Seattle City Light is required to manage the vegetation and nearby structures that are adjacent to or under our high voltage electric transmission power lines. These items can present significant problems for the high voltage transmission lines, even if they are only adjacent or in the vicinity of the lines. The North American Energy Reliability Corporation (NERC) can impose large fines and penalties on utilities such as Seattle City Light if we fail to perform proper vegetation and structure management to ensure that vegetation and/or structures don’t interfere with, impede, or come in contact with high voltage electric transmission lines.
To maintain compliance with NERC requirements, Seattle City Light will maintain, and in some instances remove, vegetation that presents hazards to the high voltage electric transmission power lines or are incompatible with electric industry standard practices.
Update July 1, 2011: City Light Vegetation Management has completed a vegetation clearance
project in Renton under and adjacent
to the Maple Valley Transmission
Line at Eagle Ridge. A crew removed
more than 100 trees on 1.3 acres and
completed brush clearing, grading,
and seeding the week of June 3, 2011.
City Light will plant low-growing
native plants on the site in the fall,
reducing the need for continuous
tree trimming in the area and
providing wildlife habitat.