by Paul Hull

Right-of-Way Maintenance is Always a Top Priority

Few people understand how much time and effort are required to establish the right-of-way (ROW) for a utility. Negotiations with property owners are not always easy, and some of the very people being served have objections. It is sensible, then, to maintain every ROW and keep it free from natural threats as it is protected from other intruders.

Many miles of ROW maintenance involve stretches of countryside where nature's growth continues in all weathers.

Hurricanes in the South, fires in the West, and ice storms in the North are not the only events that can harm power lines. Whatever the weather is like in an area, nature keeps going and growing. Even after the wildest, most destructive storms, the trees and shrubs recover and start to mend their wounds. It is this natural, continual growth that is probably the greatest threat to power lines–not so much the huge tree trunk falling and breaking a pole as the steady growing of twigs and branches until they find a disruptive home on and around the poles. As the growth occurs on a seasonal basis in most locations, so should a scheduled utility plan to control it. Florida Power & Light (FPL), a large utility located in a growing climate, completed its three-year cycle of clearing vegetation from main power lines (feeders) in 2008, and completed the second year of its approved schedule to implement a six-year cycle for neighborhood power lines (laterals). This means that, after two years, FPL is on the planned schedule for achieving its six year average lateral trim cycle in about three years. In 2008, FPL trimmed trees and cleared vegetation from more than 11,000 miles of power lines, which helped prevent customer outages. Planning a ROW maintenance program seems to be a practical and efficient start for any utility, just as it is for all equipment and vehicles.

Crews and Control

Trees are the most likely intruders for aboveground power and telecommunication lines. The poles that carry the power are above us, just like trees. Poles, however, stay basically the same size, while trees continue to grow and spread in all directions. Trees provide many benefits for a community, including taking dust and other pollutants from the air and, through their root systems, playing an important role in soil conservation, flood control, and erosion control. "The protection of trees is not only desirable but essential to the health, safety and welfare of our citizens, present and future," is how one county engineer described the situation. That does NOT mean trimming trees to provide good clearance to power and telecommunication lines is wrong or ill-advised. It does mean that all ROW maintenance should be planned to give the best results for everybody, and that isn't so difficult. "Everybody" is the community, which comprises the utility and its customers.

This cutterhead on an excavator is an efficient stump grinder.

My personal experience with ROW clearance is provided by the tall cottonwoods that are at the corner of my office garden and the alley that runs behind it. About every three years there are spreading cottonwood branches that need pruning to give the power line some freedom. That is how most customers in urban areas see ROW maintenance. A single tree near their home or office is trimmed occasionally. What few of us notice are the miles and miles of power lines that cross the country, linking one community with another. In some counties, the power lines seem to go through virtual forests, so the ROW maintenance for these lines can be a continuous, busy cycle. For my cottonwood, the local utility sends a crew that trims it, along with similar trees in the neighborhoods. For the maintenance of lines in the more rural zones of a utility's service area, it is quite usual for independent, professional tree services to do the work.

Some people are surprised how big a tree a chipper can handle efficiently.

Is there a rule for using in-house workers or outsourced professionals for your ROW maintenance? Probably not. But watch the difference in the way they work. You will find that your own personnel, for whom tree trimming would be a break from their usual routine, are less professional unless they have been well trained for tree and brushwood management. Workers who are used to aerial trucks have few problems going up to cut branches, but tree trimmers for whom this maintenance work is their bread and butter seem to know more about trees and approach such challenges as falling, lopped branches with more confidence. They are as familiar with chain saws as other tools to linemen. The professional tree cutter's attitude toward safety is as serious and efficient as the lineman's attitude toward safety up the power pole. This is just my experience, and not a criticism of any company; I have noticed that two professional tree trimmers can work faster, more cleanly and more safely than a crew of four or five workers who are not used to trimming trees.

Having the right equipment and knowing how to use it are essential qualifications for all those who would trim trees; the branches and brushwood also need to be disposed of after the clearance of the ROW. Lewis Tree Service is one of the most successful companies in the United States for providing comprehensive vegetation management services for utilities. Lewis Tree Service believes in and enforces a code of safety rules for its professional employees. Their rules include items such as walking around a vehicle or piece of equipment before moving it, using the required safety barriers and safety equipment to define the work area, having a full body harness in proper use when working on an aerial device, never handling a chain saw with one hand (either on the ground or aloft), respecting the drop zones and prescribed felling zones, using chaps whenever saw operators are cutting on the ground, not wearing a full body harness while operating a chipper, and maintaining the minimum approach distance at all times.

Equipment for ROW Maintenance

Let's not forget the lower end of ROW clearing. Trimming branches to prevent interference or damage to the high transmission and distribution wires has everybody looking up, but there's plenty of clearing to be done on the ground along the ROW. There must be good access for utility workers when repairs or updates are needed. "One project we had called for the clearing of a power line ROW that was a little over nine miles long and 60 feet wide, mostly Ponderosa Pine," observed Bob Baker of Baker Timber Products. The tract he described was for Black Hills Power & Light and it starts in Lead, South Dakota and goes through the Black Hills to Nemo, also in Lawrence County, South Dakota. In addition to the hilly terrain, the tract covered what Baker described as "sensitive ground."

