Complaints drive county to increase traffic studies

J. Craig Anderson

Monday, Feb. 13, 2006 | 12:31 p.m.

A year ago Clark County was as backed up with complaints about dangerous intersections as Las Vegas Boulevard is with traffic during rush hour.

To keep pace with the surge in requests for new traffic signals - prompted by growth and increased scrutiny of roadway safety efforts - the county's traffic management division in February 2005 accelerated its program of studying busy intersections and installing signals where needed, division manager John Toth said.

But reducing the number of crashes from the current daily average of 82 in Clark County and Las Vegas is not easy, he said.

Since the division was granted an additional budget of $1.4 million and the ability to hire outside traffic consultants a year ago, Toth said, it has studied 60 intersections, with another 24 studies in progress.

Nine intersections already have been approved for traffic signals, including Durango Drive and Blue Diamond Road, Valley View Boulevard and Sunset Road, Fort Apache and Russell roads, and Grand Canyon Drive and Desert Inn Road.

Another 19 signals approved earlier are in the bidding and construction phase.

On average, the division annually approves about 25 new traffic signals, each of which costs $300,000 - a price tag that often includes utility relocation expenses - and takes up to a year to install.

The increase in traffic studies performed may not result in more traffic signals, Toth said, but it has allowed for more frequent monitoring in high-growth areas and faster responses to residents' complaints.

While traffic volume is the leading factor in determining whether an intersection needs traffic signals, there is no single threshold number that gives a green light to a new signal, Toth said. Traffic flow and how many turns can be made at an intersection cause the required number to vary widely.

The traffic management division is unusually democratic in that it will conduct a traffic study - at a cost of $3,000 to $7,000 - on any intersection that receives a complaint, Toth said.

"Citizen requests are probably our leading determinant of where we study," he said.

Before the County Commission approved beefing up the traffic signal program, the division had a backlog of more than 40 requests, Toth said.

"We did not have the manpower to keep up," he added.

Another major factor in the decision to install traffic lights is an intersection's history of automobile collisions, Toth said, but all crashes are not created equal.

The only collisions that count toward warranting a traffic signal are those that could have been avoided by such a signal, he said. Wrecks involving drunken drivers, for example, do not count.

"There's a lot of art involved in the crash analysis," Toth said.

If five or more collisions considered preventable with a traffic signal occur within a year at an intersection, it is likely to receive a signal, he said.

Still, Toth said, traffic lights sometimes can create more crashes than they prevent, especially those involving aggressive driving at yellow lights.

In the end, it will take a combination of good traffic management and vigilant patrol officers to make Southern Nevada's streets safer, he said.

"Stricter enforcement is key," he said.

J. Craig Anderson can be reached at 259-2320 or at craig@lasvegassun.com.