The "A" in the city name was listing ominously Tuesday afternoon, and crews had roped off an area outside the courthouse to prevent an accident should pedestrians be nearby when the letter falls.
A county spokesman said an employee noticed the "A" was loose during routine maintenance, and others moved to rope off the area below.
The spokesman couldn't say for certain how much the letter weighs. "I can tell you that it requires at 3-inch bolt to secure the letter to the brick building," he said.
Several doors to the courthouse are inaccessible while the danger is present, but county workers hope to have the "A" back upright by Thursday.
The 11-story, $120 million courthouse building in the Durham County Justice Center opened in February 2013. It has 20 courtrooms and also houses the Durham County Sheriff's Office and the Durham County District Attorney's Office.