Traffic Studies


The Londonderry Police Department has several available tools to allow us to collect data on the roads traveled.  One of the familiar ones you may have seen around town and on our Facebook page is our Speed Awareness Monitor otherwise known as SAM.  SAM is the mobile radar sign that displays the current vehicle’s speed which is passing SAM.  You may not realize that all the vehicles which pass SAM are recorded as data.  From this data we are able to see how many vehicles are traveling based on direction, time, and speed.

Another more discreet tool which the Londonderry Police has is known as a Jamar.  These units do not stand out to the general public and do not display visible information.  The units are able to collect volume, direction of travel, speed, length of vehicle, and class of vehicle. 

Using the tools above we are able to analyze stretches of roadway.  We are able to get the total amount of vehicles that traveled during a designated time along with peak volume times.  The data provided also gives us the average speed that motorist travel along with percentages of people who travel above or below the speed limit.  We are able to use this data to better direct traffic enforcement for peak violation times and locations.


Study Results