This environmental impact assessment for Kriegers flak ... - Vattenfall

12 SUMMARY
any protected values or species. The effects of the
nearby surroundings will therefore be limited.
An account of expected environmental effects during
the building, operational and dismantling phases is
made below.
The building phase
Noise and vibrations from working vessels and from
foundation work may scare Þ sh and mammals. As the
building phase is limited in time, the impact is expected
to be small.
Occurrence of mud and changed sedimentation
may lead to fauna, animals living on the seabed, Þ sh
roe and fry being covered. This may lead to reduced
growth or, in the worst case, death. Clouded water
may lead to habitat changes for mobile species. The
volume of sediment that will be stirred up during the
construction work depends on the seabed conditions.
The impact is limited in time. There are no protectionworthy
species or biotopes to any great extent. Impact
due to clouding and sedimentation is therefore judged
to be small.
Operational phase
The wind farm will have an impact on the landscape
picture but as the wind farm hardly will be visible from
the shore during daylight, the disturbance onshore
is judged to be small. Whether hazard lights on the
turbines will be visible from the shore during the night
is still not clear as the regulations regarding hazard
lights currently are under review. From closer view, the
turbines will dominate the landscape picture.
The risk of birds colliding with the turbines is
regarded as small since studies have shown that birds
make way for offshore-based wind turbines. This has
also been conÞ rmed through the studies on collision
risks for birds that Sweden Offshore has commissioned.
The risk of ships colliding with wind turbines is
also regarded as very small (0,0006/year or about 1
700 years between two collisions without increased
safety measures and 0,00015/year or about 6 700 years
between two collisions with increased safety measures
being adopted). If an accident occurs, the negative
consequences could be severe.
From the point of the knowledge base of today, the
reaction of Þ sh from underwater noise is judged, in the
worst case, to be local. Noise could lead to Þ sh avoiding
the immediate neighbourhood. It will however in
such case be possible for Þ sh getting used to the noise.
If a security zone is established within the designated
area, this could lead to very positive effects for the
Þ sh population. A restriction would result in short term
negative effects for the Þ shing industry, but would
have positive effects in the longer term (amongst others
through a so called spill-over effect).
Finally, the impact on the salt water level is judged
to be negligible.
The dismantling phase
The impact during this phase will be similar to that
occurring during the building phase. There will be less
noise, less vibrations and sedimentation as the part of
the foundation that is below the seabed level will be
left in the ground.
Grid connection
The grid connection will be carried out in two phases.
During phase I, a 340 MW cable will be connected
to the grid point Trelleborg Nord and during phase II,
a 300 MW cable will be connected to the grid point
Arrie. The grid connection will be made with 4 threephase
sea cables and 4 three-phase land cables, all AC.
The cables will be trenched some 0.8 meters into the
seabed. Onshore, land cables will be used. Two transformer
stations will be built within the designated area
for the wind farm.
As several countries will build grid connections to
the Kriegers Flak area, there are good opportunities
to make better use of the total investment by allowing
transmission between the countries. A proposal is that
this aspect should be considered in future deliberations
and that the potential be analysed closely.