ANCHORAGE, Alaska (AP) - State transportation officials are testing out a new program on Seward Highway aimed at reducing congestion and making it safer for vehicles to pass slow drivers.

The Alaska Department of Transportation has implemented speed limit changes along a 5-mile stretch of the only road leading south out of Anchorage. Drivers in the right lane will have a speed limit of 55 mph, while those in the left lane can go up to 65 mph.

The speed limits took effect Monday and are enforced between miles 60 and 65 of the highway - or Hope Junction to the top of Turnagain Pass.

Officials said making right-lane travelers go slower can help reduce "aggressive behaviors" for drivers looking to pass.

"Passing lanes are less effective when vehicles in the right (slow) lane are traveling near the existing 65 mph speed limit," DOT said in a press release. "Efficient use of passing lanes is critical in summer months when traffic is at its peak and recreational drivers are on the road."

The testing area is a newer section of road and has fewer destinations, DOT spokeswoman Shannon McCarthy said in the release.

She also said engineers are continuing to address problems with congestion on the highway, which averages about 9,000 vehicles each day. Traffic peaks to "20,000 vehicles for several days in July each year."

Allen Bogert and his family were headed south on the road Monday. He told KTUU-TV that he was unsure about the impact of the pilot project.

"People are going to drive how they want to drive," Bogert said. "If someone wants to drive slow in the left lane, they're going to drive slow in the left lane."