California roads speed limits for different areas / zones

School zone or when children are around
The speed limit when driving within 500 to 1,000 feet of a school while children are present is 25 mph unless otherwise posted.

school sign 25mph

(There is a confusion around school zone speed limit as to whether you should follow the speed limit of 25 mph when school is not in session or when there are no children present. When you are driving, it is difficult to tell from 1,000 feet if there is a school session or children are present. Even if it is Saturday or Sunday, children may be attending a school event such as a sport competition or can be at a playground nearby. Children do not have a sense of detecting street danger and may run cross the street after a ball or there may be excited to run home. So, it is better to be safe than sorry; slow down to the school zone speed limit near a school zone or a playground when children may be present.)

residential street 25mph

Residential or Business Areas
The speed limit in the residential or business areas is 25 mph unless otherwise posted.

Safety Zone (Near Streetcars, Trolleys, or Buses)
A safety zone is an area of the road where street cars or trolleys are sharing the road with you. A safety zone is marked using raised buttons or markers.
The passing speed limit, when it is safe to pass, is 10 mph or less.

Alleys
The speed limit for alleys are 15 mph.

Blind Intersections
The speed limit for a blind intersection is 15 mph.
A blind intersection is an intersection without a stop sign and as you approach the intersection within 100 feet, you cannot see the cross the traffic from either direction from 100 feet.

trolly bus

Near Railroad Tracks
When you approach a railroad track within 100 feet, and you cannot see the train from either direction from 100 feet, the speed limit is 15 mph. The speed limit within the 100 feet of a railroad crossing