongly agreed with taking option 5 forward. Respondents told us that there is an interest locally in raising the height of the coastal defences to reduce the risk to Shanklin from rising sea level both now and in the future.

The full report summarising the responses to the public consultation can be viewed here.

The Environment Agency and Isle of Wight Council are working together to manage coastal erosion and flood risk from the sea. Climate change is bringing more frequent and severe floods and storm events. The coastal defences in Shanklin include the sea wall and groynes. The beach also provides an important role by protecting the coastline behind it. The sea wall and groynes are in a poor condition and are reaching the end of their useful life. Without intervention the risk and severity of flooding and coastal erosion will continue to increase.

We have been looking at what we can do to manage coastal erosion and flood risk from the sea in Shanklin. We’ve narrowed down a number of options down to a short list of 5. Come and find out more about the options at one of our public exhibition drop-in events. Your feedback will help us to determine a preferred option.

They need further investigation to decide which, if any, we should take forward. We want to carry out a more detailed consultation, to hear your views on the options we have been investigating and your feedback will help us to determine a preferred option . We would also like your general feedback to help make sure we have considered all possible options before developing a design. The proposals will not eliminate the risk of coastal erosion and flooding, only lessen it. Our online consultation is running from Monday 23 October 2023 to Friday 1 December 2023.

The short list of options being considered:

Option 1: Do Nothing

Option 2: Do Minimum

Option 3: Keep the existing defence level

Option 4: Raise the level of the defence in stages into the future

Option 5: Raise the defence level now

We produced the following information for our public exhibitions to help explain what the scheme is about, what we have been doing so far and how we arrived at our short list of options:

• Introduction
• Scheme Extent
• Survey and Investigations
• Constraints and Opportunities
• Measures considered
• Project objectives and criteria
• Short list

You should review these documents before completing the consultation.

If you require these documents in a different format please don't hesitate to contact us: IOW_FDschemes@environment-agency.gov.uk

It is not a statutory requirement to consult on options for a coastal defence scheme. We would however like to understand the views and opinions of the end user, and recognise that this is good practice. The Environment Agency are running this consultation, and will do so in accordance with the guidance set out in the Government's Consultation Principles

If you have any queries or complaints about the way this consultation has been carried out, please email consultation.enquiries@environment-agency.gov.uk

Why your views matter

From a survey we ran over the summer of 2022, you told us that it is a local priority to reduce flood and coastal erosion risk both now and in the future in Shanklin. We encourage you to submit your response to the consultation online, which will enable us to manage your comments more effectively. It will also help us to gather and summarise responses quickly, accurately and cost effectively. However, paper copies can be requested or are available at Shanklin Library.

We, the Environment Agency, will keep your details until the scheme is complete. We will publish a summary of responses on Citizen Space within 12 weeks of this consultation closing. We will not publish any personal data. We will not respond individually to responses. In line with the Freedom of Information Act 2000, we may be required to publish your response to this consultation, but will not include any personal information. If you have requested your response to be kept confidential, we may still be required to provide a summary of it. For more information see our Personal Information Charter(External link). We are running this consultation in accordance with the guidance set out in the government's consultation principles.

If you have any questions or complaints about the way this consultation has been carried out, please contact consultation.enquiries@environment-agency.gov.uk

Public Exhibitions November 2023

We had a great turnout at our public exhibitions to showcase the short list of options for refurbishing the coastal defences. We were delighted to host nearly 100 visitors at The Clifton Hotel in Shanklin. Everyone who attended welcomed the opportunity to escape the wet weather, have a warm drink, and chat to the project team and other visitors to the exhibition. We also enjoyed Dinosaur Isle’s Blast from the Past event, where over 650 visitors passed through the doors. We want to thank everyone who took the time to come along.

Public Realm Questionnaire - Summer 2022

Our public realm questionnaire ran from 16th May 2022 to 31st July 2022, seeking views on how people interact with Shanklin Esplanade, what is most valued about it, and the perceptions amongst stakeholders of flood and coastal erosion risks both now and in the future. This will help to inform how we engage with stakeholders going forward, and capture any concerns, ideas and opportunities in the shortlist of options that we present to the public in Summer 2023.

A copy of the response summary report can be found here if you would like to find out more about the responses received and our response to them.

How do people use the public frontage at Shanklin?

What public realm improvements do people most want to see

Individuals who wish to follow up their responses, or points made within this document, in more detail are welcome to contact us at IOWFD_schemes@environment-agency.gov.uk.

To support the option development process, we need to collect data to better understand the current risk from coastal flooding and erosion from the sea. This is called the 'Surveying and Investigations' phase of the project. This will help us to make decisions about how best to manage the risk now and in the future.

Ground Level and Ground Penetrating Radar (GPR) Surveys - June 2022

Our contractors will be completing survey work using GPS equipment to obtain accurate land level measurements. They'll also be using ground penetrating radar to survey beneath the surface of the existing sea wall.

Ground investigation work - January 2023

Ground investigation work starts on 23rd January 2023 to help us assess the possible options for sea wall and groyne refurbishment. Specialist equipment will be used to drill boreholes through the sea wall and retrieve concrete cores which are sent to the laboratory for analysis. Machine excavated trenches located at intervals along the sea wall and next to the groynes will also be required. The results from the investigations will increase our understanding of the ground conditions and underground structures, including the foundations of the existing sea defences. Further details can be found here

Findings of the ground investigative work

• A total of four concrete cores were extracted at strategic locations along the concrete sea wall. Ferruginous Sands Formation (weathered bedrock) was encountered in all boreholes. This comprised a mixture of granular and cohesive soils described to range between very dense silty sand and firm sandy clay.
• The sea walls are much thinner than modern engineering standards. This tells us that works to the foundations will be needed as part of the refurbishment work.
• Borehole cores extracted from the ground have been donated to the British Geological Society. Their data sets provided useful information for our projects, and we hope our contribution will help others in the future.

The below image shows one of the borehole cores extracted from the ground and stored in its wooden container:

Coastal processes assessment

We completed a coastal processes assessment to get an understanding of the sediment movement across the beach.

• The historic trends in beach profile from 2004 to 2020 were reviewed. The min/max envelope in the above image shows the beach level overall remains relatively stable across the survey period.
• Short term fluctuations are observed and indicate seasonal changes.
• The overall stable condition is attributed to the constant nourishment of sediment received from the south-north net sediment transport rate of 25,000m3/year on average. The assessment shows that the two concrete groynes known as Osbourne and Hope Groynes are important for the long-term stability of beach levels.
• Past storm events have caused beach levels to lower by up to 1metre in front of the sea walls.
• One of the major physical impacts of a rise in sea level includes erosion of beaches. Our coastal processes assessment shows that beach levels are expected to lower by less than 5cm by 2040 and up to 2m by 2125. It is expected that the toe of the sea wall will have sufficient beach cover to protect it from erosion for the next 50 years. After this point, works to prevent scour at the toe of the sea wall may be needed.