Can dredged canal sediments be used for flood defences as part of the Scottish circular economy?

The vision of a circular economy is to limit environmental damage through waste elimination. This is only possible through intensive recycling and the elimination of waste streams via beneficial reuse, with a corresponding reduction in the estimated 10.7 Mg CO2 emissions per capita in Scotland (Pratt, Lenaghan et al. 2016). Sediments dredged from Scotland’s four operating canals represent a waste stream that can be potentially utilized, providing its geotechnical properties can be optimised and any residual environmental concerns, such as sediment contamination, can be addressed. Scottish Canals currently remove around 4,000 tonnes of material per year to maintain canal depth and navigability through the canal network. Over 99% of EU marine sediment is dumped at sea, representing a lost opportunity to reuse or recycle materials for use in engineering works to prevent flood risk or erosion under climate change scenarios.