Heading north on 23rd Ave, the speed limit slows to 20mph part way up the hill at certain times of day for a few blocks (school zone). An officer will park at the top of the hill in a driveway or parking lot and clock down towards the bottom of the hill. There are two intersections that turn on to 23rd ave. after the initial school zone sign, with no posted school zone signs between the intersection and the end of the school zone.