Drilling and trenching work for fiber-optic cable installations will continue to affect traffic this week on two key Maui highways, the state Department of Transportation announced.

Contraflow traffic will be in effect on Honoapi'ilani Highway at Ma'alaea from 9 p.m. to 5 a.m. through Friday, with the Lahaina-bound lane from Ma'alaea Road to the Kaheawa wind farm closed during that period, the DOT said.

On Pi'ilani Highway in Kihei, a single northbound lane will be closed from 8:30 a.m. to 3:30 p.m. through Friday.

Meanwhile, in Kahului, trenching work for installation of sewer force mains will cause single lane closures in both directions on Kahului Beach Road from 8:30 a.m. to 3:30 p.m. through Friday.

The DOT is advising motorists to drive cautiously through the work areas and to allow for extra travel time.