"There was a bunch of them up on No2 field, then others by the other side of the clubrooms.
"Fortunately it's not on the main playing area."
Tauranga City Council spokesman Marcel Currin confirmed 20 portable toilets were pushed over at Blake Park - a line of six loos at one end of the park and 14 at the other end.
Mr Currin said the tipping over of the loos was being treated as vandalism.
Contractors were yesterday cleaning up and disinfecting the affected grass areas. Meanwhile, it was hoped forecast rain would help dilute the mess.
Mr Currin said the spillage was contained on the grass with no run-off into waterways as there were no stormwater grates nearby.
Neither contaminated area was on any of the park's sportsfields.
However, they had been roped off as a precaution.
"We're told health concerns are pretty minimal once everything's been cleaned up so the area won't be closed off," Mr Currin said.
When asked about potential health risks from the sewage spill, Toi Te Ora Public Health Service medical officer of health Dr Jim Miller said: "We are aware that there has been a sewage spill at the park and that it has been cleaned and disinfected and Tauranga City Council environmental health are inspecting it."
Tiki Taane, who performed and hosted Xmas in the Park, said organisers had worked hard to make the event a positive success. "It would be a shame that these port-a-loos would overshadow such a great event," he said.
"It's a shame that kind of thing happens at all."
Xmas in the Park was a family event designed to help raise money for Kea Charitable Trust through gold coin donations.
Paul Salmon of Transpacific Technical Services, which donated the toilets, said he was unable to comment yesterday.
