Red or green, not all traffic signal timing treated equally
May 7, 2017 - 9:02 am
We’ve all sat at busy intersections, waiting for the traffic light to turn green.
Some streets seem to get more green time than others, which might seem unfair. In other instances, the preference goes to drivers making a left turn.
It’s a frustrating situation for motorists trying to predict a signal’s cycle, but not every intersection is treated equally.
Generally, there’s a method to the madness when it comes to traffic signal sequencing and timing, said Brian Hoeft, director of the Regional Transportation Commission of Southern Nevada’s traffic management center.
Hoeft oversees the engineers who control traffic signal timing across Clark County, while also monitoring traffic patterns captured on 600 cameras mounted on local freeways and streets.
Anita from Henderson wanted to know how drivers can predict which light will turn green first.
That all depends on where you’re driving, and when.
A combination of factors helps determine traffic signal timing, including pedestrian activity, street width and the average number of vehicles passing through an intersection on any given day, Hoeft said. Differences are broken down further during weekdays and weekends, along with morning and evening commutes.
Traffic engineers carefully study the information to decide when the priority should be given to motorists driving straight through an intersection, and when preference should be given to those making a left turn.
“This mainly has to do with moving platoons of vehicles through several consecutive green lights,” Hoeft said. “To make this happen, at one light we may need to run the left turn first, and sometimes we need to run it last to make everything fit.”
And then there are the cases when you might see a green light trigger for both a left turn and a straight lane on the same side of the street. Intersection geometry is factored in those instances, Hoeft said.
Grand plans for Grand Teton
Richard from Las Vegas wanted to know if any improvements are planned for Grand Teton Drive, between Fort Apache and Oso Blanca roads.
“It is narrow and lined with boulders,” Richard wrote in an email to the Road Warrior.
Las Vegas city officials are planning some pretty big improvements for Grand Teton, but you’re going to have to wait for a couple of years.
Designs are underway for an upgrade along Grand Teton between Fort Apache and El Capitan Way, including a bridge overpass at U.S. Highway 95, Las Vegas city spokeswoman Margaret Kurtz said.
The improvement plan was halted during the recession, but construction is expected to finally start in 2019 — if the money is allocated.
“We will need to evaluate next year what funds might be available for the construction,” Kurtz said.
Lane elimination not an option
Jerry from Henderson recently spotted a nasty car accident at Eastern Avenue and Pecos Ridge Parkway and observed it may have been caused by the configuration of the left turn pocket for drivers headed north at the intersection.
“During the morning rush hour, the left turn lane gets backed up and blocks the regular traffic lane,” Jerry said. “The left turn option should be eliminated for safer driving because accidents have happened here for a long time.”
Henderson city officials are drawing up plans to improve that intersection, but eliminating the left turn lane is not an option.
Plans call for lengthening the left-turn pocket from eastbound Pecos Ridge to northbound Eastern, Henderson city spokeswoman Kim Becker said. It’s unclear when the project will be completed.
Rough road
Paul from Las Vegas is among several readers who pointed out that the road is pretty rough along Maryland Parkway and on Paradise Road, between Twain and Tropicana avenues on the east end of the valley.
And, like a lot of us, Paul wants to know if Clark County plans to fix the problem.
County spokesman Dan Kulin said improvements are expected sometime next year for those sections of Maryland and Paradise.
Signal request will be studied
Nancy from Las Vegas wanted to know whether the county planned to install a traffic signal at Twain and Eastern avenues in the east valley.
Kulin said the county wasn’t planning on it, but traffic engineers will study whether a signal is needed at this intersection.
Questions and comments should be sent to roadwarrior@reviewjournal.com. Please include your phone number. Follow @RJroadwarrior on Twitter.
Road work ahead
Downtown
■ Martin Luther King Boulevard will be closed between U.S. Highway 95 and Bonanza Road from 7 p.m. Monday to 6 a.m. Tuesday. Crews are building new freeway bridge beams and decking.
■ Martin Luther King Boulevard offramps from northbound U.S. Highway 95 will be closed from 7 p.m. Monday to 6 a.m. Tuesday. Crews are building new freeway bridge beams and decking.
■ Bonanza Road is restricted between Main and Bruce streets until Friday. Crews are digging trenches and making sidewalk improvements.
■ Main Street is restricted between Bonneville Avenue and Las Vegas Boulevard through May 28. Crews are working on a storm drain.
