PHOENIX — Motorists who regularly travel overnight between Phoenix and Payson on State Route 87 are urged to plan ahead or allow extra travel time as the Arizona Department of Transportation moves into the next phase of an improvement project, approximately 7 miles north of Sunflower.

Beginning on Sunday night, Nov. 9, the highway will be restricted in both directions between 8 p.m. and 9 a.m. daily as crews begin slope excavation work. Traffic will be stopped in both directions between mileposts 223-228 and guided through the work zone with the aid of a pilot car.

Overnight traffic restrictions from Sunday night through Friday morning between 8 p.m. and 9 a.m. daily are expected to continue through Nov. 21.

Delays up to 30 minutes at a time are possible. A 12-foot vehicle width restriction will also be in place from mileposts 223-228.

The $6.2 million safety improvement project, which began last month approximately seven miles south of the State Route 188 junction, includes the reconstruction of an existing curve at milepost 227, as well as building a new southbound truck escape ramp at milepost 228. Runaway truck ramps offer an opportunity for out-of-control trucks, which may have inoperable brakes, to safely exit the highway and come to a controlled stop.

The work zone will be clearly marked by temporary barricades and signage. ADOT advises drivers to proceed through the work zone with caution, comply with the reduced speed limit, and be alert for construction equipment and personnel.