IWDG concerned about EIA for offshore windfarm of County Wicklow

The IWDG have prepared a detailed submission expressing concern about the impact of the proposed Dublin Array offshore windfarm on harbour porpoise and other cetaceans in the area. The Dublin Array will comprise 145 turbines with a maximum  blade tip heght of 160m and cover an area of 54km2 around 10km off the Wicklow coast.

The IWDG is in favour of renewable energy and is not opposed to windfarms being constructed in the marine environment. However construction and operation of these windfarms should be in line with best practice and should provide robust evidence that any impacts are short-term and not significant and do not degrade habitats for cetaceans or impact on cetacean populations.

IWDG are concerned that the site survey was not carried out in suitable sea conditions and thus the conclusion that porpoise densities in the area are low cannot be corraborated.

IWDG are concerned that the noise during construction will be significant and adversely affect the proposed Rockabill to Dalkey Island candidate Special Area of Conservation has been carried out. This SAC has harbour porpoise as a qualifying interest and is the only protected site for this species on the east coast. The Natura Impact Assessment states that “the project is not directly connected with, or necessary to the management of, any Natura 2000 site”. The impact of activities up to 15km away from Natura 2000 sites should be considered if there is the potential for an impact on the qualifying interests. This project is directly connected to the proposed Rockabill to Dalkey Island candidate Special Area of Conservation and adjacent sites have some of the highest porpoise density estimates ever recorded for the species in Ireland. The proposed work in the area adjacent to this proposed cSAC is worrying as previous work in Germany has shown harbour porpoises demonstrated a strong avoidance behaviour up to 20km from pile driving so this project is very much connected to the adjacent proposed cSAC. The IWDG question whether it is acceptable that up to 40% of a cSAC for harbour porpoise will be affected by to a level that may cause aversive reaction in harbour porpoise.

The appropriate assessment suggests that “the return to pre-piling levels (of harbour porpoise activity) is expected to occur within hours or days following cessation of piling”. Studies at offshore wind farms in the North Sea showed that it took two years for porpoise activity in the area to return to pre-construction levels. No Static Acoustic Monitoring was carried out in line with best practice to determine porpoise activity pre-construction to enablee assessment of the changes and recovery of porpoise activity post-construction.

The EIA states that four cetacean species are regularly occurring in the affected area. The EIA largely omits and fails to consider minke whales which occur regularly in the affected area or bottlenose and Rissos dolphins which are more transient.

The IWDG considers this proposal as presented is likely to have a significant impact on a Natura 2000 site and thus should not be given permission to proceed. Based on the Habitats Directive, legal protection from a designated site extends 20km, therefore the proposed work will have an impact on the integrity of the pc area. Therefore, with the information currently available, it is not possible to determine the extent at which porpoises will be impacted upon. Additionally, Ireland will not be contravention of the requirements of designated areas and protected species as set out in the Habitats Directive.

Submission prepared by Dr Simon Berrow, Dr. Joanne O’Brien and Dave Wall on behalf of the Irish Whale and Dolphin Group. The full submission can be downloaded here: