Staying ahead of the traffic swell

Study indicates bypass would be better than signal

An estimated 2,000 trucks per day are expected to be lumbering up U.S. Highway 93 through Hemenway Valley after the Colorado Bridge is completed, but the Nevada Department of Transportation claims that conditions, based on any one of eight warrants, would not justify a signal, even with the new traffic. According to a traffic study done by Stantec Consulting, left turns out of Lake View Estates from Temple Rock Road, with the expected traffic increase on U.S. Highway 93, would take more than 1,000 seconds (nearly 17 minutes) if there were raised medians, but only 64 seconds if a signal was installed. Photos / Fred Couzens/VIEW Advertisement

When it comes to the projected gridlock on U.S. Highway 93 that's expected to creep through Boulder City after the Colorado River Bridge is completed, the city is finding itself between a rock and a hard place.

On one hand, the city knows that residents on both sides of Hemenway Valley will still find it difficult to maneuver onto the highway even with raised medians and lengthened merge lanes -- control measures that exist today, but only with paint and tape.

On the other hand, though, a consultant's study, which is fodder for any Nevada Department of Transportation determination, claims that even with "traffic loading failures," "deteriorating traffic operations," and underestimated traffic counts, that traffic control devices -- signals or interchanges -- are not needed. Instead, the best solution is "an alternative route like the Boulder City Bypass."

The Transportation Department's best estimates put the opening of the 12-mile, $400-million bypass nearly 20 years away while increased traffic from the new bridge -- as many as 25,000 additional vehicles per day on top of about 16,000 today -- will be dumped into Hemenway Valley at least 15 years sooner.

Despite the frustration, the city hasn't thrown in the towel.

"People might think we're not doing anything, but we're not giving up," City Manager Vicki Mayes said. "We'll continue to plead our case to the state. It's just that NDOT has a different goal. They said they would re-evaluate the situation and address alternatives when (the traffic) became an issue. What we're trying to do is be pro-active, but that's not the way they do business."

The Transportation Department's decision to use only minor measures to mitigate the dreaded continuous stream of traffic in both directions on U.S. 93 is rooted in the Stantec study, which uses the Federal Highway Administration's "Manual on Uniform Traffic Control Devices" that has become the standard nationwide for making traffic engineering decisions.

To qualify for consideration of a traffic control device, like a signal, the intersection in question must meet one of eight warrants.

Those warrants are eight-hour vehicular volume, four-hour vehicular volume, peak hour, pedestrian volume, school crossing, coordinated signal system, crash experience, and roadway network.

The MUTCD chapter on Traffic Control Signal Needs Studies specifically states, "A traffic control signal should not be installed unless an engineering study indicates installing a traffic control signal will improve overall safety and/or operation of the intersection" and "... if it will seriously disrupt progressive traffic flow."

In the first case, Stantec determined overall safety and operation of the four intersections in the Hemenway Valley area -- Lakeview Drive, Lake Mountain Drive/Nevada Way, Ville Drive and Pacifica Way/Temple Rock Road -- would not be improved because of the low traffic counts on the minor streets entering the highway.

The study admits there will be delays, even major delays at some intersections, but there are not any safety problems foreseen.

Despite the hordes of vehicles projected for U.S. 93, it's the low traffic counts on the streets leading from the residential areas that prevent a warrant for a signal.

"We don't have enough traffic on the side streets," City Engineer Jim Keane said. "Yes, the volume is there on the highway, but it's the side streets that aren't meeting the volume warrants."

Keane said the city could install traffic signals at its own cost on the highway, but that the state would have to approve it.

"The state's not going to approve that," Public Works Director Scott Hansen said. "And we can't overturn NDOT's decision."

The Transportation Department's decision, as outlined by Boulder City Bypass project manager Glenn Petrenko at a Feb. 20 informational meeting, is to spend about $1 million for the roadway improvements in Hemenway Valley during Phase 1 bypass construction -- still at least three years away -- in lieu of any other improvements.

"There was a speed study done from Buchanan to Ville and there were no warrants for lights and you need one to consider a light," Petrenko told an agitated crowd of about 50 residents who want to see a better state response to the looming gridlock that even the consultants admit is going to happen. "We'll continue to monitor the situation though."

Even Hansen, who's been in on conversations with the Transportation Department, is not particularly pleased with the solution the department has etched in concrete.

"Maybe (drivers) will feel a little safer with the median raised up, sort of like a little curb to protect them," he said. "I envision that area to be like Tropicana Boulevard behind the Strip and I think the business corridor is going to have some real impacts there."

There are downsides to installing a signal.

"On the pro side, a signal organizes traffic, reduces delay on minor streets, reduces left-turn accidents and allows for better coordination of signals elsewhere in the right of way," Keane said. "On the con side, it sometimes can increase the delay on major streets, it can increase rear-end accidents, there's a cost to maintain the signals, and it can reduce or slow down truck uphill movements like what we find at Railroad Pass today."

The city does have some potential tricks up its municipal sleeve.

Mayes mentioned the possibility of a different alternative route behind Lake Mountain Drive so people could "get outside the city."

Keane discussed the term "engineering judgment," a subjective tool used by traffic engineers to find a solution for a problem when the conditions are real yet they don't adhere to any of the eight traffic warrants.

But Keane said the major potential surprise comes from the FHWA's manual itself. It states under "Roadway Network" a signal shall be considered if "the intersection (of two or more major routes) has a total existing or immediately projected entering volume of at least 1,000 vehicles per hour for each of any five hours of a non-normal business day (Saturday or Sunday)."

As it is today, under the federal definition of "major route," only Nevada Way meets the definition because it is not residential in nature, but does serve as a business bypass route for U.S. 93.

As of 2008, car and truck traffic is projected to exceed 20,000 vehicles per day, or 833 per hour, which would exceed 1,000 per weekend day due to Lake Mead traffic.

With more than 20,000 additional vehicles per day projected to be commuting from the planned developments in Northern Arizona to the Las Vegas Valley within the next decade, the numbers make the Nevada Way/U.S. 93 intersection a prime candidate for consideration of a traffic signal.

However, the Stantec study gives that option a low ranking, citing the impacts of increased traffic noise on nearby residents as the main reason for its low marks.

Nevertheless, all agree that the conditions are going to get worse before they get any better and that once the Colorado River Bridge opens, everyone's eyes will be on the traffic, with further mitigation measures a real possibility.

Boulder City residents will get another chance to hear the Transportation Department's presentation on the bypass and its associated effects at next week's City Council meeting.