New road signals to impact traffic flow

Instead of speeding up to merge onto the freeway, now some drivers will need to apply the brakes. Signals called ramp meters are scheduled to be activated at entrance ramps to U.S. Highway 95 and Interstate 515.

The signals are scheduled to go live March 29 on U.S. 95 at the Cheyenne Avenue and Lake Mead Boulevard on-ramps. Later this spring signals at the I-515 on-ramps at Fourth Street/Casino Center Drive, Las Vegas Boulevard and Eastern Avenue are set to be activated, as well.

Using red and green signals, the meters will allow only one car at a time to go down the entry ramp. It is hoped that such an approach will eliminate mass merging and the back-up it causes.

To trigger the ramp sensor, motorists need to pull up to the white stop bar on the pavement. The signal will change more rapidly than a regular traffic light. Drivers can proceed only when the light is green. The next driver in line gets a red light until the signal cycles back to green, usually in a matter of a few seconds.

At freeway entrance ramps with more than one travel lane, each will be controlled by its own ramp meter. Motorists are encouraged to use both lanes and to abide by the ramp meter signal controlling their lane of travel.

To keep traffic from backing up beyond the ramp, detectors will increase the signal cycle to allow cars to enter the freeway at a faster rate.

Ramp metering has proven effective in many cities nationwide, achieving reductions in freeway accidents and increasing freeway travel speeds. Traffic accidents were reduced in other cities implementing the system by 50 percent, according to information on the Regional Transportation Commission's Web site.

Robert H. McKenzie, public information officer with the Nevada Department of Transportation, said sensors have been installed over the past three years. The equipment measures traffic speed and volume on the freeway, and traffic demand on the ramp, to determine how quickly drivers can safely enter the freeway.

"We've been studying intelligent traffic systems for the last 10 years to determine the best kind for our city's needs," he said.

The system is intended to prevent many cars from trying to merge at once, which backs up traffic as the brakes are applied. Drivers on the freeway are forced to slow down to allow entry of cars from the ramp, resulting in sudden speed changes, backups and accidents.

California drivers are familiar with the system but Las Vegans greeted the news with mixed emotions.

"We need something like that because the freeway just gets too congested," said Gwenda Foy, a native who normally uses the Lake Mead Boulevard entry ramp on weekends. "It will give traffic time to settle down when it's real crowded."

Oddmund Mork of Sun City Summerlin said the merge ramp light is "a good thing. It's a good thing to have a stop light there. There are too many accidents."

Ramp meters will operate only when the freeway is congested, usually during morning and evening peak commute times. Motorcycles will be allowed to use a bypass lane without stopping. So will high-occupancy vehicles carrying two or more people.

Ingrid Reisman, communications manager for the Regional Transportation Commission of Southern Nevada, said ramp meters throughout have helped communities better manage significant congestion.

"We want to get commuters used to using the system and working with it on a daily basis," Reisman added. "More ramp meters will be installed as construction continues and roadways improve."

Police warn that failure to stop at a ramp meter when it is red is a traffic violation similar to running a red light, and can result in a fine.

For comments or questions about ramp meters, call the RTC's hot line at 385-7267.