■ Commerce Street is restricted between Wyoming Avenue and Main Street through May 30 for road improvements.
■ The northbound U.S. Highway 95 exit ramp to Rancho Drive will be closed through June 21 for work associated with Project Neon.
■ Martin Luther King Boulevard is closed between Oakey Boulevard and Interstate 15 through July. Crews are installing drainage boxes.
■ Oakey Boulevard is closed between Main and Commerce streets through July. Crews are installing underground utilities and storm drain infrastructure.
■ Washington Avenue is restricted between Martin Luther King Boulevard and Rancho Drive through Aug. 1. Crews are installing gas lines.
■ Ninth Street is closed between Carson Avenue and Main Street through Dec. 31 for sewer work.
■ U.S. Highway 95 will be restricted between Rancho Road and just east of Interstate 15 through January 2018. Crews are building a new flyover ramp for high-occupancy vehicles as part of Project Neon.
■ Sections of Bonneville Avenue, Charleston Boulevard, Grand Central Parkway and Martin Luther King Boulevard will have closed or disrupted lanes surrounding the Spaghetti Bowl as crews work on Project Neon through July 2018.
Resort corridor
■ Las Vegas Boulevard and Tropicana Avenue will be restricted from 10 p.m. Monday to 8 a.m. Tuesday. Crews are repaving the intersection within 300 feet of the pedestrian bridges.
East valley
■ Warm Springs Road onramp to westbound 215 Beltway will be closed until late May. Crews are working on a new bridge for the Airport Connector.
■ Nellis Boulevard will be restricted between Gowan and Craig roads through June 15. Crews are completing sewer work.
■ Las Vegas Boulevard will be restricted between Nellis Boulevard and Puebla Street through June 15. Crews are completing sewer work.
■ Warm Springs Road offramp from the eastbound 215 Beltway will be closed through June. Crews are building a new bridge over the highway.
Northwest
■ Farm Road is restricted south of Durango Drive through May 21. Crews are working on water and sewer lines.
■ Southbound U.S. Highway 95 will be restricted to one lane between Durango Drive and the 215 Beltway from 9 p.m. to 5 a.m. nightly through May 5. Crews are building a new flyover bridge.
Southwest
■ Rainbow Boulevard will be restricted in each direction between Hacienda Avenue and Sunset Road from 9 p.m. to 5 a.m. until mid-June. Crews are repaving the road and adding a traffic lane.
Summerlin
■ The northbound Buffalo Drive onramp to westbound Summerlin Parkway will close from 9 p.m. Monday to 6 a.m. Tuesday. Crews are repaving the ramp.
■ Summerlin Parkway's westbound off-ramp at Rampart Boulevard will close from 9 p.m. May Wednesday to 6 a.m. Thursday. Crews are repaving the ramp.
■ Westbound Summerlin Parkway will lose one traffic lane between Durango Drive and Rampart Boulevard for overnight work 9 p.m. to 6 a.m. Wednesday and Thursday. Crews are repaving the road.
■ The high-occupancy vehicle bridge linking northbound U.S. Highway 95 to westbound Summerlin Parkway will be closed until 6 a.m. Friday. Crews are repaving the bridge.
■ Summerlin Parkway's westbound off-ramp at Durango Drive will close from 9 p.m. Tuesday to 6 a.m. Wednesday. Crews are repaving the ramp.
■ Westbound Summerlin Parkway will lose one traffic lane between Buffalo Drive and Durango Drive from 9 p.m. Tuesday to 6 a.m. Wednesday. Crews are repaving the road.
■ Cliff Shadows Parkway is restricted at Novat Street through May 15. Crews are installing a traffic signal.
■ Summerlin Parkway's westbound lanes will be restricted between Buffalo Drive and Rampart Boulevard through July. Crews are building a new auxiliary lane and making other improvements.
■ The 13-mile scenic route at Red Rock Canyon National Conservation Area will be repaved in one-mile increments through summer.
Boulder City
■ U.S. Highway 93 will be restricted at U.S. Highway 95 in Boulder City from 7 a.m. to 2 p.m. Tuesday. Crews will repair a bridge joint.
Gasoline Prices
The average gasoline price Friday in the Las Vegas Valley was $2.66 per gallon. It was $2.68 in Nevada. The national average of $2.33 is down 6 cents from a week ago, down 5 cents from a month ago and up 11 cents from a year ago.
Las Vegas Review-Journal