A controversial plan to remove two lanes on El Camino Real and reserve them for high-speed buses would worsen traffic on two heavily traveled expressways but not delay motorists on El Camino itself, an independent audit released Tuesday showed.

A five-person outside review board examined the Santa Clara Valley Transportation Authority’s data and conclusions on narrowing the key roadway from San Jose to Palo Alto and agreed that the traffic impacts will not be dire. Its report says traffic will be affected in some locations but maybe not as badly as feared by many motorists.

This means the VTA has cleared an early key hurdle, as the board’s conclusions show skeptical city officials and drivers that the VTA plan has merit. The audit now goes to a policy advisory group and, if endorsed, would go to the 12-member VTA board for a vote by January. Support there would start the process for seeking federal funding.

“This was a robust analysis, but the findings were presented in a responsible way,” said panel co-chair Mark Spencer, vice president of the Western Institute of Transportation Engineers in Oakland. “Yes, there are going to be significant impacts, and they are not trying to hide that.

“But quite frankly, they may not be as bad as people think.”

He was joined on the audit team by David Ory of the Metropolitan Transportation Commission in Oakland, Robert Bertini of the transportation research board at Cal Poly, Caroline Rodier of the Urban Land Use and Transportation Center at UC Davis, and Karen Philbrick, executive director of the Mineta Transportation Institute in San Jose.

The VTA and its backers see the plan as a bold way to lure drivers onto sleek blue buses that can cover the 17-mile distance almost as fast as cars. The six affected cities on the route are divided on the merits of the idea.

The agency looked at 247 intersections along El Camino and nearby side streets and found that levels of delay for drivers would remain about the same as today — despite the change from three lanes to two lanes each way. Because VTA officials recognized that conclusion would generate widespread disbelief among drivers, they opted to have outside transportation experts look over their work.

Members of the review commission were not paid for their four months of effort and had no contact with the VTA. About $95,000 was paid to engineering consultants such as Iteris, based in Santa Ana, which analyzed the technical data.

“We totally get it that this would be the hardest thing to understand,” said John Ristow, the VTA’s director for planning and programming. “But the review shows that the data is accurate and complete.”

More than 700 public comments have been received on the hotly debated project, the most ever for the transit agency. Opponents have been very vocal. “It’s nuts,” said Tim Ramos, of Mountain View.

But not all agree, As traffic jams worsen, some say better transit is a must.

“I applaud the decision-makers to push this hot topic,” said Cor van de Water, of Sunnyvale. “Gridlock will only get much worse. We need to do something and the best thing is to promote solutions that are not a single occupant in a motor vehicle.”

At most intersections, the length of delays will remain the same as now, according to the audit. But traffic is expected to get worse at Page Mill Road-Oregon Expressway and Alma Avenue in Palo Alto and at heavily traveled San Tomas Expressway in Santa Clara, as some cars divert to those routes to avoid El Camino Real.

Where will all those other cars go with fewer lanes? Based on traffic models applied in other studies nationwide and in the Los Angeles area, most drivers will take other routes or make trips at less-congested times of day. Others may hop aboard a bus or bicycle.

The audit concluded that 900 vehicles per lane would no longer use El Camino. That’s the equivalent of one lane of traffic in one direction.

“We are lucky that there is a very rich and highly connected roadway system near El Camino,” Ristow said, adding that the “majority of trips will still be made by automobiles. There’s no doubt about that.”

The VTA could also recommend running express buses along the curb lane, although those buses would not enjoy a major time savings as they slog their way through traffic.

This is the first time a plan has been hatched to take a lane away from cars and assign it to transit service in Santa Clara County. Similar plans are under consideration in San Francisco on Van Ness Avenue and Geary Boulevard and in the East Bay between Oakland and San Leandro, and are sprouting up all over in Southern California.

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