Megan V. Winslow/Town Crier Commuters drive east on Arastradero Road past the Page Mill Road intersection. The “No Thru Traffic” sign pictured is one of three recently installed at key entryways to Los Altos Hills to prevent cut-through traffic.

For years, Interstate 280 commuters have relied on Los Altos Hills surface streets as shortcuts to avoid one of the highway’s most infamous bottlenecks: the southbound squeeze from four lanes to three between the El Monte Avenue and Magdalena Avenue exits.

So bad is the afternoon jam that motorists entering the interstate at Magdalena can rely on open roads to Cupertino and beyond, thanks to all that merging mayhem just to the north.

Los Altos Hills residents are not happy. Through a satisfaction survey conducted in early 2016, they identified “traffic/congestion” as the single-most important issue facing their town. Duly noted. Councilmembers responded by hiring a motorcycle deputy focused on enforcing traffic laws. The latest attempts to cut off cut-through commuters include new signs, requests to Waze and appeals to Caltrans.

Public Works Director Allen Chen’s research indicated that many savvy southbound drivers avoid the bulk of the afternoon backup by abandoning I-280 at Page Mill Road and then taking a circuitous route through town: Deer Creek Road to Arastradero Road to Purissima Road to Robleda Road to Elena Road to El Monte, where they re-enter the highway.

“It’s just like a water spout – it goes everywhere,” Chen said of the I-280 overflow.

In January, Chen contacted Waze, the Google-owned navigation app that provides users with route alternatives around jams. He asked the app to remove Purissima, Robleda and Elena roads as proposed shortcuts around the daily I-280 slowdown.

But Waze, Chen would come to learn, does not accept requests to alter routing or omit streets from its algorithm. If town officials wanted the app to change its ways, they would have to change the legal status of their roads. In May, they did, installing “No Thru Traffic” signs at three town boundary locations: Arastradero, Fremont and Purissima roads.

Waze “complied” as of May 24, according to a report from City Manager Carl Cahill issued last month.

Waze representatives declined to comment on the specifics of their dealings with Los Altos Hills, but spokeswoman Julie Mossler issued a statement to the Town Crier via email.

“If legal changes are made to the status of local roads, our local editors identify and validate it and can then update the map to reflect it,” according to the statement.

The town is now operating in a trial period to determine whether and how motorists react to the signs, and Sheriff’s Office deputies have not yet been pursuing violators, Chen said.

“It will take a little time for us to see the effect,” he said.

No effect might lead to stricter regulations; the town could, for example, replace the new signs with ones that restrict right turns during peak traffic hours, Chen noted. The trouble is, he added, such signs would likely impact residents as well.

Resolving bottlenecks

Some city staff members, including City Clerk Deborah Padovan, said they’ve already noticed a dip in traffic, but whether that’s thanks to the new signs, the Waze updates or simply the summer slowdown is too early to tell.

“(Purissima Road) used to be like a racetrack,” Padovan said June 2.

Meanwhile, Mayor Gary Waldeck is seeking to target the source of the problem: I-280’s current configuration. On May 19, he sent a letter to Caltrans District Director Bijan Sartipi proposing a freeway capacity analysis and traffic simulation model to minimize traffic delays.

“We recommend continuing four (4) lanes for both north and southbound Interstate 280 through Los Altos Hills by removing the auxiliary lanes,” Waldeck wrote. “Existing freeway section maps show 65 feet to 70 feet in this area, which is of adequate width to accommodate four (4) lanes throughout the Town’s boundary. With minimal engineering striping design, Caltrans can resolve this traffic bottleneck and relieve the traffic congestion on local streets.”

Financially speaking, it would make sense for Caltrans to consider any modification as part of its scheduled 2018-2019 pavement rehabilitation of that section of I-280, Chen said. The project, made possible through the 2016 State Highway Operation and Protection Program, involves adding specialized rubber to reduce highway noise.

As of the Town Crier’s press deadline Monday, Sartipi had not responded to Waldeck’s letter.