CARY, N.C. (WNCN) — Nearly 4,000 gallons of sewage spilled into a waterway that flows into Camp Branch, officials say.

Town of Cary officials said Thursday that the spill went on for roughly 90 minutes Wednesday near 8921 Holly Springs Road.

It was caused by a piece of concrete construction debris that lodged in the sewer line, causing 3,759 gallons to spill. 

About 1,600 gallons backed up in a depression near the manhole that spilled was pumped back into the sewer system for disposal and treatment, officials said.

The ground was cleaned by flushing it with water. Officials say about 80 small fish were affected.