Oh interesting. So really the city should install a no through traffic sign to 15th when you try to enter it from California. In fact this should be done on a bunch of other streets north of California, since all of those have the same problem: 16th, 17th, 18th, 19th, 20th, 21st, 12th, 11th, 10th, 9th, 8th, maybe 14th and Funston. I wonder why the cars end up on 15th and not those other ones (or maybe they do, but the residents on those other streets don't care).

Playing with Google Maps, it seems smart enough to not route me on Lake. So I guess Waymo's route making software doesn't use all the information that Google Maps has, such as slow streets.