AT LONG LAST: Southbound MoPac toll lane opens Saturday morning

2:35 p.m Friday, Oct. 27, 2017 Local

After four years of construction and $233 million in spending, the final stretch of the MoPac Boulevard toll lane project opens Saturday to drivers.

The southbound toll lane, which runs 11 miles from Parmer Lane to the Cesar Chavez Street/Fifth Street exit to downtown, will open at 8 a.m. Drivers can take the entire stretch, which is broken down into two segments, or they can enter or exit the toll lane between Far West Boulevard and RM 2222.

“This weekend marks a significant milestone for Austin commuters,” Ray Wilkerson, chairman of the Central Texas Regional Mobility Authority board, said in a statement. “With the Express Lane open to traffic in both directions, this innovative congestion management tool will be able to fully function as it was intended.”

The northbound toll lane opened in phases, with the first leg from Far West Boulevard to Parmer Lane welcoming drivers in October 2016. The barricades came down in the rest of the northbound lane, from downtown to Far West, three weekends ago.

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The MoPac toll lanes are the first in the Austin area to have variable pricing, with a 25-cent minimum per segment and no upper limit (the total northbound rate, for instance, briefly reached $8.38 earlier this month). The rate goes up as more cars go into the toll lane, then falls as the toll lane becomes underused, with signs before each segment alerting drivers to the current price. The goal of this supply-and-demand price structure is to discourage congestion so drivers can expect at least a 45 mph trip in the toll lane.

But the impact on drivers in the free lanes has been mixed. Officials with the mobility authority, which oversaw the toll lane project, note that the toll lanes are bound to ease traffic for everyone by removing some cars that would otherwise be in the free lanes.

On the southbound stretch, however, downtown drivers entering MoPac from Winsted Lane no longer have their own lane joining MoPac, as the road was restriped to provide a dedicated lane for cars reaching the end of the toll lane. That shift, which went into effect this week, has created significant backups for commuters coming from downtown and the University of Texas areas.

And, as commuters are painfully aware, construction ran twice as long as officials expected because of a variety of challenges: stubborn limestone, labor shortages, bad weather, design delays for relocating a city water main and old utility lines encountered along the way.

FINAL TAB: Here’s the breakdown of MoPac’s total cost

The price tag grew, too: The mobility authority hired contractor CH2M to design and build the project for $137 million, but will end up paying the firm nearly $160 million as part of a settlement reached last month. That’s still just a fraction of the $375 million that CH2M has said it spent doing the work, with the firm swallowing much of that loss.

The mobility authority’s total cost will be about $233 million, counting asbestos abatement of old MoPac retaining walls done by another contractor, the preliminary design and environmental work completed before CH2M came on board in 2013, project oversight by an engineering firm, and a handful of remaining minor projects along the road that will be performed by another company.

The project’s original budget, based primarily on available grants to the mobility authority from the Texas Department of Transportation, was $203 million. It is borrowing an additional $25 million and pulling $5 million from its reserves to make up the shortfall.

The opening of the southbound toll lane doesn’t mean construction is finished: Work on sound walls, landscaping and other finishing touches will continue for months.

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But mobility authority officials say Saturday’s opening marks a critical moment for drivers to finally get the full benefit of the toll lane project.

“We are excited to deliver this important project for Central Texas,” Nikelle Meade, vice chair of the mobility authority’s board, said in a statement. “With our region’s limited north-south corridors at or nearing capacity, the MoPac Express Lane is critical to preserving our quality of life and ability to move from place to place.”