A federal project is starting along State Route 89A between Flagstaff and Oak Creek.
The road work will add right-turn and passing lanes and wider shoulders along eight miles between the Vista Point Overlook and JW Powell Boulevard, just south of Flagstaff.
Crews also are flattening side slopes to improve a recovery zone allowing drivers to regain control of vehicles that leave the roadway.
Drivers should expect daytime restrictions on weekdays – and later this month, nighttime closure, as well.
