Jefferson County PUD maintains a rigorous tree-maintenance program for trees along power line rights-of-way. Trees are our number one cause of outages and approximately 90 percent of tree-related outages are caused by trees growing outside of the right-of-way
Trees that grow too close to power lines can cause outages, start fires or create other hazardous conditions. Generally, we remove trees that pose a serious threat to safety and electric service. Not only does this work help maintain electric safety and service reliability, it is mandated by state and federal regulations (NESC Rules 012, 013, and 218; IEEE Standard 516-2003, Section 22.214.171.124; ANSI Z133.1; OSHA 1910; and WAC 296-45).
SUBJECT: Right-of-Way Vegetation Management
OBJECTIVE: To state the policy regarding vegetation management
Maintaining adequate vegetation clearance from lines and electric utility equipment is vital to the safe and reliable operation of the electric distribution and transmission system. It is the intent of the Jefferson County Public Utility District (PUD) to maintain proper tree clearance near overhead distribution and transmission lines for safety reasons, to minimize interruptions of electric service, and to provide access for line operations. The PUD will provide cost-effective vegetation management services on a scheduled seven-year maintenance cycle that ensure vegetation clearance from power lines and equipment is consistent with Rural Utilities Service (RUS) and PUD specifications.
The PUD requires that the American National Standards Institute (ANSI) A300 Tree Care Operations standard practices relating to quality tree care, pruning, and integrated vegetation management be followed to the extent possible when planned maintenance is being performed in the vicinity of electric lines and equipment. Employees and contractors shall also adhere to (ANSI) Z133.1 Safety Standards.
I. PLANTING TREES OR MOVING TREES
A. Customers should consider the mature canopy size of trees to be planted on their property. No tree shall be planted that will interfere with distribution or transmission lines when fully grown. Trees that will grow taller than fifteen (15) feet shall be planted at least twenty (20) feet away from pole center for single phase distribution lines and thirty (30) feet away from pole center for multiphase distribution lines. If a customer’s tree is in violation of the required distance, the customer will receive a Tree Transplanting Notice- see Appendix A, from the PUD informing them of the violation allowing them to address the issue timely.
B. Trees shall not be planted within forty (40) feet of pole center for transmission lines. Trees planted closer than this distance may be removed by the PUD.
C. Customers and contractors should contact 811 to locate underground utilities to avoid personal harm and damage to the lines and interruption of electrical service when planting or moving trees. Customers and contractors will be responsible for paying repair costs for lines that are damaged due to digging.
D. Customers shall not plant trees within ten (10) feet of underground cable. Necessary repair of underground lines could cause damage to trees planted near the cable. When planting around pad mount transformers or junction boxes, all vegetation shall be planted at least three (3) feet away from all sides and ten (10) feet away from the access panel.
E. Trees less than 10 feet in height growing near the overhead distribution or transmission may be moved or cut down by the customer to reduce potential safety and service hazards. A customer shall not risk his/her safety by cutting or moving trees taller than ten (10) feet located near power lines
II. TREE REMOVAL AND PRUNING
A. The PUD is responsible for maintaining tree clearance only on power lines owned by the PUD. Responsibility for tree clearance on customer owned lines belongs to the customer. When the line belongs to the customer, hiring of a professional tree service is recommended to ensure customer safety and prevent damage to electric lines.
B. Trees endangering PUD owned lines may be cut down or pruned by the PUD to eliminate any immediate hazard. Trees less than 8” inches in diameter in rural, forested, and agricultural road right of way corridors will be removed with or without the consent of the property owner.
C. The PUD will provide vegetation maintenance along primary lines (those between the substation and the service transformer) and PUD owned transmission lines. The appropriate vegetation management practices will be utilized at the discretion of the PUD’s Special Project Coordinator to achieve required line clearances until the next maintenance cycle. Trees and brush growing within the right-of-way corridor outside of the home landscape will be removed by the PUD. Right-of-way corridors will be managed to ten (10) feet for single phase distribution, twenty (20) feet for multiphase distribution and forty (40) feet for transmission lines to either side of pole center.
Trees outside the right-of-way corridor, which are dead, dying, structurally defective or otherwise pose a danger of falling on the lines (hazard trees) will also be removed.
Landscape trees are trees located within an established lawn area or are ornamental specimens growing within the home landscape. Generally, the main trunk of landscape trees should be ten (10) feet or more from the vertical plane of the wires for distribution lines. Landscape trees will be pruned to provide clearance until the next scheduled maintenance cycle. The pruning distance will depend upon the species, cycle length and location of the tree. Landscape trees requiring repetitive pruning or those which are disfigured while achieving necessary clearance may be selected for removal with the property owner’s consent.
To protect the public from electric injury, a minimum safety clearance from uninsulated conductors shall be obtained on all trees, regardless of location. A Safety Clearance Action Threshold has been established and is outlined in Appendix B. Safety clearance will be obtained with or without the property owner’s consent.
