Raleigh, N.C. — City crews planned to work into the weekend to clean up almost 2.25 million gallons of raw sewage that dumped into a north Raleigh stream, officials said Friday.

Erosion of a stream bank undermined an underground sewer pipe along Triangle Town Boulevard, between Triangle Town Center and Interstate 540, this week.

The broken pipe spilled untreated wastewater into Perry Creek, which flows into the nearby Neuse River.

The city Public Utilities Department learned of the spill by 11 a.m. Wednesday and repaired the pipe by Wednesday night, officials said.

But cleaning up the spill required isolating the sewage and pumping it out of Perry Creek, officials said.

Fresh water was pumped into the stream near the shopping mall Friday afternoon, and crews placed devices downstream to trap the sewage so it could be removed.

Perry Creek south of I-540 was cleaned by Friday night, officials said.

The state Department of Environment and Natural Resources was notified of the overflow, officials said, adding that no environmental damage had been reported.

The city could be cited by state regulators because of the spill.

Last year, a broken sewer pipe at a Cary pumping station dumped about 8 million gallons of raw sewage into Swift Creek. Lake Wheeler and Lake Benson had to be closed for several days because of high bacteria levels related to the spill.