Part of A143 from Haverhill to Bury St Edmunds to close for 12 days with 40-mile diversion for drivers
The A143 will be closed just outside Haverhill for 12 days to allow for the new roundabout at the access to the Boyton Place development to be linked to the main road - with a 40-mile diversion route in place.
As part of the 1,100 home development now in the process of being constructed by Persimmon Homes, the roundabout has been built opposite the derelict Fox pub to give access to the new estate.
It will also provide access to the new relief road that will go around Haverhill and link up with Withersfield Road on the Cambridge side of town.
The next phase of construction of the relief road will commence this year.
Traffic lights will be in operation from March 8 to 30 to allow Persimmon to build the new road from the roundabout into the existing Bury St Edmunds bound lane.
A statement from Persimmon said: "On March 30 we need to close the road until April 11 to allow the remainder of the new road to be built.
"We have worked closely with Suffolk County Council Highways team to programme these works and endeavoured to minimise the length of time the road is closed and we apologise in advance for any disruption that this will cause.
"The signed diversion route for the road closure will be A1017 to Baythorne End, A1092 to Long Melford, A134 to Bury St Edmunds, A1302 through Bury St Edmunds, then A143 back to Haverhill. With the same route then signed in reverse."
The proposed diversion route is legally required to replicate the class of road that is being closed, in this case an A road.
If followed, it would result in a distance of almost 40 miles.
As worked out by using the AA route planner website, however, an alternative diversion that would take drivers to the A143 junction with the B1061, going via Haverhill and Kedington, would amount to about 5 miles.