Why Are There Speed Limits?
Speed regulations and speed limits are intended to supplement motorists' judgment in determining speeds that are reasonable and proper for particular weather and road conditions. Limits are imposed to assist enforcement personnel and to promote better traffic flow by reducing the wide variance in speeds.
Who Sets These Limits?
Virginia's General Assembly has granted authority to the commonwealth transportation commissioner, who heads the Virginia Department of Transportation (VDOT), and to cities and certain counties and towns to establish speed limits that do not exceed the maximum allowed by law for highways under their jurisdictions.
The General Assembly retains authority for establishing statewide maximum limits.
How Are Speed Limits Determined?
Factors considered in determining reasonable and safe speed limits are categorized into two phases: the engineering investigation and the traffic investigation.
The engineering investigation involves a study of the geometric design of the road. Engineers review such items as:
- Lane width
- Pavement type and condition
Engineers also look at:
- Parking conditions
- Commercial and residential development along the road
- The number, width and types of entrances and intersecting streets
The traffic investigation involves gathering and analyzing traffic-related data. Engineers study:
- Prevailing vehicle speeds
- Average test runs
- Traffic volumes
- Accident experience
- Traffic control devices that affect or are affected by vehicle speeds
Federal legislation enacted in 1995 gave individual states the authority to establish their own maximum speed limits. Prior to the 1995 law, federal law required that the maximum speed limits on interstate highways be 65 mph for rural interstates and 55 mph for urban interstates.
For the most part, Virginia has chosen to follow those guidelines.
Why are only some Interstate Speed Limits 70 mph?
Although a change in state law effective July 1, 2010 increased the maximum allowable highway speed limit to 70 mph on interstates and certain other highways the law requires that a traffic engineering study first be conducted. Engineering studies conducted subsequent to the change in law identified some 671 miles of rural interstates statewide that were appropriate for 70 mph. Generally, the sections of interstate that were deemed appropriate for an increase to 70 mph were rural highways already posted at 65 mph where the prevailing vehicle speeds were 70 mph with minimal congestion and low safety risk. Sections of Interstates within and approaching urban areas were generally not considered viable for a 70 mph speed limit..
What Are The Speed Limits For Roads That Are Not Posted?
The speed limit for most business and residential areas is 25 mph. On secondary roads (those routes numbered 600 and above, with one exception), the limits are 45 mph for trucks and 55 mph for other vehicles.
How Can I Get Motorists To Slow Down In My Neighborhood?
Many people assume that reducing a speed limit will cause speeding motorists to slow down, but studies have shown that this is not the case.
When determining speed limits, engineers attempt to set a realistic limit that the majority of drivers will obey and that can be reasonably enforced. Contact the state police or your local police if motorists are traveling at speeds higher than what is posted.
How Can I Get A Speed Limit Lowered Or Raised?
If you feel there is a need to change a current speed limit or if you have other questions, contact the resident maintenance manager at your local VDOT office.
How Can I Get More Information?
For more details about speed limits, consult the Virginia Driver's Manual published by the Virginia Department of Motor Vehicles.
This information is not intended to replace the laws of Virginia relating to speed limits. For specific questions, refer to Chapters 46.2-870 through 46.2-878 and 46.2-1300 of the Code of Virginia (1950) as amended.