Carnell employed an innovative technique to remove silt from a balancing pond adjacent to the strategic road network. This both restored the capacity and dealt with the waste in a more cost-effective and sustainable way, while improving water quality and the biodiversity of the pond.
National Highways identified that Twigmoor Pond which serves the M180 was in need of maintenance, to restore its ability to deal with stormwater and reduce the risk of flooding events. The capacity of the lagoon had been significantly restricted through the accumulation of silt from highways run-off, with investigations showing 200mm to 800mm of silt across the area of the lagoon, equating to a capacity loss of 3,500 cubic metres – significantly more than the volume of an Olympic sized swimming pool.
As National Highways’ Drainage lot provider in the Yorkshire North East region, Carnell were appointed as Principal Contractor for the scheme. Having understood the challenges, such as access limitations, environmental considerations and moisture management of the recovered silt, they turned to Soilfix, a soil remediation and groundwater remediation specialist.
