Vegetation Management
Keeping your electric service reliable
Our customers want reliable power – in good weather and bad. Trees are generally the most common cause of power outages, and vegetation management is critical to keeping the electric power grid reliable.
To make sure our customers have reliable electric service, PPL Electric Utilities has developed a comprehensive program to manage vegetation around power lines. We maintain about 35,000 miles of transmission and distribution lines. Keeping trees and other vegetation away from these lines is very important.
Why do we trim trees?
Trees are generally the most common cause of power outages. We work very hard to keep them away from power lines so you will have reliable electric service. We spend millions of dollars each year as an investment in safe, reliable operation of the electric delivery system.
Transmission lines deliver large amounts of power from power plants to local communities. Transmission lines are vital to our region and to our nation's security and economic well-being. It is imperative that trees are kept clear of these transmission lines.
Tree contact with higher-voltage lines can result in widespread power outages to many thousands of homes and businesses. Because these lines are so vital to deliver electricity, we clear trees and other vegetation beneath or near transmission lines.
Distribution lines typically run down local streets and highways to deliver electricity to customers. We generally prune or trim trees away from these lines every few years. Tree trimming varies based on the type of facilities, tree species and density, growth rates, proximity of the trees to the power lines, and recent power outages on the line.
Federal and state requirements – Vegetation management is required to meet federal and state reliability standards.
After the 2003 Northeast blackout, federal standards mandated that utilities have a vegetation management program to prevent widespread outages on the transmission system.
The North American Electric Reliability Corporation strictly enforces the standards. Utility companies who fail to comply with the standards can be fined up to $1 million per day for each violation.
The Pennsylvania Public Utility Commission also requires PPL Electric Utilities to adequately maintain its facilities to provide safe, reliable electric service to customers. Service reliability is monitored each year to ensure that we meet our state obligations.
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How do we trim trees?
PPL Electric Utilities' professional foresters work directly with qualified line clearance tree trimming companies, who are trained to safely work around energized power lines and perform the work properly.
On the distribution system that delivers power to your neighborhood, our contractors use a technique known as directional pruning, which is widely accepted in the industry as the best practice. This technique removes only those branches growing toward the power lines. With directional pruning, entire branches under, over or beside power lines will be pruned back to the main stem of the tree or to another large branch.
Remaining branches are left to grow naturally, providing more of the tree's natural shape. By only removing those braches that are growing toward the power lines, less stress is placed on each tree. The Arbor Day Foundation strongly endorses directional pruning techniques as being better for tree health. This method of pruning also follows the nationally recognized Standards for Tree Care Operations.
We look to make the fewest cuts possible to clear tree limbs from the power lines. Some customers may want an arborist or landscaper to perform additional pruning for aesthetic purposes since the utility trims mainly for safety and reliability.
On the transmission system, which is like a highway for electricity, we take a more proactive approach toward maintaining utility rights of way where transmission lines are located. In the past we selectively trimmed to keep tall-growing trees away from the lines.
Now in most cases all vegetation under these critical transmission lines is cleared. Tree species that may in the past have been allowed in certain locations now must be cleared.
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Why has PPL Electric Utilities changed its approach on transmission line vegetation maintenance?
After the Northeast blackout in 2003, the federal government adopted strict new reliability standards for electric utilities because a tree was the primary cause of the blackout.
The reliability standards assumed a "zero tolerance" policy when it comes to tree-related power outages on transmission lines since they can leave large areas without power.
Additionally, the federal government can impose stiff financial penalties if utilities fail to comply. Under the new standards, certain clearances must be maintained between the overhead lines and any vegetation.
The clearances recognize that lines can sag under heavier loads and trees can sway in the wind. Subsequently, PPL Electric Utilities and companies across the U.S. began taking a more proactive approach to ensure that we meet these higher expectations to maintain the reliability of the electric grid.
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What is "Wire Zone/Border Zone"?
Our vegetation management program is responsible for reliability of 4,500 miles of transmission power lines. On certain rights of way, PPL Electric Utilities now uses industry best practices, known as "Wire Zone-Border Zone." The new approach, which now applies to transmission lines of 115 kilovolts and higher, means most trees and shrubs that we have allowed to remain directly under the lines in the past are no longer are permitted.
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The Wire Zone is considered the area directly under the transmission lines and extending out 10 feet. Trees are typically removed from the wire zone as they are incompatible with high-voltage wires. Over time, low-growing grasses and other species native to the area will be permitted to grow back.
The Border Zone extends from the edge of the wire zone to the edge of the PPL Electric Utilities right of way. Small trees and certain shrubs will be allowed to grow back over time if they do not pose a reliability risk. According to Audubon Pennsylvania, border zones can become and remain early successional scrubland (scrub-shrub), a habitat that is important to several bird species of conservation concern in Pennsylvania and other parts of the northeast.
The Danger Tree Zone is located outside of the utility right of way. Because some trees could pose a risk of falling onto transmission lines, our right-of-way agreements allow us to remove any tree from this area. |
We will perform only the work that we believe is necessary to meet reliability standards and keep electric service reliable.
