This is an archived article that was published on sltrib.com in 2012, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

New express lanes on Interstate 15 in Utah County are now open not only to carpools, but also to the 12,700 drivers in the state who use transponders to pay tolls in such lanes.

Last week, the Utah Department of Transportation opened all lanes a bit early in the 26-mile stretch where it has rebuilt and widened I-15 between Lehi and Spanish Fork — even though final completion of all work is not scheduled until next month. The stretch had opened express lanes to carpools but needed some extra work on toll equipment before allowing toll-payers.

UDOT spokeswoman Tania Mashburn said Utah now has the longest continuous stretch of carpool lanes in the country: 54 miles from 2300 North in North Salt Lake to Spanish Fork. It has another stretch from Parrish Lane in Centerville to the Layton Parkway, for a total of 62 miles.

UDOT is studying adding express lanes from 2300 North in North Salt Lake to Parrish Lane, and from the Layton Parkway to 31st Street in Ogden.

That would add another 23 new miles, for a total stretch of 85 miles.

Lee Davidson