SOUTH FORSYTH -- Right now, a collapsed retaining wall at a south Forsyth shopping center has more questions than answers.
Last week, a portion of a large retaining wall fell at an entrance of the Publix Super Market at The Village at Flynn Crossing at the intersection of McGinnis Ferry Road and Windward Parkway. While the bricks crumbled off the day after a heavy storm, Tim Allen, Forsyth County’s assistant director of engineering, said the collapse was unexpected and that officials are still determining the cause.
“The best anybody can tell at this point is the mechanical connections at the wall where the geogrid was attached to the wall separated,” Allen said. “It was a premature failure; it should have never occurred and there’s no real reason for it. The structural component of the wall is still standing.”
With the structural portion still intact, Allen likened the part that fell to the outside of a home.
“It’s similar to a brick façade, a brick veneer falling off your house; it doesn’t mean the house is going to fall, but the bricks are gone,” he said.
Though the wall is part of a commercial shopping center, Forsyth County is involved since about two-thirds of it is on county right of way, after the property owner donated the land during a traffic signal improvement project done by the city of Alpharetta.
Allen said the wall is being looked at by engineering firm Moreland Altobelli Associates, and the cost and extent of the work will depend on what the frim finds. Once plans are determined, the project will go through the county’s bid process.
The roadway leading to the store has since been closed, but there are other entrances to the shopping center.
The property owner and Forsyth County have both looked at the wall since it was completed in 2002. Allen said the county has received many calls about the wall, particularly in the spring and fall.
“Six or eight months after it was built, it had some internal movement in the blocks that opened up a couple of gaps that had been there since right after it was built,” he said. “We’ve been watching it over the years because the gaps appear to get larger in the spring and the fall when the sun is lowest in the horizon; it looks bigger than it really is.”
The fabric holding the wall has an estimated 75-year lifespan and is being tested, and Allen said the collapse was not typical and that he has spoken with experts who said the collapse was the first of its kind they’d ever seen.
“[The property owner] had an independent evaluation done back in September of ’06 saying there was no problem with it and we’ve done inspections along the way since then,” Allen said. “We had Moreland go down and look at it, and their inspection said it had some movement, but nobody believed the face was going to fall off, because that’s not a typical wall failure issue.”