The Effects of Speed Limits

The June 6 editorial “Keeping Pedestrians Safe” takes the city of Santa Ana to task for raising the speed limit on a portion of West First Street and states that reducing the speed limit would be appropriate. This demonstrates a lack of understanding of California law as it pertains to the setting of speed limits. Equally as disappointing, it perpetuates the myth that changing the speed limit will change motorists’ behavior.

A check with city staff would have revealed that the speed limit was adjusted specifically to allow the Police Department to utilize radar to enforce against speeders. The California Vehicle Code provides that a street segment with an improper speed limit (as defined by the state) is a speed trap and that the use of radar to enforce speeds is illegal.

In my 25 years as a professional traffic engineer, I have conducted numerous studies to evaluate the effectiveness of new or changed signage. These studies have consistently shown that traffic speeds are largely unaffected by speed limit signage. The great majority of drivers travel at a speed they feel comfortable with based upon the type of road and their surroundings. Speed limit signs mainly help people who are unfamiliar with a particular roadway.

Properly posted speed limits are largely self-enforcing. Posting a lower speed limit merely makes “violators” out of a much larger proportion of drivers.

RICHARD M. EDMONSTON, Fountain Valley