Some of the most dangerous and congested sections of Oregon Expressway/Page Mill Road from Alma Street to Foothill Expressway are being eyed for redesign to improve bike and pedestrian safety and ease traffic backups. Part of Santa Clara County's Expressway Plan 2040, the project seeks to manage traffic conditions for the next 25 years on all of the county's expressways.
Santa Clara County Roads and Airports officials will hold a public workshop regarding the Oregon-Page Mill section on Wednesday, Nov. 19 at Terman Middle School. The project includes modifying the Alma Bridge over Oregon Expressway, improving the Interstate 280/Page Mill Road interchange, improving the Junipero Serra Boulevard and Page Mill Road intersection and reconfiguring the U.S. 101/Oregon/Embarcadero interchange so traffic doesn't back up onto Oregon.
The county has installed new traffic signals and improved bike and pedestrian safety along Oregon from West Bayshore Road to Bryant Street, but many of the most troublesome spots remain to the west. Project engineers unveiled preliminary proposals for the 4.7-mile expressway at a drop-in session on Monday.
The Alma Bridge, which has four ramps, two that feed onto the westbound Oregon Expressway from a near-blind entry, would be widened to six lanes to add left urn lanes that don't currently exist and eliminate two merge ramps. Signal lights would feed traffic onto two clover leafs that would ease access and reduce traffic backups.
At the intersection of Page Mill Road and Junipero Serra/Foothill Expressway, an underpass or overpass would be built.
"It is the third worst in the entire county expressway system in terms of traffic delays," Dawn Cameron, county transportation planner, said.
In three preliminary concepts, Page Mill/Oregon Expressway would be trenched underneath Foothill Expressway. Bike and pedestrian access could be at grade. But the design could run into the Hetch Hetchy pipeline and other underground pipes and utilities, she said.
A second alternative would elevate Foothill and keep Page Mill/Oregon at ground level. A third concept would split the elevation distance so the overpass would not be as high. Page Mill would be lowered by about one-third and Foothill would be raised by two-thirds.
At the problematic Interstate 280 and Page Mill interchange, Page Mill would widen from four lanes to six, she said. With the lanes narrowed from 12 to 11 feet, "We can make the road work within the existing limits," she said.
The improvements would include better bike and pedestrian access. One concept includes a median bicycle track on Page Mill; another adds a pedestrian path under the ramps.
The project would also replace stop signs with traffic signals at the 280 off-ramps to improve bike and pedestrian safety.
County engineers say the changes are necessary to prevent severe, chronic traffic jams throughout the area's expressway system. In 2013, the county estimated there were 134,000 daily car trips made along the expressway.
In 2003, Page Mill/Oregon had some problem pockets, but by 2013 the congestion had worsened. By 2025 without improvements to roads and signals, Page Mill and Oregon could have "major" to "severe" delays along its entire length, according to engineering calculations.
In 2003, Page Mill from Interstate 280 to Porter Drive had major delays and Porter Drive to Ramos Way had minor delays; in 2013, the 280-Foothill stretch developed severe delays, with the stretch from Porter all the way to Bryant Street experiencing major delays. A stretch of Oregon from U.S. Highway 101 has gone from "some delays" to severe delays in the past 10 years.
With improvements, conditions won't be ideal in 2025, but they will switch to "minor" along most of the roadway. Major delays would still occur between 280 and Foothill and near Highway 101, according to county analysis.
Wednesday's meeting will also exhibit interactive displays and the chance for the public to weigh in on improvements for bicyclists and pedestrians. The meeting will take place at 6:30 p.m. at Terman Middle School, 655 Arastradero Road, Palo Alto.
More information and updates are available at the county Roads and Airports Department website.