That map shows where SDOT is planning speed humps to slow drivers near Arbor Heights Elementary and Westside School (WSB sponsor). We contacted SDOT for more details after a postcard landed in Arbor Heights mailboxes and reader Andrew forwarded it as an FYI. The map (here’s a PDF version) shows 29 speed humps planned for streets that already have 20 mph school-zone signage, says SDOT spokesperson Ethan Bergerson. He adds that this is part of the Safe Routes to School program. Construction isn’t scheduled yet, he says, but won’t happen any earlier than May; the mailer was meant to be an early warning of sorts.
ADDED WEDNESDAY: SDOT explains the color-coding as – red for speed humps, blue for speed cushions. Here’s an explanation of how they differ.