CONCORD, N.H. — A pedestrian survived a 15-foot plunge down a storm drain and was rescued by the Concord Fire Department, officials said.

Firefighters were told that the cover for the storm drain was off and that the pedestrian unwittingly stepped into the hole Wednesday morning near the Steeplegate Mall.

“He did not see the storm drain and fell in,” Fire Chief Sean Brown  told the Concord Monitor. The victim was reported to be unhurt.

It was unclear why the storm drain was uncovered.

“It was a typical storm drain — the kind that people drop their keys down into, which is [a] more common thing than people falling into them,” Brown said.

Fire crews had to check to make sure there were no dangerous sewer gases before rescuing the man. The victim, whose name was not released, declined medical treatment.