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Helicopter patrols improve reliability
PPL Electric Utilities uses high-tech solutions to ensure we maintain compliance with the federal reliability standards. A technology called LIDAR (Light Detection and Ranging) makes the task of monitoring potential tree interference with transmission lines faster and more accurate.
The technology uses laser beams from a helicopter to accurately measure distances from a wire to any potential obstructions including trees. It creates a map that displays the relative heights and positions of towers, power lines, and trees. LIDAR inspections each year verify clearances around high voltage transmission lines and help us prioritize where clearance work is needed to meet the reliability standards.
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What is integrated vegetation management?
PPL Electric Utilities is proud to be a Tree Line USA® award recipient from the National Arbor Day Foundation. The Arbor Day Foundation, in cooperation with the National Association of State Foresters, promotes the dual goals of safe, reliable electric service and abundant, healthy trees across utility service areas.
The program seeks to promote best practices in utility arboriculture and public education through five core standards: annual worker training, quality tree care, tree planting and public education, energy conservation, and collaboration with community groups.
Ongoing and well-documented research has shown that integrated vegetation management programs that use herbicides provide significant wildlife benefits to reptiles, amphibians, song birds and mammals by increasing habitat diversity.
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Cleanup and wood chips
PPL Electric Utilities does not remove or dispose of any vegetation from transmission rights of way after cutting. One reason is that materials belong to the property owner. Also, in some areas, like hillsides, leaving cut vegetation can protect against erosion. When work is done on local distribution facilities, tree crews typically chip and remove smaller limbs and branches.
Larger wood is generally cut into handling lengths and left at the base of the tree for property owner use. In more rural areas where possible, tree crews will pile pruning debris to create cover for wildlife. Larger limb wood will be separated and left for property owner use.
If you'd like wood chips, please see the foreman of the tree crew doing the work. The foreman will do his or her best to grant your request. If you do request chips, be mindful that contractors will deliver full loads – 5 to 7 cubic yards – and will not remove unused chips once delivered.
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Why do we use herbicides?
PPL Electric Utilities uses herbicides to effectively manage vegetation conditions along our power lines. Research has shown that herbicide use on rights of way can greatly enhance wildlife habitat diversity, while promoting low-growing plant communities.
By promoting low-growing plant communities and increased habitat for wildlife that feed on many of the undesirable vegetation species, less herbicide use will be required to ensure safe and reliable electric service.
We are committed to managing vegetation in ways that will have a minimal impact on our environment. We will only apply herbicide products that have been approved for use on utility rights of way by the U.S. Environmental Protection Agency. These products have undergone significant testing. In fact, some of the materials our contractors will use are the same as those commonly used by homeowners.
All herbicides used on our right of way are applied by state certified applicators. Within the rights of way, vegetation that is acceptable is generally left untreated, while vegetation that has potential to grow too close to power lines is treated. Herbicides provide the most effective means to reducing re-sprouting by effectively treating the entire plant system.
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Don't try to prune or remove trees around live wires
Do not attempt to prune or remove trees near power lines. Contact with a power line can cause serious injury or death. Electricity can "flash over" if someone comes too close to a high-voltage line.
Our qualified line clearance tree trimmers have specialized training to work around our power lines. If you or a private arborist working for you plans to remove a tree growing within 10 feet of a power line wire, call PPL Electric Utilities. We will have one of our tree trimmers prune the tree to provide a safe working distance.
We do not prune or remove trees around the service wire between your house and the utility pole. We will be happy to de-energize your service wire and lower it to the ground so you can do the work safely. Both of these services are provided at no cost. We do require at least three business days' notice, and additional time may be required to schedule a crew. Please call 1-800-342-5775.
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Our commitment to you
Our easements grant PPL Electric Utilities the right to operate and maintain electric facilities on property owned by others. We will do our best to notify residents or property owners in advance of any vegetation management work. We want our customers to understand what line clearance work PPL Electric Utilities must perform, the reasons for the work and the timing.
If you have any questions about our approach, you can call our vegetation management hotline at 1-877-528-2889 or email us at PPLVegetationManagement@pplweb.com.
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Planting near power lines
Transmission line corridors can be cultivated with native grasses that can be visually appealing, provide food to birds and wildlife, and are more compatible with high-voltage power lines.
If you plan to plant a new tree, or replace an existing tree, please pay close attention to what type of tree you plant and where. When choosing a spot to plant your tree, make sure it will have plenty of room to grow to full maturity.
Speak with the nursery where you plan to purchase the tree and tell them about any power lines so they can help you select the right tree. Selecting the right tree for the right place will make your property safer, more attractive and reduce the likelihood for power outages.
PPL Electric Utilities' professional foresters can also advise you to select the proper tree for the location you have chosen. For more information, call our vegetation management hotline at 1-877-528-2889 or email us at PPLVegetationManagement@pplweb.com.
Learn more about planting the right tree in the right place.
Compatible species
Tree care tips
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For more information
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