Trees and brush growing in the right-of-way corridor will be cleared to forty (40) feet either side of pole center for transmission lines. If there are mature trees growing within the landscape right-of-way corridor, they may be trimmed, at the PUD discretion, to prevent possible contact between the trees and conductor in the event of falling trees or line blowout created by wind.
D. During maintenance cycle work all trimmings that can be reached will be chipped and removed.
E. When work is necessary because trees have caused a power outage or because trees have died and present a hazard, all debris will be left for disposal by the property owner.
F. Stump removal will not be performed by the PUD
II. CHEMICAL APPLICATIONS
A. Jefferson County PUD uses no chemical applications to manage trees and brush within the right-of-way corridor.
A. Typically, door-to-door contacts, brochures, door hangars, phone messages, and/or electronic communications explaining policies and practices may be used to notify property owners of vegetation management work.
B. No advance notice will be given prior to off-schedule work, including the removal of hazard or storm-damaged trees or power restoration activities.
A. “Hazard Trees”- trees outside the right-of-way corridor, which are dead, dying, structurally defective or otherwise pose a danger of falling on the lines.
B. “Distribution Lines”- a distribution line is as generic term for a distribution voltage (2,400 volts to 35,000 volts) line that carries power from a substation to a residence or business. These lines may be overhead or underground.
C. “Line Blowout”- the distance a power line can be expected to swing during high wind.
D. “Primary Line” – a power line that carries medium voltage power to distribution transformers located near the customers premises.
E. “Secondary Line”- lower voltage lines from the distribution service transformer to the customer’s service (s). The lines may be overhead or underground and may include equipment such as pole-mount utility secondary connectors.
F. “Transmission Line”- a bare, uninsulated, high voltage 69,000 volts to 345,000 volts overhead power line, usually strung from steel towers or tall wood, or metal poles, that carries power for power generation plants to substations.
Employees are responsible for understanding and complying with this policy.
PUD representatives, or other qualified personnel, are responsible for communicating this policy to the customers.
Supervisors are responsible for monitoring and ensuring compliance with this policy. The General Manager is responsible for the overall administration of this policy as it applies to employees.
The PUD reserves the right to change, suspend, eliminate, depart from, or add to all or any part of this policy at any time, with or without prior notice, whenever the board of commissioners or management determines it is in the best interest of the PUD to do so.
We hire certified tree-trimmers to maintain a safe corridor around power lines. They work throughout the county on a multi-year schedule. They use natural pruning methods to maintain the health of the trees. Natural pruning, besides being healthier for the tree, also reduces re-sprouting in problem areas and limits the length of sprouts that do occur. The tree’s species, structure, and the strength of the wood are all considered when trees are pruned.
Our contracting crew never use “round over” pruning because this method wounds the tree and causes it to grow unnaturally. In addition to pruning, trees not intentionally planted as part of the landscape (“natural re-prod”) that measure less than six inches in diameter at 4.5 feet high will be removed.
Pruning clearances depend on tree species and growth patterns, as well as the voltage of power lines in close proximity. Around distribution lines, we provide at least 10 feet of clearance. Fast-growing species common to Jefferson County (ie, willow, alder, maple, and cottonwood) require 14 feet of clearance while slow-growing species (spruce, fir, and cedar) require at least 10 feet of clearance.
If you’d like a tree pruned or removed for landscaping purposes, you’ll need to hire a private arborist or tree removal contractor to perform the work. If necessary, we can disconnect a service line for their workers’ safety.
Sometimes the best solution to tree and power line conflicts is tree removal. We work with neighborhoods to remove problem trees, particularly in cases where they require repeated pruning. Tree removal is especially important where pruning alone cannot achieve safe clearance from power lines.
Along stretches of road where there are no houses, we remove problem trees from the public right-of-way. It saves our customers money to remove them rather than trim repeatedly. We would never remove yard trees without first talking with the homeowner, though we might trim them if we’re unable to reach the homeowner beforehand. We work with the wishes of our customers whenever we are able to without endangering our personnel or the reliability of the system.
Because our tree maintenance activities can have a profound effect on the appearance of trees, the value customers place on high-quality electric service will sometimes conflict with the value they place on trees in their community.
Jefferson County PUD is obligated to keep lines clear to provide power to the community and our customers. We can, as an absolute last resort, pursue legal means.
We do our best to notify property owners of work to be performed ahead of time. We do this as a courtesy. The PUD has rights to the property, which provides us access to maintain our power lines
The cost to install underground lines is $5000 to $10,000 per homeowner, minimum. Underground cable life is typically less than 20 years. Any time a cable fails, Jefferson County PUD would have to dig down and repair the faulted line. In addition, relocating overhead lines to underground cable often destroys a tree’s root system.
NOTE: Not all lines on power poles deliver power. Some are phone or cable lines that lease space. The PUD does not maintain these lines. Noting which type of lines are impacted by a tree or branch helps us gauge the priority of the response. You can upload photos from your phone.
For more information on tree trimming, tree trouble, pruning, planting or any other tree and power line related issue email the PUD: email@example.com or call (360) 385-5800.