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By Dave Boyce
Almanac Staff Writer
Bikes heading westbound on Sand Hill Road as they approach Interstate 280 have the option of merging with traffic into a bike lane that, as it crosses the freeway, centers the cyclists in between two lanes of traffic, one headed for the freeway and the other up Sand Hill and on into Woodside.
A similar design is under consideration for Alpine Road as it approaches I-280, the intersection where, on Nov. 4, Los Altos Hills cyclist Lauren Ward died after a collision with a tractor trailer.
The hundreds of westbound bicycles that traverse the Alpine Road intersection every day have been making do without a bike lane. That would change with the implementation of any of four proposed designs now being looked at by the San Mateo County Public Works Department and the California Transportation Department.
Go to this link to view the four designs. Each inserts a bike lane between the lane for I-280-bound traffic and the lane into Ladera as Alpine Road passes under the freeway. The differences lie in where bikes weave into traffic and the markings indicating the bike lane.
The Almanac spoke with Assistant Civil Engineer Robin duSaint of the county public works department about the four options.
■ Option D-1 has bikes merge with vehicle traffic after the stop sign. The bike lane boundaries are marked by dotted lines at first and then solid lines further west.
■ Option D-2 has bikes split the traffic lanes and weave into traffic well before the stop sign. The boundary lines are solid for the bike lane.
■ Option D-3 is like D-1 as to where it would merge bikes and traffic, and like D-2 in that it uses solid lines to mark the bike lane. But D-3 adds pavement cross-hatching and two road signs: one ordering vehicles to yield to bikes, and another forbidding vehicles already committed to the southbound freeway to cross the bike lane and head into Ladera.
■ Option D-4 resembles D-3, including the signs, but with a substantially longer and continuous bike lane with a painted pavement.
“We prefer D-3,” Ms. duSaint said. Why? Because D-3 would merge bikes after the stop sign, the merging traffic is moving more slowly. D-2 has the merge happening before the stop sign; traffic headed to I-280 north from Alpine Road has a straight shot to the onramp, Ms. duSaint noted.
Corinne Winter, executive director of the Silicon Valley Bicycle Coalition, said she agrees that the speed of motor vehicles when merging with bikes is a major concern.
Moving from light to dark is another potential problem. With the current D-3, cyclists move west from the stop sign in full daylight, but merge with motor traffic in the relative darkness under the freeway overpass.
The bicycle coalition prefers a combination of D-3 and D-4’s painted bike lane, Ms. Winter said.
Records of the California Traffic Control Devices Committee show ongoing experiments with colored bike lanes, including in San Francisco.
To apply color at Alpine Road, San Mateo County would have to ask the committee, Ms. Winter said, adding that while she would like the county to apply, it should not delay a fix to the intersection.
The bottom line, she said, is safety. The intersection “should be safe enough for 8-year-olds to ride their bikes across,” she said.
I’ve been bike riding on Alpine road since before 280 was built. This merge was created with the freeway, but there never was a bike lane on the westbound side.
I’ve always merged the same way, even before the stop signs were added, and I’ve never really had a problem. I wait until the cars pass to turn right onto the southbound on ramp, and then move left and ride the white line. There is a long distance between the stop signs and the merge, so I usually have plenty of time to pick a good opening. The lane is wide enough that cars usually do not have a problem missing me.
But, I have had lots of problems crossing the northbound off ramp, where cars come off the freeway at 65 mph and don’t have to stop to merge onto westbound Alpine. It’s much harder to cross here. Hopefully, this fix will also address that problem.
Caltrans really needs to put a child-safe bike lane at the Page Mill Road & I-280 intersection. This is the primary route that kids take to get to the Arastradero Preserve.
I too have often riden my bike through this intersection. I find west-bound a nightmare, especially on a weekday afternoon when traffic from Alpine onto 280 is heavy enough that Ellen’s solution of “wait until there are no cars” is not really an option. I favor option D-2 as it merges in good light.
I find eastbound very scary too, as northbound cars from 280 often swing wide onto eastbound Alpine. An eastbound bike is starting from the stop sign, so is moving quite slowly…..a clear yield or stop sign on the ramp would be very helpful.
I’m pretty certain that the County would not have to ask for permission to add painted lanes, since it’s already being done elsewhere in the state…and is in fact quite common now in cities throughout the country.
A good part of the danger to cyclists is that Alpine Road is not suitable for large semis. The only reason they are on Alpine is because Stanford got Santa Clara county (as part of the GUP) to allow trucks on Junipero Serra despite the prohibition of all trucks over 7 tons on Junipero Serra. Stanford has barricaded itself off from trucks and foisted them onto all the nearby communities. Another problem is speeding and a speed limit that is also way too high for a residential neighborhood. If the cyclists got their act together and advocated more for safe bike lanes, everybody would be safer. Residents can’t do everything. People living along Alpine road have been trying for the last 20 + years to get the road safer for cyclists, pedestrians and motorists. However, the complaints have mostly fallen on deaf ears.
I would be a lot more excited about this if bike lanes could actually cause drivers to behave better. In this case they will encourage bicyclists to position themselves properly, which is half the story. They won’t do anything to the other side of the equation.
This is ridiculous. There already is a separate, dedicated bicycle path on Alpine Road. If Bicyclists don’t want to use it, then the use the motor vehicle roadways at your peril.
If you don’t think it’s adequate (as many bicyclists have used as an excuse), then upgrade it on your dime.
Bike riders pay taxes too, Outside Observer. And Alpine isn’t a “motor vehicle roadway.” Its a regular old road.
> This is ridiculous
Not as ridiculous as the lawsuit or the judgement and award of that lawsuit was, in my opinion, as sad as any loss of life is.