Cambridgeshire County Council has awarded the estimated £35 million Ely Southern Bypass contract to VolkerFitzpatrick.
The 1.7m single carriageway that includes a viaduct crossing and bridge over the railway line.
The A142 is a trouble spot currently for long queues of traffic but the new road way between the A142 Stuntney Causeway and A142 Angel Drove is expected to release those pressures.
Work is expected to begin at the beginning of 2017 and will take around 2 years to complete.
The bridge will also be home to new walkway that faces Ely and will give new views of Ely plus improved access to the Great Ouse Wildlife site.