It can also cause greater erosion of river banks, which “can be a major hazard for infrastructure such as bridges”. In a 2014 report on the issue, CIWEM noted that dredging rivers can even increase the flood risk for communities downstream, by “speeding up the movement of floodwater through the river and drainage network”. However, he said that for most areas where flooding has occurred, dredging would not be effective, as the floods come from fast-flowing rivers where sediment build-up is less of an issue. In a blog post for the Environment Agency last week, the Director of Policy for the Chartered Institution of Water and Environmental Management (CIWEM) said that dredging can help in some situations-for example on the Somerset Levels (although more dredging would not have fully prevented the floods the Levels saw in 20). A report from the dredging industry (written prior to the Water Framework Directive’s implementation) suggested these considerations do have an impact, but that overall much depends on how individual EU member states implement the directives.īeyond this, it is far from clear that dredging would be a solution to much of the flooding seen in recent years. The Waste Framework Directive, meanwhile, has effects on how the silt is disposed of. For example, the EU Water Framework Directive affects elements of dredging such as evaluation as to whether dredging activities could affect wildlife. However, some EU regulations can affect dredging decisions. The European Commission has said more than once that EU law “does not ban dredging”, and the fact that it isn’t banned can be seen from the fact that dredging is still carried out in the UK. This creates more space and in theory, this means when an area experiences heavy rainfall, there is greater capacity to accommodate it. A Facebook post claiming that recent floods in the UK were because the EU does not allow dredging has been shared numerous times on Facebook and Twitter.ĭredging is the process of removing silt, mud, and other debris at the bottom of bodies of water.

What is dredging a river