Aquatic Environment
Another major issue that has been voiced
is the threat of offshore
turbines on the aquatic environment. Environmentalists, local fisherman and
government officials have expressed a concern for the impact of wind turbines
both during construction and operation.
Concerns such as the impact of the turbines on the seafloor, the
potential for magnetic fields from underwater transmission, impact on fisheries
and geological impacts were recently studied as part of the Draft Environmental
Impact Statement for the Cape Wind Project off of the coast of Nantucket
addressed a number of issue with the following findings:
1)
Geology
– No major impacts on the wave conditions, water temperature and currents. In addition, it found that the project would
have only temporary localized effects on the water depth and sediment transport
2)
Benthic and Shellfish resources –
“….localized temporary impact on the benthic community” and limited shellfish
mortality associated with construction.
3)
Commercial Fisheries – minimal
displacement of finfish due to construction with “…impact to fish from normal
operation of the WTGs would be minimal.”
Given the consistency of the
surrounding environment, most organisms would be able to relocate to a similar
environment.
4)
Underwater sound – The anticipated decibel
level beyond the 500m Safety Radius is expected to be below the 180dBL
threshold for preventing injury to turtles and aquatic mammals.
5)
Water Quality – Sediment in the water
column would be increased during construction, but is expected to return to
normal soon after. Studies of the local
sediment did not indicate any pollutants that may become resuspended during
construction.
6)
Electromagnetic Field – Any magnetic field
would be blocked by grounded metallic shields in the transmission lines.
While
the Cape Wind sight is a sandy bottomed sight in the northeast, the issues
addressed in this EIS reflect typical environmental issues with offshore wind
turbine construction. Thus, if attempts
are made to avoid fragile or immobile marine habitats, minimize sediment
suspensions as well as other typical marine construction mitigation techniques
(limiting spills etc.), the effects to the aquatic environment should be
minimal and localized.