Mr Sarginson said he knew of several families who were up to their fourth generation; his own family's association with Imlay spans three generations.
The New Zealand Refrigerating Company opened its Imlay plant in November 1916, although its official opening did not happen until the following month.
Mr Cadogan said there seemed to be a lot of interest in holding a reunion.
"We had one in 2011 and people there said they were looking forward to the centenary."
He said around 500 people had turned up for that reunion, which was held at Wanganui Racecourse.
The Wanganui Chronicle was unable to contact Imlay management to confirm if an official reunion or event would be held for the centenary.