New restrictions are now in place between the eastbound A690 and New Elvet Bridge as a £2.5m scheme is carried out.
Durham County Council said the work is due to last six weeks, four weeks fewer than originally anticipated.
It is the last in a series of traffic works being carried out in Durham.
People travelling eastbound on the A690 will not be able to turn right onto New Elvet Bridge after crossing Milburngate Bridge - instead being diverted up and round Gilesgate roundabout.
Those approaching Leazes Bowl roundabout from New Elvet Bridge will not be able to turn right towards Gilesgate roundabout and those motorists affected are urged to use an alternative route.
The existing right turn ban at the New Elvet traffic lights onto Old Elvet will be temporality suspended.
Several bus services will be using different routes and passengers are advised to check with their operator.
The works are the last phase before the resurfacing of the area, which will complete the major works needed for the scheme.
Adrian White, head of transport and contract services, said: \"We're extremely grateful to everyone for their continued patience while we carry out these vital improvements, which promise easier journeys in the future.
\"We've now reached the most disruptive part of the works but, by constantly revising and adapting our approach to help the public, we've been able to reduce this stage by a month.\"