Airport tunnel deal finalized

The city and the Calgary Airport Authority have finalized a long-sought deal to build a tunnel under a new runway, officials announced Friday.

The runway's construction forced the closure of Barlow Trail between 48th Avenue and Airport Road N.E. in April.

A tunnel will compensate for the loss of that route to the airport by going under the runway, linking Airport Trail (96th Avenue N.E.) on the west side with 36th Street N.E. on the other side.

Under the terms of the lease agreement that was signed on Thursday, the airport authority will contribute roughly 24 hectares of land worth an estimated $50 million for the Airport Trail extension and future interchanges.

During negotiations that lasted several months, airport officials said they would allow the tunnel's construction only if the city committed to additional interchanges, one at 19th Street and one at Barlow Trail. But under the agreement, those improvements will be completed at a later date.

The project "preserves a critical road and transit corridor for all Calgarians," said Mayor Naheed Nenshi in a written statement.

A tunnel is also the best way to eventually extend LRT service to the airport terminal from the northeast LRT line, city officials said.

The project will be constructed in three stages. Stage one consists of:

• Construction of the tunnel under the new runway.
• Widening Airport Trail between Deerfoot Trail and Barlow Trail to six lanes.
• Extending Airport Trail through the tunnel to 36th Street N.E.

The estimated cost of the first stage is $280 million, the city said. In February council approved a budget of $294.8 million for the project.

The second and third stages of the project "will be addressed as funding sources are identified and secured and subject to Council approval of the necessary budgets," the city said.

Stage two will include the construction of interchanges along Airport Trail at Barlow Trail and 19 Street N.E. as well as extending Airport Trail to Metis Trail. The City will pay $50 million and the airport will contribute $20 million to the cost of the stage two interchanges.

In stage three the city and the airport will split the cost of building upgraded interchanges to "provide access and egress from Airport Trail to the airport when warranted by traffic levels", which is not anticipated for 20 to 30 years, the city said.

Construction of the tunnel will start in the next few weeks. It is slated to be open to traffic in 2014, in conjunction with completion of the new runway.