If you have traveled along W. Broad Street in Henrico County lately, you may have noticed that the aging span wire traffic signals are being replaced with new signal heads and poles. The signal upgrades are being constructed by VDOT with funding provided through the Highway Safety Improvement Program (HSIP). HSIP is a Federal-aid program that exists to reduce traffic fatalities and injuries on all public streets and highways.
One example of a HSIP funded project that was designed by Timmons Group for VDOT is located at the W. Broad Street and Bethlehem Road intersection in Henrico. The project involved removing the old span wire mounted traffic signals and replacing them with new mast arm mounted LED traffic signals and street name signs with larger text to meet the current Federal standards.
The advantages of LED signals include: brighter lights, consuming only 10 percent the electricity used by incandescent bulbs, and they have a long life that can lasts for 7 to 10 years. So how do the advantages of LED signals translate to an increase in safety?
1.) Avoids the Phantom Effect. Incandescent signals have reflectors behind the bulbs and on east-west approaches during morning or evening, all colors appear to be on when the sun light is shining directly on the signal lens. This problem is eliminated when LED signals are installed because reflectors are not used in LED signals.
2.) Contains a battery backup system. When there is a loss of electricity during a storm event, the LED low power requirements allow the signals to continue operating on a battery back-up system for up to 24 hours (depending on the signal configuration) before replacing the batteries.
3.) Less Maintenance. The incandescent light has only one filament that requires immediate replacement when it fails. The LED signal contains several dozen miniature diodes and will continue to function even when some of the diodes stop working. The long life-span of the LED signal means less demand for an agency’s maintenance staff to be working in the middle of the intersection to change a light bulb.
Other safety improvements for this project included installing new curb-cut ramps, completing sidewalk networks surrounding the intersection, new traffic detection zones, and stop line adjustments to improve the turning path for vehicles making left turns. Signal preemption equipment was also added to allow for emergency vehicles to interrupt the normal signal operation and proceed through the intersection with less delay and under safer conditions.
Timmons Group provided VDOT all the engineering services necessary to successfully complete this HSIP project, and many other safety projects, while staying on schedule and within budget.
Contact Danny Lamie at danny.lamie@timmons.com for more information about the professional services Timmons Group can provide for your next traffic safety improvement project.
