She said it would affect all industries from farming to retail.
"I think it will have a positive impact economically for our region," she said.
"It's a great opportunity for businesses in the Wairarapa and Pahiatua."
Ms Gundersen-Reid said although it would be likely that new people would move into the region, it would be up to the towns to promote themselves as a great place to live.
Federated Farmers Wairarapa dairy chair Chris Engel said the project was a great move for the region and the industry.
However, he expected it would not have a direct effect on Wairarapa dairy farmers.
The project involves a new drier at the Pahiatua plant, which would produce up to 85,000 metric tonnes of milk powder.
"If it can be made locally, it's got to be good for the region and everyone," said Mr Engel.
Tararua Mayor Roly Ellis previously told the Times-Age his council was willing to work with Fonterra through the consent process. "It's extremely good news for Pahiatua and we like to think, with the number of jobs, people would want to move into the area," he said.