Twenty Means Twenty (Except…)

Q: Bellingham has a new black and white 20 mph speed limit sign that includes “city wide” and “unless otherwise posted.” On a road I drive, I see the sign and assume the limit is now 20. It’s not until a while down the road that I see a 35-mph sign. I asked about the sign and was told, “Please understand it’s not a speed limit sign. It’s an informational sign for residential areas without posted speed limits.” How can one determine if a speed limit sign is informational or regulatory? There’s a similar situation leading up to a 55-mph state highway.

A: Right now I’m aware of four cities in Washington with 20-mph default speed limits. More cities are considering it, and I wouldn’t be surprised if it becomes a widespread trend in areas with high pedestrian traffic. Slower speeds in neighborhoods and downtown areas don’t change travel time much (the real delays are stop signs and traffic lights) while making a big difference in pedestrian safety. But what do those 20-mph signs really mean?

You can only fit so much information on a traffic sign. One thing you can communicate without adding more words is the authority of the sign. Some signs are there to provide information, like the blue signs showing what’s available at the next exit, or brown signs letting you know about recreational areas. Black and white signs are not informational – those are the rules. Ignore them at your peril.

Maybe your question didn’t make it to the right person; I checked back with the city and they replied, “The signs recently installed on streets entering Bellingham let drivers know that our default speed limit is now 20 mph unless otherwise posted. These are regulatory signs, and the 20-mph default applies anywhere a different speed limit isn’t posted.”

So what do you do if you see the “city wide” 20-mph sign on a road that seems like it should have a much higher limit? You can probably ignore it. That sounds like a contradiction to what I just wrote, so let me explain. A sign can’t always express the entirety of the law. For example, a “keep right except to pass” sign leaves out four other exceptions to the “keep right” law. The “city wide” part of the new speed limit sign actually has a couple exceptions too.

Washington has some default speed limits written into the law: 25 mph on city streets, 50 mph on county roads, and 60 mph on state highways. A few other laws permit decreases and increases to the default limits based on what’s appropriate for a particular road. Your city is letting drivers know that it has decreased the speed limit throughout the city below the state’s default limit.

However, the law that permits lowering city-wide speed limits to 20 mph only applies to non-arterial streets. If there was room on the sign, it might read, “citywide, except on arterial roads and state highways as specified by the Revised Code of Washington and the Citywide Speed Limit Policy.” Generally those streets will be clearly posted, but it’s possible you could turn from a minor side street onto an arterial or highway and not see a speed limit sign for a bit, as the rules direct that speed limit signs be posted after major intersections.

Practically speaking, if you’re driving through a neighborhood or downtown area you’d be wise to assume the speed limit is 20 mph. On an arterial or state highway, do what you’ve always done (assuming that you’ve previously always followed the posted speed limit.)