Traffic Engineering

"Why Not a Lower Speed Limit to Reduce Hazards in Our Area?"

An unrealistically low speed limit can actually lead to accidents. Here's why:

First, many studies conducted over several decades in all parts of the country have shown that a driver's speed is influenced more by the appearance of the roadway and the prevailing traffic conditions than it is by the posted speed limit.
Second, some drivers will obey the lower posted speed while others will feel it's unreasonable and simply ignore it. This disrupts the uniform traffic flow and increases accident potential between the faster and the slower drivers.
Third, when traffic is traveling at different speeds, the number of breaks in traffic to permit safe crossing is reduced. Pedestrians also have greater difficulty in judging the speed of approaching vehicles.

Local authorities may post speed limits, but the speed limits should always be based on traffic engineering survey which include an analysis of roadway conditions, accident records and the prevailing speed of prudent drivers.

Colorado's basic speed law says drivers must observe maximum speed limits and must also drive at a speed "not greater than nor less than is reasonable" ... and no person shall drive any vehicle upon a highway at a speed greater than will permit him to bring it to a stop within the assured clear distance ahead.

Under Colorado law, speed limits on City streets are called prima facie limits - those safe and prudent under normal conditions. These limits include 25 miles per hour in business and 30 miles per hour in residential districts and 20 miles per hour in school zones when children are going to and from school. These speeds aren't always posted, but motorists are required to know them.