Sedimentation of waterways within the proposed 92sq km
Project Hayes wind farm site will likely increase due to
construction of the development, an Environment Court appeal
hearing was told yesterday.
Otago Regional Council water resource scientist Matthew Dale
gave evidence about how sedimentation would be affected by
Project Hayes, and whether increased sediment could be
mitigated.
In response to a question by Judge Jon Jackson, Mr Dale said
sedimentation would be increased by earthworks during the
project's construction phase.
He said stock grazing on the site caused sedimentation of
waterways alone.
But if construction of the wind farm took place while stock
continued to graze, there would be a corresponding increase
in sediment.
Mr Dale said methods of mitigation proposed for controlling
sedimentation on site would be effective.
However, during cross-examination from appellant Ewan Carr,
Mr Dale said he would be concerned about increased
sedimentation if large rain or snow falls occurred on site
and restricted access to certain areas, hampering mitigation
or maintenance measures.
Mr Carr believed there was the possibility of "catastrophic"
failures in planned mitigation, resulting in sedimentation
increases.
