South campus drivers, pay attention! A massive underground construction project is scheduled to start soon, bringing traffic slowdowns, road closures and detours, some of which could last for more than a year.

"Expect delays," project manager Julie Sams said. "Your travel time will be significantly impacted."

Pedestrians and bicyclists can expect to see detours, too, especially along the arboretum waterway in the vicinity of the California Avenue bridge.

Most of the commotion will be due to the extension of utility lines to the Robert Mondavi Institute for Wine and Food Science, now being built on Old Davis Road, and the Physical Sciences Expansion site at California Avenue and La Rue Road.

Workers also will build a short, eastward extension of Old Davis Road to provide access to the campus's forthcoming hotel and conference center, and new Graduate School of Management. They will go west of the landscaped square in front of the Buehler Alumni and Visitors Center.

The utility work and the road extension are part of a single contract worth about $19 million, according to the Office of Resource Management and Planning.

Starting as early as next week, drivers can expect lane closures and slowdowns on La Rue Road between Dairy Road and California Avenue until August 2008, and closures and slowdowns on Old Davis Road during the same period — that is, except for this summer when a portion of Old Davis Road is scheduled to be closed.

During the Old Davis Road closure, the university plans to divert traffic onto Arboretum Drive (also known as "Old" Old Davis Road) behind the Mondavi Center for the Performing Arts. This road intersects with Mrak Hall Drive, which drivers can use to get to and from the south entry garage and nearby parking lots.

To further complicate matters, the university this summer also plans to close the California Avenue bridge over the arboretum waterway, from about the end of June to the end of September.

The university had planned a detour on a temporary road across an existing land bridge — where the waterway runs through a culvert. The bridge lies between Old Davis Road and Putah Creek Lodge Road, and that road connects to La Rue Road.

California Avenue bridge to close temporarily

However, the university no longer plans to build that detour. So, if you normally enter campus from the south, off Interstate 80, and take the California Avenue bridge to get to La Rue Road, be advised: The bridge will be closed and there will be no detour this summer.

Sams said the recommended alternative is the campus's west entry at Hutchison Drive off Highway 113.

She said drivers are encouraged to take this route even when the California Avenue bridge is open, as a way to avoid construction work on Old Davis Road.

Some people have no other choice but to take Old Davis Road to get to the south entry garage and nearby parking lots, as well as the Mrak Hall parking lot.

"You will have passage, but you will be driving in a construction zone with flagmen," Sams said.

While drivers are negotiating detours and slowdowns, construction crews will be putting in pipelines carrying water, chilled water and steam, and other pipelines for electric and telecommunications lines.

Sams said the contractor will set up a staging area in parking lot 47A, at the corner of La Rue and Dairy roads. When the contractor moves in, Sams said, this lot will be closed to regular parking indefinitely.

Sams said street parking will be prohibited along La Rue between California Avenue and Dairy Road, to give the contractor room to work. She urged caution on this section of La Rue: It has no bicycle lanes, and when construction begins, it will become even more congested — with drivers, bicyclists and construction vehicles sharing narrow lanes.

Drivers can expect to see plenty of signs to warn of construction activity, lane closures and detours, Sams said.

Similarly, she added, pedestrians and bicyclists will see plenty of detour signs along the waterway on both sides of the California Avenue bridge.