The proposed area is a 15-mile stretch between Floyd Hill and Empire, where, during high traffic times, two lanes of I-70 could be transformed into three lanes going one direction, and only one lane going the other.
Stacy Stegman with CDOT says the study shows that the best benefit would be on Sunday afternoons during ski season, when a zipper lane would cut the eastbound commute time by 50 percent, but double westbound traffic in that single lane.
"So if it takes you 80 minutes, it will take you 40 minutes, but for those going westbound, it's not so good. You're going to double your travel times," Stegman said.
The study found that westbound traffic times would go from 35 minutes to 79 minutes.
Even though mountain-bound traffic is heavy on Friday afternoon and Saturday morning during ski season, the study found it wasn't heavy enough for long enough periods to justify opening an extra westbound lane. It can take up to 1 1/2 hours to set up a reversible lane.
The temporary lane would run 15 miles on eastbound I-70 from west of Empire Junction and continue to Floyd Hill, and would cost between $30 and $35 million to implement.
The study found summer travel times would not work with a zipper lane because there is so much traffic heading both east and west at different times during the day.
State legislators like Rep. Christine Scanlan (D-Summit County) helped speed up the study asking CDOT to put the pedal down to find out if a zipper lane would work.
"While I'm disappointed in some of the results of this study, I am still hopeful that CDOT will find a workable and affordable solution. Even a short 5 or 10 mile zipper lane at peak weekend hours could provide some relief for drivers and help for our mountain communities. CDOT will do another study and I hope it shows that this is doable to help drivers, skiers, and our economy," Scanlan said.
The second phase of CDOT's study will wrap up by early 2011 with a focus on safety and snow removal issues.
The earliest the lane could be used is in the 2011-12 ski season.
(KUSA-TV © 2010 Multimedia Holdings Corporation with The Associated Press)