A carriageway has been completely removed as part of a five months of bridge replacement works.
Work began along the A1088 Bridge Farm in Stowlangtoft, near Bury St Edmunds, on Monday, July 22.
It is expected the replacement works will take another three months with a completion date of Friday, December 20.
A road closure is in place between the junction with The Street in Stowlangtoft and Sandy Lane in Grimstone End.
The 20 mile diversion takes traffic along the A1088, A14 and A143.
Suffolk Highways shared an update stating the existing carriageway and verge over the bridge has been removed while temporary platforms have been constructed and tested.
A spokesman for the authority said: "Vegetation clearance is complete including the removal of a tree which fell into the waterway.
"Permanent pile foundations have been installed on the northern side of the bridge and works to complete the southern side will be completed this week.
"Thank you to the local community and highway users for their continued patience during these essential safety improvement works."
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