Construction began on the northeast ring road in 2007. This shot looks southeast at work on Deerfoot Trail this summer. (Northeast Stoney Trail Group)

The northern part of Calgary's ring road opened to traffic on Monday afternoon, giving drivers access to a 44-kilometre stretch that includes 12 interchanges.

The full section spans from Highway 1 (16th Avenue N.W.) on the west side of the city to Highway 1A (17th Avenue S.E.) on the east side. That means motorists can now drive on Stoney Trail from Harvest Hills Boulevard to 17th Avenue S.E.

About 30,000 to 40,000 vehicles per day are expected to use Stoney Trail.

"The residents of north Calgary will enjoy a great benefit as a result of this portion of the ring road, not to mention the huge impact it will provide our transportation and logistics industries in moving their products more quickly and efficiently," Mayor Dave Bronconnier said in a news release.

Officials drove through a banner to officially open the north leg of Calgary's ring road. (CBC)

Construction of Stoney Trail was split into two projects. The northwest section between Highway 1 and Deerfoot Trail was done under a conventional setup where a company won a bid to design and build the road, which will be maintained by the province.

The province paid $385 million, and the federal government covered $75 million of the northwest section.

A public-private partnership began building the northeast portion, which includes the part between Deerfoot Trail and 17th Avenue S.E., in 2007. Under the $650-million agreement, the Northeast Stoney Trail Group will maintain the road for 30 years.

Monday's opening of the northern leg means Calgary's ring road is about 45 per cent complete.

The province reminded drivers that construction is still happening in the area, with work continuing on another three interchanges. Fines for speeding are doubled in construction zones when workers are present.

The province hopes a public-private partnership will start building the southeast leg of the ring road in 2010 and that it will be open by fall 2013.

Plans for the southwest leg remain unclear after members of the Tsuu T'ina First Nation rejected a deal to sell their land to the province for the road. The rebuff ended decades of negotiations and forced the provincial government back to the drawing board.