Emergency crews were called to the Delaware Water Treatment Plant on Thursday morning on a report of a fall.
A man, who authorities said was doing construction at the plant, was reported to be injured in the fall which occurred around 11:15 a.m.
The incident occurred at 3080 U.S. Route 23.
A city spokesman said the man fell around 15 feet. He is employed by Shook Construction out of Dayton.
A medical helicopter transported the man to Grant Medical Center in unknown condition.
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