Road closures are in place on State Highway 2 between the Bayfair Roundabout and Te Maunga intersection until Monday morning.
Waka Kotahi NZ Transport Agency is reminding motorists to plan ahead for the road closure, which begun at 10pm on Friday night.
A written statement by NZTA said the closure was required to enable construction of the second of Bay Link's three bridges.
A signposted detour is available via Girven Rd, Maranui St, Sandhurst Dr and the Sandhurst Dr/Mangatawa Interchange.
For high productivity motor vehicles, an alternative detour route is available via Truman Lane, State Highway 29A and either the Takitimu Drive Toll Rd or Cambridge then Moffat Rd.