WFD-compliant dredging and Article 4(7) A practical methodology with lessons for other sectors

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1 WFD-compliant dredging and Article 4(7) A practical methodology with lessons for other sectors Presentation by Jan Brooke*, Environmental Consultant 13 th June 2013 Prepared with Greg Whitfield, Environment Agency (England) * Also, for PIANC, WFD Navigation Task Group Chair

2 Presentation overview Introduction to the Environment Agency s Clearing the Waters methodology Maintenance dredging Capital (new) dredging Implications for decision making Case studies of applying Clearing the Waters Ensuring WFD compliance and Article 4(7) Personal reflections 13 th June

3 What is it? Clearing the Waters A methodology, developed by the Environment Agency in collaboration with the UK sea ports sector, to demonstrate whether navigation-related marine dredging activities are WFD compliant How does it work? A standard methodology is available on the Environment Agency s website for use by both applicants and regulators. An application to the Marine Management Organisation for a licence to dredge/dispose of dredged material has to be accompanied by a compliance assessment Is this the same as an Article 4(7) assessment? No, but it may conclude a 4(7) assessment is needed 13 th June

4 Methodology: maintenance dredging Is the proposed maintenance dredging the same as that carried out in the WFD classification period? If no, treat activity as a capital (new) project If yes, the activity is part of the baseline so it is assumed that continuation will not cause (further) deterioration from the current status Is the water body at good ecological and chemical status, including relevant protected area characteristics? If yes, no further assessment is needed If no, is dredging likely to be a causal factor? If yes, carry out an assessment of possible effects If no, can dredging contribute to an improvement? 13 th June

5 Methodology: capital (new) dredging For each WFD element (biological, hydro-morphological, physico-chemical, etc.) and sub-element, determine whether there is a possible causal mechanism for a non temporary* effect on status at water body level* * CIS Guidance Document 20, Exemptions to the Environmental Objectives In other words, could the proposed activity cause deterioration between status classes* of one or more (sub-) elements, or otherwise affect the achievement of WFD objectives in the water body? Using Clearing the Waters, reference should be made to dredging-specific trigger tables - high level thresholds designed to indicate whether assessment is needed 13 th June

6 Applying Clearing the Waters: key considerations Need to understand current status and future objectives for the water body, taking into account each (sub-) element (e.g. phytoplankton, other aquatic flora, benthic invertebrates, depth, freshwater flow, salinity, temperature) to determine whether the proposed activity could have an effect on status Where an effect is possible, carry out investigations, for example include the (sub-) element in the scope of an EIA or undertake a WFD-specific assessment For water related protected areas, consider adequacy of EIA or undertake a WFD-specific assessment Remember the WFD significance test criteria Consider proven and effective mitigation measures 13 th June

7 Implications for decision making Level of assessment to be appropriate to identified risk If a non-temporary effect on status at water body level is possible (i.e. there could be deterioration between status classes or achievement of WFD objectives could be compromised) review mitigation options If there is no effect on status (with proven and effective mitigation measures in place if appropriate), the licence or consent can be issued If WFD ecological status will be affected by a capital (new) project, consider the possible applicability of the Article 4(7) exemption If Article 4(7) tests are met the licence or consent can be issued. If not, use of the exemption is not possible and the licence or consent should not be issued 13 th June

8 Case study: Mersey maintenance dredging Mersey transitional water body Trailer suction hopper dredger with disposal 20km offshore Typically 150,000 tonnes silt; 35,000 tonnes sand dredged from water body 3x per annum HMWB navigation, fisheries; 80km 2 Water body at moderate ecological potential; fails on dissolved inorganic nitrogen; tributyl tin (TBT); sediment management Various protected areas 2015 target: moderate potential 13 th June

9 Mersey: applying the methodology Trigger tables confirm that dredging does not affect dissolved inorganic nitrogen (or Nitrates Directive) status TBT levels in sediment are below CEFAS action level 1 and disposal at sea is approved. Maintenance dredging will neither cause deterioration nor affect ability to meet WFD objective for TBT Sediment management GEP measure is now in place Mersey Estuary SPA and Mersey Narrows pspa: WFD condition is favourable; maintenance dredge protocol confirms no effect on designated site status Up and downstream water bodies: no effect mechanism Aim to improve? Conclusion: dredging is WFD compliant. No further WFD assessment is necessary 13 th June

10 Case study: Heysham capital dredging Morecambe Bay and Duddon Sands coastal water body Proposed to dredge 70,000 tonnes with a backhoe dredger; disposal to sea HMWB fisheries; 390km 2 Water body at moderate ecological potential; fails for phytoplankton; fisheries-related mitigation measures are under investigation Relevant protected areas under Birds/Habitats, Shellfish, Bathing Waters and Nitrates Directives 13 th June

11 Heysham: applying the methodology WFD compliant maintenance dredging 525,000 tonnes annually Phytoplankton screened-out; no mechanism for effect on other BQEs Removal relatively small quantity recent accumulation: only local effects on depth, bed, transparency, oxygen Sediment suitable for sea disposal Only protected area issues relate to microbiological contamination Habitats favourable WFD condition 13 th June

12 Heysham capital dredge: conclusions No non-temporary effects on status at water body level No mechanism for effect on protected areas Proposed capital dredge will not cause deterioration or compromise achievement of WFD objectives No real scope to contribute to improvements in status Project is WFD-compliant 13 th June

13 Mitigation measure examples Issue (1): proposed disposal to sea of material dredged from a small transitional water body would exacerbate coastal squeeze, resulting in non-temporary deterioration of intertidal zone structure and/or other aquatic flora; also impact on Habitats Directive protected area Mitigation: in-estuary disposal e.g. direct intertidal placement or feeder berms as an alternative to sea disposal. Outcome: no effect on WFD status Issue (2): plume of suspended sediment resulting from dredging process could affect fish fauna at a critical stage in the species life cycle thus potentially contributing to deterioration in status Mitigation: select alternative dredging method or programme the dredging activity outside the critical months. Outcome: no effect on WFD status 13 th June

14 Article 4(7) criteria All practicable steps to mitigate effects Reasons for modification set out in RBMP Reasons of overriding public interest or project benefits outweigh WFD benefits foregone No technically feasible, not disproportionately costly, environmentally better alternative All criteria must be met Must also meet Articles 4(8) and 4(9) regarding adjacent water bodies and consistency with / same level of protection as other EC legislation 13 th June

15 Conclusions: a personal viewpoint WFD aims to deliver protection and improvement of the water environment, not to add bureaucracy for bureaucracy s sake! All projects which could affect ecological or chemical status include early consideration of WFD compliance, at an appropriate level of detail, and including mitigation options This process might identify a need to apply Article 4(7) However, if there are no effects on status, including proposals where proven and effective mitigation is incorporated into project such that there is no residual effect on status, the WFD objectives are achieved and the Article 4(7) tests should not need to be applied Clearing the Waters provides a practical example of a methodology for demonstrating WFD compliance 13 th June

16 Thanks for listening! 13 th June