The Woodhill Viaduct in the Irwell Valley goes past the site of the former Higher Woodhill Mill and was last repaired in 1932.
Regular inspections of the structure found no question marks around its safety, according to the Local Democracy Reporting Service.
But the trust found long term repairs were required to allow for the continued level of use of steam and heritage diesel trains.
“There are a great many important Victorian structures along our 12 miles of railway, which thousands of our visitors travel over or under each year, but don’t often see their splendour,” Mr Kelly said.
“Now with this fantastic news, we are able to continue running our award-winning events and services without disruption for future generations to enjoy,” he added.
Meanwhile, James Frith, Labour MP for Bury North, said the award of government cash was a “fantastic Christmas gift for our town”.
“The East Lancashire Railway is a special part of our town’s heritage and culture, and I know everyone in Bury will be pleased that with this funding the future of the railway is secured.”
