Standards and regulations for vegetation management

For public safety, reliability and compliance, we must keep our rights of way well maintained. We are required to meet many federal, state and local guidelines, including those established by the North American Electric Reliability Corporation (NERC). These standards help us serve our members better and ensure the reliability of the bulk electric system.

Who is NERC?

The North American Electric Reliability Corporation is an independent, self-regulatory, not-for-profit organization, whose mission is to ensure the reliability of the bulk electric system in North America. To accomplish their mission, they establish and enforce standards that all electric utilities in North America are required to meet.

Blackouts led to strict standards and fines

Since 1996, three large-scale electric grid failures in the U.S. and Canada were caused in part by trees, including the 2003 East Coast blackout that affected 50 million people. The federal government has since developed mandatory reliability standards, including strict requirements for vegetation management, to help prevent problems caused by tree contact with high-voltage transmission lines. Utilities found to be noncompliant are being assessed significant fines, up to $1 million a day, depending on the severity of the situation.

Standards regarding trees and power lines

NERC standards mandate that no outage can occur as a result of vegetation that could grow or fall into high-voltage transmission lines. This includes those transmission lines which operate at 200 kilovolts and above or lower voltage lines deemed critical. Great River Energy and other electric transmission utilities are responsible for meeting this mandate and ensuring transmission lines are clear from vegetation at all times.

Utilities are being more proactive about trees and vegetation

Great River Energy and the utility industry as a whole have always performed right-of-way maintenance regularly. However, the stricter NERC standards have led utilities nationwide to take a more proactive approach with all of their transmission lines. We have always had a responsibility to maintain a reliable system – and now we also are responsible for avoiding risk of fines that affect rates to our members. That means:

• We are often removing trees within the full width of the right of way on transmission lines where we previously may have allowed certain trees to remain.
• Trees that may have been pruned in the past are now more often being removed.
• We continue to use herbicides, when we have permission from the property owner, as an effective method for preventing re-growth.