POWERGRAMS

22 SAFETY Towering Achievement It would probably be best described as "Mission: Impossible," as in the movie series or, for baby boomers, the 1960s television series. Take a high-voltage transmission tower about to fall into a river due to erosion. Add raging floodwaters that can destroy what it took months to accomplish or bring work to a grinding halt. Mix in the only way to fix the tower is going through the property of another electric utility. That was the mission Alabama Power Transmission Line Services accepted last year. The scene was the bank along a sharp bend of the Tombigbee River near Jackson, adjacent to PowerSouth Energy Cooperative's Lowman Plant. Alabama Power's 160-foot-tall transmission tower was in critical danger of collapsing into the water. Three pier-like "jeies" had been built in 2017 extending like fingers into the river to prevent soil erosion from filling the barge channel in the middle of the river. What that did – at least in Alabama Power's case – was worsen the erosion at the base of the tower caused by "normal" river levels fluctuating. "The bank around our tower was collateral damage" because of the necessary and well- intentioned jeies, said Ma Uhrig, a Transmission Lines Maintenance Support engineer. Making maers worse, major rainfall in early 2018 cut into the riverbank and "exposed roughly half of the structure's foundation," he said. Alabama Power was in a fix. "Losing the tower would not only mean losing a line into PowerSouth's plant next door, but also an APCO industrial customer on the other side of the river in Jackson," Uhrig said. Options were limited. The tower couldn't be moved because the company's right of way had eroded. Buying more land would have taken too long and there was no viable route in the vicinity. Then, a surprise. "We discovered a third party was pumping water out of a swamp on to our job site. It almost cut off our road access to the site and had to be fixed before we could start," Uhrig said. As in the movie and television "Mission: Impossible," it was time for a "Good morning, Mr. Phelps." The plan was to create a new foundation system for the structure. This required installing 133 anchors to stabilize the remaining bank, replacing the lost bank with 700 truckloads of dirt, small stone and larger stone, called "riprap," to stop erosion, and establishing a new environmentally friendly earthen wall. Work began in June, building the bank back 30 feet high, a foot at a time. Work could be done only when river levels were low enough. PROBLEMS WITH ERODING RIVERBANK OVERCOME By Gilbert Nicholson Crews work to stabilize bank around structure crossing the Tombigbee River near Jackson. Uhrig

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