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Dredging

Volume 465: debated on Thursday 25 October 2007

To ask the Secretary of State for Environment, Food and Rural Affairs (1) whether assessments of dredging applications take into account possible risks to neighbouring sites, such as estuaries; (160811)

(2) what assessment he has made of the effects on the Dee Estuary of dredging neighbouring sites.

The control of dredging operations depends upon the type of dredging involved.

Port and harbour authorities generally have provisions under their local powers (granted by means of Harbour Orders) within their jurisdiction to carry out or to license others to conduct dredging activities—primarily for the purpose of securing or maintaining a safe navigation depth. Other dredging operations which may cause or be likely to result in obstruction or danger to navigation require consent under the Coast Protection Act 1949 (part II). Any disposal or beneficial placement of dredged arisings at sea is subject to licence control under the Food and Environment Protection Act 1985 (part II). In certain cases, dredging activity may also require consent under the Land Drainage Act 1991.

Regulatory authorities, in dealing with such applications to dredge, have a duty to consider if the proposed project, because of its nature, size and location will have a significant environmental effect. If so, the application must be accompanied by an Environmental Statement and its determination will be subject to an environmental impact assessment—normally in accordance with the Marine Works (Environmental Impact Assessment) Regulations 2007. Environmental Statements are scoped to address all the aspects of the project which may be affected by the project, including, typically in the case of dredging:

i. impacts on the physical environment, including coastal and estuary morphology, hydrodynamics, sediment transport, water quality and the fate of disposed materials

ii. ecological effects, on fish and other flora and fauna arising, for example, from removal of sea bed species/habitat, the mobilisation of any contaminants, noise and changes to the physical environment

iii. risk to protected conservation sites and other sensitive sites

iv. impacts on birds—especially to those dependant on inter-tidal areas and disturbance to marine mammals

v. interference to the interests of others using the sea and their assets, including other commercial uses, leisure activities, fishing, subsea cables and marine archaeology

vi. the in-combination and cumulative effects of other works.

Many potential dredging areas also lie within or adjacent to the boundaries of designated European conservation sites. If the regulating authority consider that the dredging project is likely to have a significant impact on such a site, an appropriate assessment of the possible risk to the integrity of that site must be carried out in compliance with the Conservation (Natural Habitats &c) Regulations 1994.

The commercial exploitation of sand and gravel (aggregate dredging) is regulated under the Environmental Impact Assessment and Natural Habitats (Extraction of Minerals by Marine Dredging) Regulations 2007.

In 2001, applications were made by the port of Mostyn to conduct dredging operations within the inner and outer approach channels to the port. A consultation paper was issued under a public notice summarising the assessments conducted by the regulating authorities.

Authorisations were granted by the regulators in the summer of 2005 for a limited dredge over a period of two years. Each of the approvals granted were subject to conditions that included a rigorous programme of monitoring, the results of which are currently being assessed.