The incident is directly across from Te Kura O Matapihi.
Principal Tui Rolleston said she was first alerted to it about 8pm last night.
Her daughter arrived home from netball and said there was a bad smell and wet ground near the kura.
"She said oh my god it stinks!"
Rolleston said she called the council to alert them. When she arrived for work the incident had been contained to the side of the road opposite the school.
She said the council assured her there was no health or safety risk to the students.
While it was the first leak since the pipeline became operational, it was not the first issue.
A vent opposite the school regularly expelled a "foul odour", she said
Teachers with classrooms on that side of the school complained and the school kept students off the fields when it was bad.
Garry Holloway, a Matapihi resident who acts as a liasion between the community and the council regarding the pipeline, said the odour issues had been a problem up until about a month ago.
The cause of the leak was an air release valve that failed near the odour green dome.
He said repairs were completed at 9.30am and the pipeline is fully functional again using another air valve. Staff were now checking all air valves along the pipeline again.
"Council contractors were onsite throughout the night to ensure the leak was contained. Including a sucker truck in case of any further leaks. Contractors have cleaned and disinfected the area," Johansson said.
"Council staff have been keeping the community informed. We have apologised to the community and thanked our contractors who worked through the night and are still on site this morning."
The council did not confirm how much sewage had leaked so far, nor did it say whether residents were asked to leave their properties.
The pipeline project was completed earlier this year, and Tauranga City Council held a celebration of the $107m, 15-year project just last month.