On basis off following extensive environmental investigations, the Danish Energy Agency gave Sund & Bælt the go-ahead for the Sprogø Offshore Wind Farm project.
The environmental investigations have clarified the extent to which the turbines will impact on the area’s flora and fauna, both during the construction and operational phases. Throughout the construction phase, the environment was closely monitored and the investigations were continued after the wind farms establishment.
Common porpoise
As one of Europe’s largest populations of common porpoise is found in Storebælt, the environmental investigations especially focused on the project’s impact on the species. Impact on the common porpoise was expected to be limited, and was primarily during the construction period.
In order to protect these animals to the greatest possible extent, the construction of the turbines start after the porpoises’ breeding season in mid-August. On behalf of Sund & Bælt, Denmark’s National Environmental Research Institute (DMU) carried out a porpoise monitoring programme during the entire construction phase in order to record the impact on the animals’ habitat.
Birds and toads
There is extensive focus on the effect on the area’s many birds, particularly the migratory common eider and breeding sandwich tern. These species form the basis of the Bird Protection Area 98 that borders the wind turbine farm and covers the whole of Sprogø and the waters around the area. The environmental investigations have shown that impact on birds would be so slight and temporary that it was of little significance for the area’s bird population.
During the construction phase, an investigation area of 1 km x 4 km, running parallel with the bird protection area’s northern boundary, was sealed off, as will an approx. 400 m wide investigation area into Sprogø. The contractors had been requested to ensure that traffic to and from the exclusion zone followed the designated navigational corridors. This requirement had been agreed with the environmental authorities in order to reduce impact on the bird protection area.
On Sprogø, special attention was given to protected species such as the green toad. A toad fence has been erected in connection with the excavation work in order to keep the toads away from the excavation machinery and the excavations.
Impact on the seabed
While the excavations for the foundations and cables was a result in a temporary loss of benthic fauna and mussels, once the wind farm was completed, animal life will rapidly re-establish itself. As was seen at the Storebælt Bridge’s bridge pillars, the turbine’s foundations can help to improve the marine environment by providing a favourable growing base for algae and mussels which provide feed for the animals higher up the food chain.
Fishing
Under the Fishing Act LBK no. 371 of 24 April, 2006, negotiations must be conducted with the fishery organisations concerning compensation for documented loss of earnings as a result of the wind farm’s construction. Since September 2008, meetings have been held with the Belts’ fisheries association and on March 2, 2009, a settlement was reached concerning damage to fishing during the construction and operational phases.
