It’s all about the timing for traffic signals in Las Vegas
July 22, 2018 - 5:16 pm
Traffic signals seem to take an awfully long time to change at some of the busiest intersections across the Las Vegas Valley.
Some streets get more “green time” than others. A few left-turn signals allow only a few vehicles to pass at a given time. Frustration often ensues.
A few of you have asked how traffic signals work, and what exactly triggers that green light?
Usually, it’s all about timing, according to Catherine Lu, a spokeswoman for the Regional Transportation Commission of Southern Nevada.
“The timing of traffic signals across the valley are pre-programmed based on the time of day, the day of the week and travel demand at intersection locations,” Lu said.
Of course, signal timing may be adjusted with the following exceptions:
■ Video detection, magnetic loops embedded in the road’s pavement, infrared technology and other sensors can detect vehicle flows, resulting in a longer green light to keep traffic running smoothly.
■ Pedestrians who trigger the “walk” signal at busy intersections, which usually leads to an extended green light for vehicles traveling in the same direction, allowing enough time for the pedestrian to safely get across the street.
■ Fire trucks, police cruisers and other public-sector emergency response vehicles are equipped with special sensors that communicate with traffic signals, allowing for a green light as first responders approach the intersection.
Drivers who spot problems with traffic signals or have concerns about timing can file a report with the RTC’s “Seeing Orange” campaign at 702-928-2663 or seeingorangenv.com.
Road blocked by sewer work
Peggy from Las Vegas wanted to know when road construction will wrap up on Stewart Avenue between Mojave and Sandhill roads just east of downtown.
Construction started in May on a sewer rehabilitation project along Stewart, resulting in the loss of some traffic lanes in between Sandhill and U.S. Highway 95, Las Vegas city spokeswoman Margaret Kurtz said. The work is expected to wrap up in January.
“Although it may appear that there is no work occurring at the street level, the sewer bypass is active in this area so we are able to proceed with our underground pipe lining project,” Kurtz said.
Limit lines disappearing
Jay from Las Vegas noticed that the white limit lines have pretty much disappeared on the westbound Spring Mountain Road onramps and offramps at Interstate 15 in Spring Valley.
Without the limit lines, Jay noted that “people can accidentally end up in the middle of the intersection.”
Tony Illia, a spokesman for the Nevada Department of Transportation, said that road crews will take a look and make the necessary improvements to keep the intersection safe.
Yield arrows not allowed here
Stacy from Henderson wanted to know why the city won’t install a flashing yellow left-turn arrow that would allow drivers to yield before turning left from westbound Horizon Ridge Parkway onto Stephanie Street.
Kathleen Richards, a spokeswoman for the city of Henderson, said that the intersection’s configuration with dual-left turn lanes makes it difficult for motorists to see and yield for oncoming traffic. Dual left-turn lanes typically have protected arrows, while the flashing yellow arrows are reserved for single left-turn lanes.
Slow-paced Silverado Ranch Road
Glen wanted to know why the speed limit is 35 mph along Silverado Ranch Road between Interstate 15 and Decatur Boulevard in the southwest end of the valley. With few houses and empty lots, Glen believes motorists should be allowed to drive faster on this stretch of road.
“With all that open space, why was only one lane built in each direction with a large center lane?” Glen asked.
Clark County spokesman Dan Kulin said the speed limit will be reviewed in 2020, when county officials start designing a series of road improvements for a larger section of Silverado Ranch between Dean Martin Road and Jones Boulevard.
Left-turn signal coming soon
Don from Las Vegas wanted to know whether county officials plan to install a left-turn signal for drivers on McLeod Drive who are waiting to turn left onto Flamingo Road.
“Right now, traffic backs up because there is not a protected arrow to make the turn, and it’s a long cycle to wait for,” Don said.
Kulin, the county spokesman, said a set of flashing yellow left-turn arrows are planned for Flamingo and McLeod, but it was unclear when those special signals will be installed.
Questions and comments should be sent to roadwarrior@reviewjournal.com. Please include your phone number. Follow @RJroadwarrior on Twitter.
Road work ahead
Downtown
— Ogden Avenue will be restricted between Main Street and City Parkway through mid-October. Crews are making street, sidewalk and lighting improvements.
— The Charleston Boulevard onramps to southbound Interstate 15 are closed until mid-October. Crews are rebuilding the intersection.
— The D Street offramp from northbound Interstate 15 is closed through mid-November. Crews are widening the freeway.
— Interstate 15 will be narrowed in both directions between Sahara Avenue and D Street until Nov. 20. Crews are widening the freeway.
— The ramp connecting southbound U.S. Highway 95 to southbound I-15 will be reduced to one lane and detoured through Nov. 20. Crews are widening I-15.
— The ramp linking southbound U.S. 95 to northbound I-15 is closed through Nov. 20. Crews are widening I-15.
— The Martin Luther King Boulevard onramp to southbound U.S. Highway 95 is closed until early 2019. Crews are building a high-occupancy flyover ramp.
— Gass Avenue will be restricted between Las Vegas and Charleston Boulevards through March 2019. Crews are making pedestrians and bicycle improvements.
Northwest
— Buffalo Drive is restricted between Gowan Road and Cheyenne Avenue through July. Crews are upgrading a gas line.
— Tenaya Way and Torrey Pines Drive are restricted between Gowan and Craig roads through July. Crews are upgrading a gas line.
— Gowan Road is restricted between Buffalo and Torrey Pines drives through July. Crews are upgrading a gas line.
— Craig Road is restricted between Torrey Pines Drive and Decatur Boulevard through July. Crews are upgrading a gas line.
— Both directions of U.S. Highway 95 will be narrowed to two lanes at Elkhorn Road through December. Crews are building a new carpool ramp.
Summerlin
— Summerlin Parkway is restricted between Durango Drive and the 215 Beltway through the end of July. Crews are paving the road.
East valley
— Both directions of Charleston Boulevard will be restricted between U.S. Highway 95 and Marion Drive through Aug. 3. Crews are rehabilitating a sewer line and manholes.
North Las Vegas
— Ramps and travels lanes at Interstate 15 and U.S. Highway 93 will be restricted intermittently from 7 p.m. to 7 a.m. nightly through Wednesday. Crews are reconfiguring the freeway interchange.
— Nellis Boulevard is restricted between Cheyenne Avenue and Las Vegas Boulevard from 6 a.m. to 3:30 p.m. weekdays through July. Crews are installing sewer pipes.
Henderson
— Stephanie Street will be restricted between the 215 Beltway and Cielo Abierto Way through October. Crews are repaving the road and making other improvements.
Gasoline prices
The average gasoline price Friday in the Las Vegas Valley was $3.12 per gallon. It was $3.18 in Nevada. The national average of $2.84 is down 4 cents from a week ago, down 3 cents from a month ago and up 56 cents from a year ago.