The NZ Transport Agency will take another stab at closing the Desert Rd, State Highway 1, for a 36-hour period.
The closure is now scheduled for Monday, weather permitting, so a concrete deck can be poured on the Waihohonu Stream Bridge which was damaged in a crash last year.
NZTA Waikato transport systems manager Karen Boyt said a closure scheduled for March 15 was postponed after a problem with the scaffolding was spotted during the final health and safety check.
Earlier planned closures were postponed because of bad weather. Pouring concrete in wet weather can have environmental and safety impacts.
The alternative route is State Highways 46, 47, 4 and 49. The detour is not suitable for vehicles over 46 tonnes, apart from 50MAX which is permitted.