Best Practice

BEST PRACTICE:

A5−2: Work Zone Speed Limit Reduction and Speeding Fine Program

DESCRIPTION:

North Carolina Department of Transportation (NCDOT) has a criteria−based program to determine when to use speed limit reductions and increased speeding fine penalties in work zones. NCDOT uses two different methods and criteria for establishing work zone speed limit reductions. The first, and most often implemented, is a temporary speed limit reduction that uses portable devices (portable changeable message signs or portable signs) to reduce the speed limit. This application is used for short−term applications of up to 30 days. For more long−term needs, the work zone speed limit is reduced using standard speed limit signs. This second approach is normally used in work zones where significant changes to lane geometry have occurred, lane widths are significantly reduced, and/or where the shoulders have been essentially eliminated. The temporary speed limit reductions are typically used to improve worker safety during lane closure activities. The long term speed limit reductions are typically targeted to improve motorist safety due to work zone conditions. The $250 speeding fine signs are used for both applications. Speed limit reductions and the $250 speeding fine have to be approved by the State Traffic Engineer before being implemented.

REASON(S) FOR ADOPTING:

NCDOT needed to differentiate between "activities" that warranted temporary speed limit reductions and "projects" that needed long−term speed limit reductions. By having separate methods, NCDOT was able to remove ineffective and often ignored speed limit signs in the work zone.

PRIMARY BENEFIT(S):

The greatest benefit is driver compliance with work zone speed limits. This leads to smoother traffic flow and less speed variance within the work zone which in turn leads to fewer crashes.

MOST APPLICABLE LOCATION(S)/PROJECT(S):

Temporary speed limit reductions are targeted mainly for lane closure activities on freeways and Interstates with speed limits of 60 MPH and greater. The long term speed limit reductions are used on freeways and Interstates with speed limits of 60 MPH or greater that have significant lane geometry alternations and/or shoulder restrictions throughout the length of the project.

STATE(S) WHERE USED:

North Carolina

SOURCE/CONTACT(S):

Steve Kite, PE, State Work Zone Traffic Control Engineer, North Carolina DOT
Phone: (919) 662−4339
E−mail: skite@ncdot.gov