Apart from initial difficultés with the first ramming work, Ballast
Nedam Offshore were able to meet the noise limits set without
difficulty from the seventh monopile onwards. Acoustic signais
were also used before the pile-driving work began in order to
keep the porpoises away from the construction site.
In the autumn of 201A, only a few months after the ramming
work for the foundations had been completed in a timely manner, the final report on the monitoring of the porpoises during
the foundation phase was already available. "Our basic findings
showed that more porpoises are to be found in the area of the
Butendiek offshore wind farm in the summer months than in the
winter season. In 201A we counted the same number of animais
as in the previous year, but there was a significant departure from
areas of the sea in a radius of four kilométrés around the monopiles", the report reads. This means that the porpoises chose to
avoid loud construction areas of their own accord but returned
within a few hours of the pile-driving work being completed.
The final report also established "that scaring off the porpoises
from nearing the construction site was very successful with the
resuit that damage to porpoises from ramming noise can be
ruled out. Further recordings of porpoises indicate that the piledriving work had a short-term effect on the distribution of the
porpoises, but there are no noticeable changes in the population
in the area under investigation."
The technical and logistical efforts undertaken to achieve this resuit were enormous. During the construction phase, the teams
out in the North Sea were in permanent contact with Dr. Susanne
Schorcht in Bremen.
NEVER BEFORE HAS SUCH EFFORT BEEN PUT INTO AN OFFSHORE WIND PROJECT TO SUCCESSFULLY REDUCE THE
NOISE EMISSIONS BELOW THE 160 DB LEVEL WHICH RE~
PRESENTED A TARGET AS AMBITIOUS AS IT WAS NECESSARY.
91
Nedam Offshore were able to meet the noise limits set without
difficulty from the seventh monopile onwards. Acoustic signais
were also used before the pile-driving work began in order to
keep the porpoises away from the construction site.
In the autumn of 201A, only a few months after the ramming
work for the foundations had been completed in a timely manner, the final report on the monitoring of the porpoises during
the foundation phase was already available. "Our basic findings
showed that more porpoises are to be found in the area of the
Butendiek offshore wind farm in the summer months than in the
winter season. In 201A we counted the same number of animais
as in the previous year, but there was a significant departure from
areas of the sea in a radius of four kilométrés around the monopiles", the report reads. This means that the porpoises chose to
avoid loud construction areas of their own accord but returned
within a few hours of the pile-driving work being completed.
The final report also established "that scaring off the porpoises
from nearing the construction site was very successful with the
resuit that damage to porpoises from ramming noise can be
ruled out. Further recordings of porpoises indicate that the piledriving work had a short-term effect on the distribution of the
porpoises, but there are no noticeable changes in the population
in the area under investigation."
The technical and logistical efforts undertaken to achieve this resuit were enormous. During the construction phase, the teams
out in the North Sea were in permanent contact with Dr. Susanne
Schorcht in Bremen.
NEVER BEFORE HAS SUCH EFFORT BEEN PUT INTO AN OFFSHORE WIND PROJECT TO SUCCESSFULLY REDUCE THE
NOISE EMISSIONS BELOW THE 160 DB LEVEL WHICH RE~
PRESENTED A TARGET AS AMBITIOUS AS IT WAS NECESSARY.
91