The Problem
Heavy flooding had washed away the stream bank close to the property, taking with it a large part of the fill and foundations from under the house. Site investigations established solid ground conditions at 2m below the top of the existing stone foundation and that approximately 35m3 of ground had been washed away. Consultations were held with Ceredigion County Council Land Drainage/Flood & Coastal Management/Planning Liaison Officer and the necessary permission was granted for a two-phased repair solution to include structural repairs to the property followed by repairs to the garden and stream banks.

The Optera Solution
To return the integrity to the building it was agreed that the complete front elevation would require underpinning. Optera designed a sequence of underpinning which included a mechanism to release hydrostatic pressure from beneath the house. This comprised 50mm underground pipes laid at 500mm centres through the underpins to alleviate hydrostatic pressure behind the wall and discharge it into 110mm pipes falling towards and discharging into the stream. Future flood protection to the property was provided by the installation of 24 stone-filled gabion baskets and strategically placed rock armour on the banks of the stream.

Project Conclusion
On completion the Ceredigion County Council Land Drainage/Flood & Coastal Management/Planning Liaison Officer commented: “For us, as officers of Ceredigion County Council, it was a pleasure to work with such professional and helpful contractors, with a highly skilled workforce supervised and lead by a very professional site manager.”

“Future flood protection to the property was provided by the installation of 24 stone-filled gabion baskets and strategically placed rock armour on the banks of the stream.”

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