Bypass project under way

A lot of ground is moving around right now at the future location of the East Sonora Bypass on Highway 108.

About three months into construction of the multi-million dollar highway project, crews can already be seen blasting rock and building pillars. The blasting is scheduled to continue today. Caltrans announced this week that motorists and residents can expect some nearby blasts from 4 to 5 p.m. 

Traffic should not be impacted, according to Caltrans.

Work is expected to continue on this phase, the second of three, until summer 2014. And when completed, local officials say it will be one of the largest, and most impactful, road projects the county has seen in decades.

According to Caltrans spokeswoman Angela DaPrato, it’s been 25 years since the original Highway 108 bypass was built as a two-lane highway between Mono Way and Highway 49 to route motorists away from downtown Sonora.

Since then, Highway 108 has become an “important trans-Sierra route” used by thousands of drivers for commuting, tourism and other reasons, DaPrato told The Union Democrat on Thursday. It is now one of the most congested routes in the county.

The project will “enhance this vital artery that is critical to inter-regional commuters within the surrounding Sierra and Mother Lode communities,” DaPrato said in an email.

According to state traffic data, an average of 22,300 vehicles pass along Highway 108 in the bypass every day. During peak summer months, that average goes up to 24,600.

The stretch passing through East Sonora is the heaviest travelled section of Highway 108 outside of the busiest part in city of Modesto, according to state traffic statistics from 2011.

Those aren’t the only numbers associated with this phase of the bypass. When it’s complete, as much as 6,500 cubic yards of concrete will be used for two miles of highway, 1,049 feet of bridges and 2,500 feet of frontage road at Gold Queen and Argyle roads.

Between 40 and 50 Caltrans and other employees will be working at different times on the $53 million project which was contracted earlier this year to Teichert/MCM Construction, according to Caltrans.

The project will include two elevated stretches, rising 100 to 110 feet above Mono Way and 50 to 60 feet over Peaceful Oak.

There are also piles of boulders moved on the site by crews as they build, and those boulders will eventually be placed throughout the project site.

“Projects of this nature take time to develop, design, fund and ultimately construct,” DaPrato said, noting that it has been a joint effort between the state and the local Tuolumne County Transportation Council.

This phase, when complete, will be a two-lane highway which will run from Peaceful Oak to Via Este Road. It will also include a partial interchange and Peaceful Oak, a grade separation at Mono Way and a frontage road.

The first phase was completed in 2002. Once all three phases are completed, the entire bypass is expected to run from Sanguinetti Road in Sonora to the four-lane stretch at Twain Harte Drive.

The state initially announced in 2006 that Phase 2 was fully funded and set for construction to run from 2010 through 2012.

However, the project stalled due to state funding issues before officials were able to find available funds from multiple sources.

Money was secured through the Proposition 1B-created Corridor Mobility Improvement Account and a 2006 voter-approved transportation bond. But not before a few cutbacks led to a re-design, with the updated plan excluding two entrance and exit ramps. State and local planners have said they will try to find funding to add those ramps after the second phase.

No funding source or timeline has been identified so far for the third phase of the project.