Marine minerals dredging in English waters is carefully controlled through the Environmental Impact Assessment and Natural Habitats (Extraction of Minerals by Marine Dredging) (England and Northern Ireland) Regulations 2007. All marine mineral dredging applications are required to assess the physical effects of the proposed dredging operation and its implications for coastal erosion by way of a Coastal Impact Study (CIS). A permission to dredge will only be issued if the regulator (the Marine and Fisheries Agency (MFA) on behalf of the Secretary of State), their advisors, consultees and major stakeholders are content that the proposed dredging is environmentally acceptable. In making this judgment the precautionary principle is always adopted and should the CIS show a potential to contribute to coastal erosion a permission would not be issued.
Modelling and field studies on the impact of both individual offshore dredging licences and of the cumulative impacts of such licences have concluded that UK offshore dredging has not contributed to coastal erosion. There may be a potential impact on the coastline in relation to estuary and near-shore dredging for navigation purposes. However, in these cases, there is a clear need to balance economic and social imperatives of continued port operations with any environmental impact.
Disposal of navigational dredgings in tidal waters is licensed under the Food and Environment Protection Act (FEPA) 1985. Before any licence can be issued for disposal, consideration must be made as to whether alternate waste management options are possible, including re-use. FEPA licences are not normally granted where practicable alternative means of recovery or disposal exist. We are working with the industry to secure ways to ensure the arisings of appropriate dredging spoil are more closely linked to suitable construction projects where re-use would not entail excessive costs.
There have been a number of examples where materials that are to be dredged for navigational reasons have been diverted to alternative use, including for construction, land reclamation and for landscape bunding etc. For example, the Port of Southampton disposed of, for commercial use, a significant quantity of sand dredged from their navigational channels and the proposed London Gateway port development envisages using some 25 million tonnes of dredged materials for land-raising/landscaping works. It is not uncommon for port authorities to make available suitable dredged materials for use in maintaining beaches and inter-tidal areas. Harwich Haven Authority has previously entered into various agreements with local coast defence authorities to re-use suitable sand for beach replenishment.
DEFRA continues to fund research into alternative uses of dredged material to improve understanding of how these can be used and, with its Marine and Fisheries Agency which regulates disposal of marine dredgings, are engaged with the Central Dredging Association (CEDA) to promote and increase beneficial use of materials.