Below is a summary of the closures and how long they will last:Trowbridge - August 16Polebarn Road will be closed in both directions between No.16 Polebarn Road and the junction with McDonogh Court. The closure will be in three phases:Phase 1: Northbound carriageway, from the junction with New Road to the junction with the A363. The alternative routes are:A: Mortimer Street (unaffected section), Frome Road, A361. B: Mortimer Street (unaffected section), Frome Road, A361, A363. C: Mortimer Street (unaffected section), A361, Frome Road, Mortimer Street (unaffected section).