The Environment Agency has revealed plans worth £35million for a Canvey Island flooding project to replace nearly 70-year-old defences.
On Thursday, September 22, Environment Agency officials presented their plans for the plan to replace 2 miles of revetment from Thorney Bay to the Island Yacht Club.
The Environment Agency’s report on the project states: “This project will better protect the tidal barrier from erosion and extend its useful life to 2070 in the face of sea level rise caused by climate change.
“This work extends into the future the high standard of flood risk protection provided by Canvey Island’s tidal defenses, a key objective of the Thames Estuary Plan 2100.”
The Thames Estuary 2100 plan is a £10bn government funded project.
As part of the plans for the renovated defences, a new revetment will also be built at a lower angle from Thorney Bay to north of Leigh Beck Point and all steps leading to the beach along the entire shoreline will be completely replaced.
In addition, the footpath facing the sea will be widened at “important bottlenecks” and the footpath on top of the dyke wall will be re-asphalted.
Work is scheduled to start in March 2023 and could take up to two and a half years, which the Environment Agency says is crucial to tackling sea-level rise caused by climate change.
Current repairs to the tidal shelter were constructed in 1953 in response to that year’s tsunami which killed 59 and evacuated 13,000 Canvey residents.
As part of a report, the Environment Agency said: “Canvey Island sits very low, with ground levels nearly two meters below daily high water levels in the Thames Estuary.
“This means the entire island is at risk from tidal surges that could affect more than 15,000 homes.”
Other parts of the fairing date from the 1930s, including some of the sections to be replaced.
The Thames Estuary Asset Management (TEAM) 2100 program is an integrated partnership between the Environment Agency, Jacobs and Balfour Beatty, but a contractor for the actual construction has yet to be appointed.
The current facing of Canvey Island is a sloping coastal concrete structure that is crumbling.
The plans for the newly renovated revetment envisage that it will be built of open rock asphalt (OSA).
The Environment Agency said: “The OSA will provide full coverage along the 3.2km front. This means there are no joints in the revetment material. This reduces the likelihood of lost joint material and hence the risk of erosion and material loss under the overlay.
“The interstices between the gravel within the OSA are not completely filled with bitumen, which allows the material to absorb wave energy and reduce the likelihood of material erosion.”
During construction, there is a possibility that public access to the beach may be restricted.
Due to the nature of the construction of a revetment in an intertidal zone, the work must be installed in the low tide window over a five hour period between 06:00 and 22:00.
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