Motorists traveling on I-95 through Liberty County this week probably have noticed a helicopter hovering low over the salt marsh near the northbound lanes.
Eighty- to 100-foot steel poles necessary to support high-voltage power lines are being installed with an air crane helicopter, according to Jeannine Haynes, public affairs director for Georgia Transmission Corporation.
Haynes said Coastal Electric Cooperative identified the need for a second high-voltage electric-transmission line to connect the Burnt Church Substation in Bryan County with the Tradeport East Industrial Park Substation in Liberty County. She said Georgia Transmission is installing the power line with a helicopter and special equipment like a Hydratek, a multi-purpose, amphibious vehicle.
This equipment allows the power-line project to run through the coastal salt marshes without damaging that pristine environment, she said.
“There is one thing you can’t be sure about,” Haynes said. “Of course, we test the soil to determine how wet it is, but you never can be sure until the poles are vibrated in place. We’ve had no problem installing these poles, though.”
She explained that by law the poles cannot be dug into the salt marsh, which is a protected area. The poles have to be vibrated into the ground with a gigantic hammer that sits atop the foundation pole, driving it slowly into the ground. The foundation pole, a 20,000-pound platform called the power-plant box, and the vibrating hammer each are set in place by the air crane.
When the foundation pole has been hammered to the proper depth, Haynes said the helicopter delivers the rest of the steel pole.
Haynes paused to watch the pilot hover over a foundation pole, slowly lowering the main pole shaft. In short order, the pilot capped the foundation pole with the main pole shaft.
She said concrete poles also are used, but they’re installed into solid ground. Even though the steel poles are installed in a wetlands area, she said they have a lifespan of about 90 years.
Read more in the July 31 edition of the News.