Drilling to begin for sea defence project

Scarborough Borough Council has announced the investigations centred on the town’s South Cliff Gardens will be conducted over a four-week period from early September to collate information for the £16.6m defence scheme.

The defence project which will transform Scarborough’s South Bay has provoked a wave of controversy after its design was whittled down from six to two options.

An initial £22m stepped concrete revetment with a wave wall has been shelved in favour of a £16.6m rock armour option, and the drilling work will provide vital data for the revised proposals.

The council’s cabinet member for harbours, assets, coast and flood protection, Coun Mike Cockerill, said: “An awful lot of data has already been collected, but this will provide even more indepth information.

“Coastal communities around Britain are faced with significant challenges in relation to the threat of rising sea levels and climate change.

“This drilling work will help protect what is such an important area of Scarborough around the South Cliff Gardens, and it will give us extra confidence in the overall scheme.”

The investigations, which are being paid for through a £290,000 grant from the Environment Agency, will see a series of boreholes drilled through the cliff up to a depth of about 130ft.

The council has admitted the work will lead to some disruption due to the temporary closure of footpaths in the South Cliff Gardens, but maintained the measures were necessary to allow the drilling to be carried out.

Three boreholes will also be drilled up to 65ft deep through the promenade in front of the town’s Spa to determine the depth of the bedrock.

Extra monitoring devices to complement existing equipment in place since the 1990s will be installed in the new boreholes to measure groundwater levels and movements within the cliff. The monitoring devices will be checked for an initial period of six months to provide data for the design of the coast protection scheme.

Samples will be taken during the ground investigations, which will include soil samples and rock cores. The samples will be tested in specialist laboratories to provide data on the composition and strength of the materials in the ground.

A coastal defence strategy was adopted in 2007 amid growing concerns there could be a major landslide as the existing sea defences are deteriorating.

If a landslide did happen, it is likely the sea wall would be overrun and destroyed completely – a scenario which was played out during the notorious Holbeck Hall landslip in 1993.

The cliffs behind the Spa are made of clay and soil deposited during the last Ice Age, and contain small areas of sand and gravel – a relatively soft material which sits on top of the harder bedrock.

Ground investigations will help classify the layers of the different types of material within the cliff and identify where slips and failures could occur, though there are already visible signs of ground instability.

It is hoped a draft plan for the sea defence project will be finalised by the start of next year, when it will be discussed by senior members of the council’s cabinet. The draft proposals will then be submitted to the Government in a bid to secure funding.

Coun Cockerill stressed that while hopes remain the vast majority of funding will be secured from Westminster, the council has put in place contingency plans to draw on its own financial reserves to help pay for the project.