In this October file photo, northbound traffic on Interstate 19 approaches the Ajo Way.

Mike Christy / Arizona Daily Star/

Girders are going in on the new West Ajo Way bridge over Interstate 19, and that means interstate and road closures over the weekend.

Starting at 9 p.m. Friday, Oct. 13, drivers in both directions will need to exit I-19 at Ajo and immediately return to it on the on-ramp. They will not be able to exit onto Ajo, which will also be closed between 16th Ave., to the east of the interchange, and Holiday Isle, to the west. The Arizona Department of Transportation suggests Irvington Road as an alternative .

The work and closures are scheduled to end at 5 a.m. Monday.

The ramp that connects westbound Interstate 10 to I-19 will also be closed over the weekend.

Contact: mwoodhouse@tucson.com or 573-4235. On Twitter: @murphywoodhouse