Parsons Corp. will head a team that will design and construct the northeast portion of the Calgary Ring Road around Alberta, Canada.

Joining Pasadena-based Parsons in constructing the 13-mile portion of the ring will be Longmont, Colo.-based Flatiron Constructors Inc. and Calgary-based Graham Construction and Engineering.

The project is a public-private partnership in which a private entity, in this case, Wiesbaden, Germany-based Bilfinger Berger BOT Inc., is funding the improvements and will operate and maintain the roadway for the next 30 years.

The first portion of the ring road will be a roughly 10-mile stretch in northwest Calgary and will include 23 bridge structures and six interchanges, Parsons said. The first stage of the project is to be finished next fall and the entire project is to be completed in 2009.

Parsons is a privately held construction and engineering firm. It had revenues of more than $3 billion in 2005.