The town centre crossing at Jumble Lane was closed all season during the Reds’ previous campaign, but hopes it would reopen in time for their first home match - on August 6 against Cheltenham Town - have ended.
Off-site construction for the bridge began in February, with the estimated completion date set for late summer next year - meaning the likelihood is the closures will affect every Barnsley home game.
Network Rail pledged £2m towards the cost, with the South Yorkshire Mayoral Combined Authority contributing a further £4.8m via their Get Britain Building and Transforming Cities funds, with the remaining cash being put up by the council.
A council statement said: “The temporary bridge will be closed for an hour before kick-off until an hour after the match to support the safety of fans and other users.
“Alternative walking routes include Midland Street, Eldon Street and Schwabisch Gmund Way, or Kendray Street, Mayday Green, Cheapside, Wesley Street, Lambra Road, Pontefract Road and Grove Street.”