Chilly Nights Delay Completion of Project to Widen, Improve Ventura Freeway : Transportation: The $40-million undertaking will not be finished until June or July. The work must be done during the night to avoid disrupting traffic.

A 2 1/2-year effort to widen and improve the Ventura Freeway--one of the nation’s busiest--was running on schedule until about December when Mother Nature decided to put a chill on the project.

Completion of the $40-million project was expected in April but will be delayed until June or July because nighttime temperatures have been too cold for workers to place a final layer of asphalt on a section of freeway between Hayvenhurst Avenue and Van Nuys Boulevard.

For the asphalt to be pliable enough to work with, the nighttime temperatures must be 50 degrees or higher, said California Department of Transportation officials.

“It cools too rapidly and we can’t compact it to its required density,” said Keith Eoff, the project’s senior resident engineer. “When it’s too cold, you get poor adhesion and the life expectancy would be drastically reduced.”

Such work would be no problem during the day when temperatures are a pleasant 63 degrees, but the asphalt work must be done at night so that it won’t disrupt daytime traffic.

Jim McAllister, another resident engineer on the project, said the project is 70% complete. He said the asphalt work had to be halted about Christmas.

Eoff said Caltrans officials had expected temperatures to drop during winter months. But he said they had hoped to get more asphalt on the road before the cold weather set in.

“We paved continuously once we were in the position to pave,” he said. “We were well aware that it was going to get cold.”

Nighttime temperatures Monday were at a low of 43 degrees in Woodland Hills and 47 degrees in Northridge. Weather forecasters predict that nighttime temperatures will continue for the next three to five days to range between 37 and 51 degrees in the Los Angeles Basin.

“We monitor the weather daily to see if we have a trend where we can expect temperatures above 50,” Eoff said.

Cold temperatures also delayed for about a month the installation of a final layer of asphalt on a new mile-long stretch of the Antelope Valley Freeway in Santa Clarita. Temperatures eventually rose enough to let workers lay the asphalt, but striping and other work must be completed before the additional southbound lane between Lost Canyon and Sand Canyon roads opens this month, Caltrans officials said.

But road crews working on the Ventura Freeway Improvement Project are not cooling their heels. Work continues on other aspects of the project, such as installing drainage grates along the improved areas of the freeway.

The improvements are meant to help ease the ever-increasing traffic flow. On a typical weekday, an average of 277,000 vehicles use the Ventura Freeway between the San Diego Freeway and Hayvenhurst Avenue.

When completed, the project will add a sixth eastbound lane from Hayvenhurst Avenue to the San Diego Freeway interchange, a fifth eastbound lane from Wilbur Avenue in Woodland Hills to the Hollywood Freeway interchange, and a fifth westbound lane from the Hollywood Freeway to Van Nuys Boulevard and from White Oak to Wilbur avenues.

The 15-mile project includes the widening of bridges, the repair and resurfacing of freeway pavement, the reconstruction of various ramps and the addition of retaining and sound walls eastbound from Hayvenhurst to Haskell avenues, and westbound from Van Nuys to Sepulveda boulevards.

To keep the project from stalling daytime traffic, work has been generally limited to the hours between 9 p.m. and 6 a.m. on weekdays and 10 p.m. and 11 a.m. on weekends. Caltrans has also installed “gawk” barriers along work areas to prevent motorists from slowing to look at construction activity.