Presentation on theme: ". Shoebury Common Flood Risk Management Scheme What is this exhibition for? This exhibition explains the various options considered for improving protection."— Presentation transcript:
. Shoebury Common Flood Risk Management Scheme What is this exhibition for? This exhibition explains the various options considered for improving protection against coastal flooding at Shoebury Common. Why do we need the project? The existing sea defences are lower than elsewhere in the borough, presenting a higher risk of coastal flooding. This risk will increase in the future as sea levels rise in response to global climate change. By undertaking works to this frontage, we can improve the existing protection to over 200 homes plus commercial properties now, increasing to over 500 properties as sea levels rise in the future. These properties would otherwise be at risk from more frequent coastal flooding as sea levels rise in the future. Where will the works be required? Taking into consideration technical, environmental and economic aspects we have identified that the defences need to be enhanced along the frontage approximately between Marcus Avenue and Ness Road. The location of this low section is shown on the map below.
Shoebury Common Flood Risk Management Scheme Flood and Coastal Erosion Risk The Shoebury Common frontage forms part of the line of coastal defence that protects the flood risk area of Shoeburyness. The map below shows the area at risk of coastal flooding from an event with an Annual Exceedance Probability (AEP) of 0.5% (i.e. Chance of occurrence in any given year is 1 in 200), with 50 years of sea level rise. In addition to the coastal flood risk, the land adjacent to the coast is at risk of erosion. This erosion pressure will also increase as sea levels rise. The area at risk from coastal flooding is urban, consisting of residential housing, commercial properties and open park land. The land closest to the coast is used for amenity, including visitor car parking, beach huts, walking, cycling and other recreational activities. The coastal road is also at risk from flooding and (in time) erosion.
Shoebury Common Flood Risk Management Scheme Option Development In undertaking our option appraisal process, we have investigated the feasibility of a range of options to improve the current and future protection against coastal flooding. In general terms, the options that we have considered fall into the following categories: Set back defence along the length of the frontage: This involves construction of a new defence (within the Shoebury Common area) set back from the existing seawall. The existing coastal defences, including the seawall, will be maintained in their present form. Further set back defence along road: This involves a combination of road raising, flood walls and embankments to join up the existing areas of higher ground landward of Thorpe Esplanade / Shoebury Common Road. This new set back line of defence would need to join up to the existing front line coastal defences to create a continuous line of defence for Shoebury and, therefore, the defence needs to cross the coastal road. Improve the existing defences: This typically involves raising the existing defences in order to protect against rising sea levels and reduce the wave overtopping that leads to coastal flooding. However, this is dependant on the type and condition of the existing seawall and is likely to require a substantial amount of beach recharge (importation of beach material) to support and protect the existing seawall. Replace the existing defences: This involves replacing the existing defences with a higher like-for-like or equivalent structure in order to protect against rising sea levels and reduce the wave overtopping that leads to coastal flooding.
Shoebury Common Flood Risk Management Scheme Options Considered Option 1: Landscaped floodwall through Shoebury Common and raising of existing seawall west of the Common Option 2: Floodwall along Lodwick, Ness Road and Waterford Road with high flood gate across road Option 3: Floodwall along Lodwick, Ness Road and Waterford Road with raised road and low flood gate Option 4: Raise existing seawall and promenade with beach recharge Option 5: New seawall and raise promenade
Shoebury Common Flood Risk Management Scheme Option 4 West of Common – Raise existing seawall to 5.8mAOD (by approx. 0.7m max) with a new brick wall facade and install flood gates at the various beach access points. In front of Common – Raise existing seawall to 5.8mAOD (by approx. 0.8m), and raise the level of both the promenade and beach huts behind the seawall with a landscaped embankment tying the elevated promenade back into the common. This option will also require the beach levels to be significantly increased (and maintained) in order to support the newly raised seawall and promenade. Cost ItemValue Initial Construction£6.0m Beach Recharge£1.8m* Pros: Sea views from promenade and beach huts remain unaffected Improved flood protection to beach huts, Uncle Tom’s Cabin, public toilets and car park Enhanced beach levels and larger promenade will improve the beach’s amenity use Beach huts and promenade remain visible from the road Beach access will be modified Cons: Cost prohibitive beach recharge (both initially and in future to maintain levels) is required to support additional wall loading (note that future funding for repeated beach recharge activities will not be guaranteed) Importation of beach material within an internationally and nationally designated site of nature conservation Disruptive to local services/utilities during construction 169 beach huts will have to be temporarily moved and stored (significant risk of damage) New embankment will change the landscape of the common Existing wall and revetment will require substantial repair before they can be raised (may prove to be cost prohibitive) Sea views from both Leitrim Avenue and Lodwick will be detrimentally affected *Assumes mobilisation fees for beach recharge are shared with other frontages
Shoebury Common Flood Risk Management Scheme Option 5 West of Common – Raise existing seawall to 5.8mAOD (approx. an additional 0.7m max.) with a new brick wall facade and install flood gates at the various beach access points. In front of Common – Replace existing seawall with a sheet piled wall with concrete facing and capping beam (piling through existing revetment, burying the existing wall under the newly raised promenade) to 5.8mAOD (approx. 0.8m higher than existing seawall). Raise the level of the promenade and beach huts with a landscaped embankment, tying the elevated promenade back into the Common. Pros: Sea views from promenade and beach huts remain unaffected Improved flood protection to beach huts, Uncle Tom’s Cabin, public toilets and car park Cost prohibitive beach recharge is not required (as new wall will not require support from beach) Enlarged promenade will improve amenity use Beach huts and promenade remain visible from the road Cons: Beach access will have to be enhanced Disruptive to local services/utilities during construction All beach huts will have to be temporarily moved and stored (significant risk of damage) and will not be available for use over the construction period New embankment will change the landscape of the Common Sea views from both Leitrim Avenue and Lodwick will be detrimentally affected Highest initial capital cost Cost ItemValue Initial Construction£6.8m Beach RechargeN/A
Shoebury Common Flood Risk Management Scheme What happens next? Over the next few months we will: -Collate and analyse responses to this consultation to inform the choice of project for which planning consent will be sought. -Seek funding approval for our proposals and, if successful, progress into the detailed design of the proposed works. -We will continue to work with both residents and other local stakeholders to refine the design. Have your say We welcome your feedback on our proposals. During this exhibition please take the time to fill out a feedback form and tell us what you think of the scheme. We will then consider your comments in developing the details of the scheme. If you have any questions please feel free to contact us (see details below). High Tide at Shoebury Common Tel: ext Department for Place Southend-on-Sea Borough Council Civic Centre Victoria Avenue Southend-on-Sea Essex SS2 6ER