In a highway construction zone when a lower speed limit is posted but no workers are present or visible impairment is evident, the lower speed limit looses credibility. Drivers perceive no good reason for slowing down and tend to maintain their speed.
Highway 59 in East Texas is a long term construction project and re-quires a source of reliable information. ELTEC (Electrotechnics Corp) along with the TxDOT office in Atlanta (TX), A-T Communications and the Texas Transportation Institute, developed a solar powered Work Zone Speed System which displays selected speed limits for the appropriate conditions.
When workers are present or hazardous conditions exist, the lighted speed display sign is manually changed by responsible personnel to display the lower speed. It can also be changed by wireless radio. When it’s safe for motorists to drive the normal speed (70 MPH), the sign indicates accordingly. In Texas speeds are reduced at night, so at dusk the system automatically switches to the lower speed of 65 MPH unless the ‘construction zone’ switch is activated and overrides the day/night speed displaying the lower construction speed. The work zone speed is adjustable and set prior to deployment.
The Work Zone Traffic Speed System can be trailer mounted for portability. If the shoulder is too narrow/steep or a more permanent system is required/desired it can be pad mounted as with the four TxDOT units.