Hartsfield-Jackson International Airport’s road construction project is entering its final phase Thursday, with another road detour affecting some travelers.

Travelers headed to Hartsfield-Jackson from downtown, Camp Creek Parkway, Riverdale Road or I-85 northbound will not be affected by the new detours. But airport officials said drivers should obey the 25 mph speed limit and allow extra time to get to the airport.

As of March 19, motorists leaving the rental car center will take a detour to I-85 and will not have access to Riverdale Road southbound. Those leaving the domestic terminal and headed to Riverdale Road will take I-85 South to the Riverdale Road exit. At the rental car center, the airport is permanently closing a short section of road called Jet Road and opening the Rental Car Center Parkway Connector.

The road project started in 2012 and was intended to take two years to complete. But the $60 million roadway redesign, which is intended to allow more time for decision making and reduce traffic weaving and yielding, was not completed at the end of 2014 as originally planned and is entering the final phase now.