"We bid the project assuming it would be a typical three-man crew with our feller bunchers and skidders," recalled Baker. "Due a scheduling problem, that equipment was tied up. So we started the project with a Fecon FTX. I figured we'd put a one-man crew on the project to start with and pull the heavier equipment in when we were pushing the deadline." He was surprised, most pleasantly, by the progress of the FTX, which is a compact, tracked machine that can be fit with multiple attachments powered by the loader's hydraulics. For this ROW work, Baker used a 14" bunching shear and a Bull-Hog grinder. Anything over 12" was cut with a chain saw, with the timber laid down parallel to the power lines. About 90% of the trees to be cleared were handled with the bunching shear. After these steps, the same operator came in with the Bull-Hog grinder and mulched the remaining materials as well as the logging and clearing slash.

Not all ROW maintenance is done in sunny, green conditions. Make sure your equipment can work in all seasons.

Baker credited several factors for the success of this ROW project. The highly maneuverable FTX could place the sheared trees accurately and quickly the first time. No second or third passes were needed to get it right. For cleanup, the Bull-Hog quickly handled the underbrush, mulching the slash and grinding stumps to ground level or below. Switching between attachments was a quick task for the operator. What was expected to be a 30-day project with a three-person crew (plus heavy equipment) was completed by one person on a much smaller FTX in 17 days.

Among other equipment that could be ideal for ROW maintenance are the attachments from Shinn Cutter. They can deal with trees of any size, and attachments such as the SC-95 can attach to an excavator and even reach those awkward parts of a ROW–such as steep banks or marshy areas that other equipment can't. Shinn Cutter also makes stump grinders, attachments that can be exchanged with a cutter head in about 45 minutes to clear the ROW quickly and efficiently. The TimberAx from Loftness offers a reverse rotation design that will lift material off the ground (rather than pushing it downward) for better results and has been used successfully for cutting and mulching material up to 6" in diameter with as little as 38 hydraulic horsepower. It cuts and mulches unwanted trees or brush, including vines or grass, all with the same knives. For these attachments, it is important to check the flow and pressure of the power unit so the right cutting model is acquired.

The telescopic boom on the Tree Trimmer from Jarraff Industries can extend up to 75' with a 90-degree range of motion–enough to handle almost any tree in your ROW. The 24" blade on the end operates at 3,200 rpm. Sensibly, there is a limb deflector that protects the operator from falling branches while perfect maneuverability is achieved with the hydraulically powered turntable (which has a 360-degree range of motion and 40 degrees of lateral tilt). Jarraff provides either a wheeled or tracked version of this ROW maintenance equipment.

Disposal of Cut Trees and Brushwood

Disposing of the cut branches and brushwood is part of ROW maintenance. Local regulations and custom will dictate the best disposal method for many projects. Again, there is excellent equipment available to complete the work quickly, safely and profitably. Bandit Industries offer a broad rage of disc- and drum-style chippers with capacities from 10" to 21", and all of them offer the invaluable reversing feed that quickly helps you if anything becomes stuck. Among the Bandit equipment are hand-fed track chippers and wheeled chippers, stump grinders (11 models available), whole tree chippers, horizontal grinders, PTO drive chippers, and even a mulch coloring system (the Color Critter II), which offers some interesting and practical results when working with brushwood and trees.

Atlas Tree, based in Santa Rosa, California, had a two-year contract with a northern California power company. "There are existing power lines, cross country lines, that have higher voltage and feed the smaller lines," observed Rich Kingsborough for Atlas Tree. "We're going over steep hills and back country to reach them and the terrain is rocky and difficult to navigate. Sometimes the crew may be 10 miles from the nearest paved road and they have to rely on forest roads (not always well marked)." You can become lost for hours if you make a wrong turn. Add environmental issues to the difficult terrain–there are wetlands, creek crossings, or areas containing endangered or protected vegetation. Before beginning ROW clearance, crew members tagged the protected bushes and trees so they wouldn't be trimmed or removed.

In town, this kind of chipper could be the most practical.

Doing the job well was due to the decision to use track-mounted equipment. "We decided to use a Vermeer BC1499TX brush chipper. There was nothing else that offered a low enough impact on that terrain," said Kingsborough. "Some other track-mounted chippers are much heavier and need a lot more room to maneuver. They would have caused too much damage." Most of what was chipped was large, woody bushes, along with several small oak trees, opine and fir trees. Manzanita bushes presented their own special problems. Found in the western United States and northern Mexico, these bushes are low-lying, with crooked trunks and hard wood. The Vermeer equipment, however, coped very well. Specifications for the ROW maintenance job called for at least 35'of safe clearance around the power lines; Atlas Tree provided about 50' of clearance. "Our customer was very happy with our progress," said Kingsborough. "The scope of what our crews did in such a short time was amazing. A lot of it was solid brush and you couldn't even walk through it. Now it looks like a park."

Having employees work around the danger of high-voltage lines requires education, and Atlas Tree employees go through the Electrical Hazard Awareness Program (EHAP), sponsored by the Tree Care Industry Association. "They may already be a veteran tree climber, but this course educates them on the dangers of working around high-power lines," commented Kingsborough. Started as a one-man operation with a chainsaw and pickup truck, Atlas Tree now offers a complete tree service and has 50 employees. It is a very good example of the professional skills and attitudes that can make ROW maintenance a quick and safe task. Whether doing ROW maintenance with in-house or outside personnel, protect the utilities' reputation by making sure it is all done well.

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