The £32m project includes construction of a new road and bridge over the Ely to Peterborough railway line in Whittlesey to replace a level crossing. It is scheduled to open to traffic by December 2022.
Cambridgeshire County Council originally scheduled construction to begin by the end of this year but has now brought it forward.
Work has begun on the earthworks which involves bringing in materials to construct the embankment that the new road will be built on and it will continue throughout the summer. The main site compound will be built next month; later this year the focus will be on the structure for the underpass and bridge.
Jones Bros managing director John Dielhof said: “The start of this project is an exciting milestone, particularly for the local residents and commuters who will benefit most when the development is completed. We look forward to delivering the King’s Dyke transport scheme on schedule and on budget.”
Cambridgeshire County Council leader Cllr Steve Count said: “I am thrilled that we are starting work on this vitally important project for the area and five months earlier than planned is a great achievement.”
There will be a two-week road closure on the A605 put in place by Lindum Homes. During this time, Jones Bros will be taking the opportunity to carry out underground utility works to minimise disruption to the public.