They came from as far away as Nevada City and Garden Valley in El Dorado County. More than 70 people showed up for last Thursday’s open house hosted by Caltrans at the railroad depot.

Beginning next April, reconstruction work on I-80 from Colfax to Alta will create major disruptions of traffic during nighttime hours throughout late spring, the entire summer and early fall.

Trucks and busses will be detoured at Auburn and Yuba Gap onto highways 49 and 20 to bypass the construction zone. The detour will add approximately 40 minutes to travel time, Caltrans estimates.

Eastbound light vehicle traffic will be detoured at the Colfax/Highway 174 and Secret Town Road interchanges. Motorists will be diverted onto Highway 174, Rollins Lake and Magra roads, adding about 10 minutes travel time.

In addition, I-80 will only be closed in one direction at a time.

Nighttime construction will be curtailed on weekends, holidays and other times of unusually high traffic flow, said Douglas Lange, project manager for what is being called the Colfax/Gold Run III Pavement Rehabilitation Project.

Although the two-location reconstruction project was originally estimated to take two summer construction seasons to complete, Lange said current plans call for the entire project to be finished by fall of 2009.

Location 1 covers the stretch of I-80 from Colfax to Secret Town Road. Location 2 extends from Secret Town to just west of the Alta Road Undercrossing.

Only work on Location 1 will require detours, Lange said. Location 2 will only involve lane closures.

Planned improvements include a six-inch asphalt overlay, improving water drainage, replacing the median barrier and guardrails and upgrading road shoulders as well as extensive repairs to bridges.

The $70 million project is being funded by Grant Anticipation Revenue Vehicle (GARVEE) bonds, according to Caltrans literature.

Reacting to a letter to the editor from Cape Horn resident Dan Dove, Lange told the Record the Caltrans project team would investigate the possibility of reopening an emergency-only exit in the Cape Horn area to improve fire and rescue response time.

Closer to the beginning of construction, Caltrans will post an informational website and conduct additional public information efforts for I-80 travelers along the San Francisco to Reno corridor, Lange concluded.