The method of determining the speed limit for a particular roadway is largely determined by the state statute, as well as the MUTCD, TGM and the governing authority for that roadway. In Menomonee Falls, a road could be under the authority of the State of Wisconsin, Waukesha County, Washington County or Menomonee Falls. Most of the residential streets in Menomonee Falls are under the village's jurisdiction with a few exceptions, which are privately owned streets.
The most widely used method for determining an appropriate speed for a roadway is referred to as the 85th percentile method. A midweek study is conducted of vehicle speeds using the familiar road tubes. The results are reviewed to determine what speed 85% of the traffic is traveling. Setting a speed within 5 mph of the 85th percentile is the acceptable practice. This helps to ensure voluntary speed compliance, diminishes the chances for speed disparity collisions (someone going too slow while another is going too fast), and avoids claims of a "speed trap".
Other factors that can enter into setting speed limits are crash history, traffic patterns and engineering characteristics of the roadway. With advances in roadway and vehicle design, lowering speed limits has become much more difficult than raising it. However, it is possible to have a speed limit reviewed by calling or emailing the Menomonee Falls Police Department Traffic Unit.