Here’s a question from a reader:

What are the poles with the solar panels that are installed along Highway 101? M.W.

The answer comes from Caltrans spokesman Robert Haus, who says they’re transmission towers. Embedded in the pavement along Highway 101 are sensors that can track the number of vehicles and the velocity of the traffic. That data goes to a microwave relay unit on a pole and that data is sent to Caltrans’ Traffic Management Center, or “Mission Control,” in Oakland. There, Caltrans workers can monitor traffic along 101 as well as highways around the Bay Area.

Here’s another Highway 101 question:

Why are the carpool signs on the freeway median turned at an angle that makes them difficult to read? All other freeway signage is perpendicular to traffic and much easier to read from further distances. Richard

The answer again comes from Haus, who says the median strip along some stretches of Highway 101 is narrower than others, and the signs are tilted to help prevent them from getting clipped by trucks that may stray into the median for whatever reason.


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