Inaccessible.
Most people involved with the recently completed $306 million Wyoming-Jacksons Ferry Line, a 765-kV transmission line in the Appalachian Mountains, readily agree that this word describes the high-elevation project.
The project extends more than 90 mi. (145 km) through the mountains from Wyoming County, WV, to Jacksons Ferry, VA, with 11 mi. (18 km) passing through the Jefferson National Forest in western Virginia. Along this path, workers installed 3,420 mi. (5,500 km) of wire for 333 towers.
American Electric Power Co. (AEP), the owner and designer of the new line based in Columbus, OH, acted as the general contractor on the project. In addition, there were three primary contractors with specific roles on the project. The primary contractors were hired, according to Todd Burns, AEP’s corporate communications manager, so they could “focus on their areas of specialty.”
PAR Electrical Contractors Inc., part of Quanta Services Inc., served as the line construction contractor and also participated in construction preplanning. PAR is based in Kansas City, MO, but its project headquarters was in Bluefield, WV. Phillips and Jordan Inc., based in Wilmington, NC, performed right-of-way services and tower site clearing. Saint Albans, WV-based Central Contracting Inc. received the contract for access road construction, reclamation and restoration.
In 18 months, Central Contracting built 160 mi. (257 km) of access roads to the 333 tower sites in the mountains. The company also handled all of the permitting, environmental design and erosion control features for the access roads. It also provided maintenance for the roads and restored them to their natural state. Furthermore, the contractor installed 6 mi. (9.6 km) of roadway drainage.
In all, 2,000 acres (800 ha) had to be cleared of trees and dirt and then reseeded during restoration. Central Contracting used two Komatsu excavators, a PC200 and PC300, and two Komatsu dozers, a D61 and a D65. Additionally, the company used a Caterpillar 725 articulated truck during the project. Some of the access roads were dirt while others were made with stone. Roughly 150,000 tons (136,000 t) of road stone were used.
Steve Cvechko, president of Central Contracting, was amazed at the “sheer size of the project” and said one of the challenges of the project is that the work zone was “really inaccessible.” Crews would drive as long as an hour in four-wheel drive trucks to go from “black top to the work site,” said Cvechko. “It was so inaccessible, specific areas were designated as landing zones for helicopters in case someone got hurt.”
Other challenging aspects of the project include working in an environmentally-sensitive area and accommodating environmental regulations. The Indiana bat, an endangered species, and its habitat could not be harmed during construction. During summer months, workers were prohibited from clearing trees near the habitat for approximately 225 Indiana bats. When a bat was found, the entire operation in a 5 mi. radius was shut down for the summer.
“One section of the line we couldn’t work in from May to September because of the Indiana bat,” Cvechko said.
Special care was also taken not to impact any streams in the work zone.
Get to the Chopper
Helicopters were used on this project because of the obvious high elevations, but they were also needed to reduce the construction disturbances on the environment as well as limiting the number of access roads that needed building. Working for PAR Electric, the Oregon-based Columbia Helicopters assisted with many tasks during the project.
Columbia sent a Boeing 234 Chinook helicopter to help set towers and bridges/cross arms. The Chinook set the bridges onto the tower legs approximately 90 ft. (27 m) above the ground at two sites because crews were unable to get cranes to the site. One transmission tower bridge weighed 21,000 lbs. (9,500 kg). In addition, the Chinook was used for pre-staging other bridges and pre-staging 106 spools of cable. A Vertol N192CH was sent later to transport steel to various pad sites and to set arms, which weighed approximately 6,000 lbs. (2,700 kg) each, onto some of the towers.
For the sites accessible by crane, PAR rented cranes from Lynchburg Crane Service Inc., located in Lynchburg and Roanoke, VA. The cranes were primarily used to erect towers. PAR used a 200-person work force, consisting of its own crews and local labor, on this project.
Steel Replaces Aluminum
The 75-kV transmission line project replaces the existing four-wire bundle measuring 18 in. (46 cm) per side with a new six-wire bundle held in place by a 30-in. (67 cm) diameter spacer-damper. Additionally, the existing guyed-V aluminum and self-supporting four-legged steel towers were replaced with galvanized steel guyed-V towers because of the high cost of aluminum and market factors. Also for environmental reasons, AEP used the galvanized darkened, non-reflective steel so that the towers would blend into the surroundings.
A 1,000 ft. (305 m) wide corridor was recommended by a team of experts to reduce the environmental impact and to try to preserve the natural landscape’s scenery. This corridor includes a 200 ft. (61 m) wide right-of-way.
The new line was built to support increased demand for electric power and to improve the reliability of services. “Energy demands in this region have increased over 161 percent since 1973,” AEP’s Burns said.
After two and a half years of construction, a dedication ceremony was held May 8 to celebrate the completion of this first electric power transmission line in the United States to use a six-wire bundled conductor. The benefits of this new line include the reduction of electric and magnetic fields surrounding the high-power transmission line and the reduction of noise levels by half.
“It has been an incredible project,” said Burns, “particularly in the higher elevations.”
Electricity was expected to start flowing through the new lines this month. CEG
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