CRT Trials New Way of Processing Dredgings13 May 2015
CRT has opened a pilot dredging treatment site near Coventry as part of its plans to carry out £80m worth of dredging over ten years. With new legislation, the cost of disposing of dredging via landfill has increased dramatically in recent years, and the site should provide a cost efficient place to process dredgings that are not suitable for other uses, such as being spread onto agricultural land or re-profiling eroded canal banks.
It is now illegal to take ‘wet waste’ to landfill, so CRT has decided to explore other avenues of processing dredgings. Because of the nature of the charity’s dredging work, which can result in lots of material being dredged at once, it is difficult and costly to find companies to take the dredgings. At the treatment site, CRT is trialling various methods of drying out the dredgings, which will then be reused or, if they are contaminated, safely taken to landfill.
The site has been set up in partnership with Land & Water and FCC Environment Ltd, and the trial is part of investigating the need for, and viability of, setting up a network of such sites. The first 3,500 tonnes of dredged material was taken to the new site in March (with more arriving throughout the year). CRT plans to monitor how quickly and efficiently the material dries out.
The site includes drying lagoons that drain the wet dredgings. This opens up opportunities for a range of uses for the dredged material including landscaping, capping for landfill sites and use in land restoration. The volume of material should dry down by a third on average, which reduces the amount going in to landfill, and the associated costs.
Photo: CRT dredging treatment site