01 March 2010

I-70 Contraflow Considered In Colorado

The Colorado General Assembly is seriously considering a bill that would use "zipper lanes" on I-70 for a fifteen mile stretch of road from Georgetown to the Central City Parkway in the mountains to change it from a two lane in each direction system, to a three lanes in one direction and one lane in the other direction, during ski resort weekend driven periods of uneven traffic flow.

State Senator Chris Romer (D-Denver) is a major sponsor of the bill, as is State Senator Dan Gibbs, D-Silverthorne.

Traffic engineers studying the project have been lukewarm on this idea that is common sense to anyone stuck in this traffic, similar to the HOV lane approach used on parts of I-25 and US 36 between Denver and Boulder, but with a different implementation method. But, my bet is that Senator Romer is right on this one.

The mountains make any infrastructure change to the I-70 corridor exceedingly expensive, whether the soultion is some form of rail transporation, more lanes or some other solution, but the real problem is really limited to the one that this proposal identifies.

The cost would be modest:

A more permanent zipper-lane project in Massachusetts costs $1.2 million annually to operate twice a day, five days a week along a 6-mile stretch of Boston's Southeast Expressway. Barrier Systems president Chris Sanders estimated the annual cost to Colorado would be much less and that upfront costs would range from $20 million to $40 million.

In contrast, other solutions designed to address essentially the same problem cost around $1,000 million to $10,000 million and carry with them comparable or larger maintenance costs, or involve unpleasant tolls to fund "highway capacity expansion" that received bipartisan support.


Michael Malak said...

It would just move the bottleneck point. Actually, it would make it worse -- anytime a lane gets removed, it's worse than if the lane had never existed in the first place.

Is the median over the whole proposed segment already paved? If not, I'm guessing the $20 million is low. Since it came from the manufacturer of the zipper, that number might be just for the zipper equipment.

Billll said...

This is exactly the opposite of their position on the Sante Fe corridor, where rush hour congestion is dealt with by effectively narrowing a 3-lane road to two.

Of course they could cover their butts by designating the 3rd lane an HOV lane. Don't know what it's like now, but back when I went skiing, hardly anyone went alone.

Michael Malak said...

Someone posted in the comments to the Denver Post article the link to

Seems like a good idea.

Then car rental places would have to spring up at the destinations. And the car rental tax would have to be eliminated. Car rental taxes are damaging to the environment. Governments need to stop thinking of them as a tourism tax as more and more people rethink car ownership and opt for more occasional short-term rentals.