Sammamish-Maple Valley Line No. 1/Monroe-Novelty Line No. 1

Tree clearance

Typically, BPA will clear trees to the edge of its right-of-way, which extends 75 feet from the transmission line’s centerline, to maintain the reliability of the line and safety of BPA’s line crews and the public. However, because this line was leased and maintained for the last 50 years by a third party that cleared a smaller distance from the centerline, BPA is planning to reduce this clearance area to 62.5 feet from the centerline, and will evaluate the vegetation removal needs in areas where vegetation exists in the area between 62.5 and 75 feet from the centerline.

However, BPA will remove vegetation within any right-of-way that represents either an imminent or potential danger of coming in contact with the transmission lines or towers.

Use of herbicides

BPA applies herbicides along its right-of-way only when necessary to supplement other methods of clearing such as cutting and mowing. Additionally, BPA endeavors to use the least toxic herbicides commercially available – in this case, Garlon 3A.

If you have a wellhead that is within 164 feet of the right-of-way, or if you are interested in protecting other sensitive areas (e.g., a community garden) from herbicide use, please call us at 1-800-836-6619 or email When leaving a message, please include details regarding the exact location of the area of your concern, your current contact information, and reference the “Sammamish-Maple Valley and Monroe-Novelty transmission lines.”

Environmental analysis

BPA’s vegetation management program complies with all applicable environmental laws and Department of Energy regulations, and BPA completed an environmental impact statement for all of its transmission corridors across its service territory in 2000. Additional environmental review of any proposed site-specific vegetation management is also performed in advance of any actions. BPA completed an additional environmental review of the Sammamish-Maple Valley and Monroe-Novelty Hill transmission corridor in September, 2018. The environmental reviews for projects are available on BPA’s website at or you can go directly to this link for the environmental supplement analysis (SA-694) for these two transmission lines.

BPA takes great care to balance operational, reliability and safety needs with BPA’s commitment to environmental sustainability. BPA has been recognized in North America as best-in-class for its vegetation management practices.

Timeline of work along Sammamish-Maple Valley and Monroe-Novelty Hill 

Comments or questions

If you have general comments or questions about this project, please email or call 1-800-622-4519. If you are a property owner with land on or very near the right-of-way, please call 1-800-836-6619. Be sure to reference "Sammamish-Maple Valley", " Monroe-Novelty", or "End of Lease Line Reintegration" when leaving a message, and please leave a number and best time to return your call.

Frequently Asked Questions