CAMPAIGNERS fear the controversial seawall planned for Shoebury Common could cause flooding after a new study suggested it will be made of clay.
The seawall, designed to protect more than 350 homes and businesses in Shoebury from flooding, will be built with 44,000 tonnes of earth extracted from Southend cliffs and stored on Old Gunners Park.
Engineers told Southend Council the earth was granular, allowing rainwater to drain away, but a report by Exposem Site Investigations, commissioned by anti-seawall group the Friends of Shoebury Common, found the material was non-porous London clay.
The council, which took advice from two engineering firms, has insisted the material is granular and safe to use.
Andrew Lewis, the council’s corporate director for place, said: “In order to come to a view on the material used for the sea defence scheme, the council has taken detailed and comprehensive advice from two separate expert engineering companies, Buro Happold and Halcrow.
“The initial assessments by BH involved boring 35 holes into the cliffs, up to depths of 50 metres, for close inspection of the material and installation of measuring equipment.
This helped to inform the detailed ground investigations report which runs into hundreds of pages and includes detailed analysis and information.
“The material is currently stored in two piles, one of which is predominantly granular material and the second of which is clay.
“This segregation was part of the works carried out as part of the cliffs slip project. It is not surprising a small random survey sample would find pockets of clay in the larger pile and in the smaller pile which, as explained, is a pile of clay.
“It should also be said that claims of clay not being appropriate for sea defence are not accurate. For example, the embankments to the sea defence at Chalkwell are constructed from imported clay and do not create the type of problems FOSC suggests.”
More than 2,000 people have called for a public inquiry into the council’s handling of plans for a seawall in Shoebury.
The Friends of group have launched a petition calling on the Government to investigate why the authority agreed to build the 7ft wall on Shoebury Common despite huge public opposition.
The petition can be signed at Uncle Tom’s Cabin, on the common, or at http://epetitions.direct.gov.uk/ petitions/ 64056