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No new asphalt for Highway 85 - Caltrans pushing for grinding
VTA wants to conduct grind test beginning this summer
News souring for residents
By Oakley Brooks
Saratoga residents have been dreaming of a fresh layer of asphalt on Highway 85 ever since the Santa Clara Valley Transit Authority received $9.3 million in 1999 to dampen the road's constant hum.
But they won't get their wish.
Caltrans, which has the ultimate say in state highway management, will not consider an asphalt overlay, according to a leading VTA official.
Mike Evanhoe, the VTA's congestion management and highway programs director, told a gathering of citizens in Saratoga last week that his agency would like to test a new technique for grinding the rainwater grooves on Highway 85. The method might give a sound reduction similar to an asphalt layer.
More important, grinding, according to Evanhoe, is the only option Caltrans has given him.
"That is why we're looking at this new style," he said recently.
Evanhoe told the group of residents that Caltrans' policy has been to install asphalt only where a highway's concrete is failing. Seven-year-old Highway 85 is still in good shape, Evanhoe said. And that rules out a new layer of asphalt on the designated corridor between Interstate 280 and Highway 87.
The announcement was a blow to many Saratogans, who have been complaining about noise from the freeway since cars first sliced through their backyards in October 1994.
"The asphalt is so noticeably different, it's such a quick Rx," said Jim Stallman, who lives near St. Andrew's School but still hears the freeway drone. "That's what we wanted and we wanted it four years ago." Transit officials have said in the past that the noise from tires on the highway's grooved cement was exacerbated in Saratoga by a bouncing effect due to the depressed roadway and the high sound walls, both of which residents requested.
Not long after the Santa Clara County Board of Supervisors gave VTA the sound mitigation money in July 1999, as part of a half-cent sales tax increase county voters agreed to in 1996, the tug of war on how to spend the money began.
Residents, including members of a self-appointed Freeway Noise Abatement Committee, pushed for a new layer of asphalt mixed with ground tire rubber to dampen the sound. Caltrans' own study showed that asphalt would reduce the noise level four to six decibels. (Saratogans have measured Highway 85's decibel level in the high 60s, from houses adjoining the freeway.)
Initially, Caltrans officials said an asphalt layer might peel off the new concrete on Highway 85.
Then, Caltrans began studying a technique on grinding the rainwater grooves on Highway 101 in Sonoma County. The grinding produced some decibel reduction but still wasn't as effective as asphalt. Last year, Evanhoe came to the Saratoga City Council to pitch the idea of micro-grinding--which would use diamond-headed machinery to reduce the grooves even more than standard grinding.
Because Highway 85 is one of only a handful of freeways in the state without truck traffic, Evanhoe said grinding would allow the concrete to last up to 30 years before major maintenance would be needed. Asphalt's sound-dampening qualities could diminish within seven to eight years, as oil and dirt fill in the porous surface. Potholes could also begin to form as the asphalt lifts from the concrete base, and Caltrans did not want to take on added maintenance.
Meanwhile, residents have continued to lobby for an asphalt overlay.
One committee member, Robert Karlak, even filmed his own video to show the drastic sound difference between asphalt on other roads in the county and the concrete on Highway 85. He said his measurements also show no difference in sound between Highway 85 and a section of Interstate 680 where the grooves were ground down with traditional methods.
Evanhoe said recently he is uncertain exactly how much the new micro-grinding technique will reduce sound--a Caltrans test of the technique has been dragging behind schedule on Interstate 280 through Woodside.
But he and the rest of the county will apparently find out soon.
The county's mayors and city managers have asked him to go ahead with the micro-grinding study to determine if it is indeed comparable to an asphalt layer.
He anticipates that the VTA board will approve the test at the board's annual meeting in April.
The trial could begin as early as May.
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Saratoga, California Since 1955
