From time to time we get asked, “How do we know what the maximum or minimum speed limit is if it is not posted?” Our general reply is, “You have to remember what the prima facie speed limits are.” This is a legal phrase which means “a fact presumed to be true unless it is disproved.” The “Readers Digest” version goes like this.
When we took drivers education, and for some of us that was a long time ago, we learned the different speed limits and where to use them. In Chapter 8 of the current Texas Drivers Handbook, it lists the speed limits of different vehicles on different types of roads. In urban districts, the maximum speed limit is 30mph, unless otherwise posted, whereas on a beach or in an alley it is 15mph. These speed limits apply daytime or nighttime. Urban districts are residential areas, whether right next to or away from highways or interstates. On a highway numbered by this state or the US, it is 70mph. This applies to all vehicles except school buses.
The list continues on but I will not go through each one of them. These speed limits are found in Section 545.352 of the Texas Transportation Code which is entitled, “Prima Facie Speed Limits.” If you find yourself in an area without a posted speed sign, look around to see what type of territory it is, and then make the proper speed adjustment.