The Tilshead Flood Attenuation Dam was designed to hold 100,000m3 of flood water, improving flood protection for 150 homes and businesses in the village of Tilshead on Salisbury Plain.
The dam was constructed using chalk engineered fill to allow water to percolate and drain away and is the only dam of its type in the UK. An Armourflex matting layer provides a durable erosion protection system to the dam which was then covered with a layer of topsoil to enable the re-growth of local plant life.
The site is within a designated SSSI (Site of Special Scientific Interest) and therefore ecological management of the site was crucial. A barrier around the perimeter of the site prevented wildlife from moving back in during the construction phase, and strict processes were introduced to avoid spillages and leachate within the site boundary.
Situated within a live MOD training facility, added site risks included working near a firing range, unexploded ordnance, and low flying aircraft and therefore the team worked closely with the MOD to minimise disruption and ensure safe operations on our site whilst live ordnance activities continued.