Project Overview

The Swanage Town Coastal Protection Scheme aims to provide a permanent flood defence scheme to Shore Road and the Mowlem Slipway area, The Square, The Parade and Lower High Street. This central location currently relies on emergency temporary de-mountable flood defences which are deployed in the winter by the Environment Agency to protect from high tides and storms.

Dorset Council are leading the progression of a single scheme to protect and mitigate tidal flood risk and in addition, help provide public realm improvements. An outline business case is being developed and will be submitted to the Environment Agency to bid for government funding for the scheme.

A number of proposals have been assessed against key feasibility criteria including; technical, financial, accessibility, maintenance, active/ passive design, heritage and potential for public realm improvements.

March 2018 flood event Photo credit: Malcolm Turnbull

 This has resulted in an outline proposal which we plan to use to support the business case and bid for funding. If successful, we plan to hold a wider public consultation to move this outline design to a detailed design.

Why are flood defences needed in Swanage?

In storm events or high tide and easterly winds, the current sea wall in Swanage suffers from overtopping. Overtopping is where waves are driven over the wall causing problems for both town centre businesses and the local community. This is an ongoing issue and has diverse implications for Swanage, impacting upon the environment, businesses and tourism. The impacts of these events on Swanage have demonstrated the need for improved protection. Overtopping is part of the picture, but Swanage is also at risk of flooding from rising sea levels. Our scheme will seek to reduce risk of flooding from both overtopping and rising sea levels.

Storm Ciaran November 2023 moved the temporary wave barriers which weigh 2.5 ton each! Photo credit: Andy Knill

 

Currently, the Environment Agency install seasonal temporary defences to protect the town during the winter months, but flood events are not just restricted to the winter season. With increasingly frequent storms events and rising sea levels, Coastal Engineers are currently working towards the provision of permanent flood defences for Swanage.

The Environment Agency installing the temporary wave barriers during Storm Babet October 2023 Photo credit: Anthony Leathem

 

The engineering design solutions are informed through baseline hydraulic modelling being undertaken on behalf of the project by JBA Consulting . The baseline model represents the current built and natural environment - you must create hydraulic models for the current 'defended/baseline' and 'undefended' scenarios (as applicable). JBA Consulting have completed their initial data review phase with baseline hydraulic modelling having started in mid-November 2022. Following initial model results provided in March 2023, the Project Team have requested a further set of modelling during winter 2023/24 to ensure optimal results to inform design options.

The team from JBA Consulting on site in Swanage Photo credit: Sara Parker

 

Public engagement feedback is informing specific modelling - this will provide opportunities for this information to be shared with the community in a tailored format in 2024. Previous public consultation results are supporting the outline business case to submit to the Environment Agency for funding to deliver a flood defence scheme. If funding is obtained, there will be further consultation with the wider community and specific groups as the scheme is developed.