The smell from Affco's Imlay works was so bad on Thursday that Amrit and Johanne Patel had to close the windows of their Heads Rd house.
They said it was similar to the smell from Wanganui's notorious wastewater treatment plant last summer, and were not sure whether it came from there or the meatworks.
They had visitors from Australia, who also couldn't believe it. "It really stunk ... just about all day," Mr Patel said.
And yesterday evening the awful smell was back in the Heads Rd area.
"It's enough to make you gag," said one Chronicle reader.