California once tried ‘weave’ signs to ease merging problems: Roadshow

Q: I haven’t driven in the vicinity of the interchange from southbound Interstate 280 to southbound 880 since it was re-engineered, so I don’t remember the exact placement of a sign saying “Weave.” Do your Caltrans contacts know the history of that sign’s usage around the state?

“Weave” seems like very pragmatic guidance if you accept that accommodating some access onto a freeway must ultimately be a cooperative maneuver.

I always read a “weave” sign as an instruction to alternate. Even if it wasn’t clear to all drivers exactly what Caltrans meant by it, it served as a subtle reminder about the social contract that, hopefully, extends to manners on the road.

Gary Garnier, Eden Prairie, MN

A: The signs were put up back in the 1970s at the 880-101 interchange in San Jose. The interchange was a really tight and full cloverleaf.

Traffic engineer M.E. Hardin came up with the idea to have the “weave” signs to get people’s attention and reduce the number of cars running into each other. The signs were placed at the off-ramps and on-ramps. They showed lane markers and read “Weave.” They were up for quite a while, but were never made permanent anywhere.

Q: During my frequent trips between Cupertino and Placerville, I constantly see construction zones on interstates 680 and 80 and Highway 50 with lighted signage stating, “55 mph limit will be enforced.” I am always bemused by this and left wondering when that enforcement will occur (as it assuredly is not currently, based on all of my trips).

Would Caltrans consider adding the date it actually will be enforced, or (preferably with the cooperation and action of the CHP) change the message to: “55 mph is being enforced”?

Steve Lebus, Cupertino

A: The speed limit is 65 mph, but in most construction zones, it is 55 mph. I understand your point, though, about how posting a speed limit does not mean it is being regularly enforced there, or adhered to by drivers.

Q: Responding to Tuesday’s question about double yellow lines: You can make left turns and U-turns across double yellow lines, unless there is a sign saying you can’t. It’s two sets of double yellow lines that you can’t cross. They are considered an island.