Traffic cams speeding up commuters in the metro

New state-of-the-art traffic cameras aren't capturing photos of speedy Des Moines-area motorists but instead are helping move commuters along in an effort to reduce traffic snarls on heavily traveled thoroughfares.

West Des Moines, which in 2010 installed Iowa's first traffic-adaptable signal, has nearly 50 of the cameras and next year, the city plans to activate more along the University Avenue corridor west of 22nd Street. Other cities also have plans to add the cameras, including Des Moines.

"Travel speeds are up, delay is reduced and number of stops are reduced," West Des Moines Traffic Engineer Jim Dickinson said of the cameras, "and we're seeing some reductions in crashes."

The cameras, located at major intersections, constantly observe and assess traffic flow and respond in real time to congestion. The cameras detect when traffic is backed up at an intersection and its sophisticated computer program changes the lights to get vehicles moving.

Traffic studies were done along Jordan Creek Parkway — West Des Moines' busiest corridor with more than 30,000 vehicles traveling daily — before and after adaptive signals were installed at nine intersections last summer.

The system eliminated 56 percent of the stops for the average vehicle and reduced travel time by 24 percent, the studies showed. The numbers add up to 242 hours a day of reduced travel time and roughly 159 gallons of daily gas savings.

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Five West Des Moines traffic-adaptive projects have been paid for with money mostly from Iowa's Clean Air Attainment Program.

The 18 adaptive traffic signals that will be installed next year on University Avenue — more than any other corridor — will cost $615,000. The clean air program is contributing 80 percent of the funds; Clive and Waukee are also helping to pay for the lights.

The system is expected to go live in the spring, bringing reprieve to tens of thousands of people like Teresa Bjork, who has traveled to Iowa Farm Bureau headquarters, 5400 University Ave., for 15 years.

"It's pretty bad," said Bjork, who daily drives University west of the Interstate Highway 80/35 exit.

"It's really just like two blocks, but I have to be on high alert for those two blocks. And I have to sit on the ramp for quite a while, five minutes or more, just to get onto University."

Bjork said the congested stretch is the main reason her weekday drive from Madrid averages 35 to 40 minutes compared to 25 minutes on the weekend.

"You can just see this huge line of cars going from west to east on University," she said, noting that traffic signals seem frequently out of sync.

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Nathan Goldberg, senior transportation planner with Des Moines Area Metropolitan Planning Organization, said he recommends adaptive signals as the first step to relief on congested corridors.

"These types of solutions should be considered and implemented before road widening and other more expensive tactics," he said.

Officials with the company that designs the system implemented in West Des Moines, Rhythm Engineering, said they have adaptive signals across 100 U.S. cities in 27 states since starting in 2008.

"We're turning on two traffic corridors a week somewhere in the United States," said Reggie Chandra, president and CEO of Rhythm Engineering. "Every year we've grown and this year we will be doubling."

Some of the cities that are adding the cameras are in central Iowa.

Clive has applied for an ICAAP grant that could pay for 80 percent of an adaptive system, with 15 intersections along Hickman Road/U.S. Highway 6.

If approved, the project is expected to be completed in 2016.

Des Moines could also see its first adaptive system by 2015 on Southeast 14th Street/U.S. Highway 69, City Traffic Engineer Jennifer McCoy said.

McCoy said a study with the Iowa Department of Transportation is underway to confirm whether adaptive signals are the best measure to improve traffic safety between Southridge Mall and Maury Street, just north of the Des Moines River.

"The DOT actually approached us on it as part of their efforts to improve safety statewide," McCoy said.

The new systems are replacing stoplights that are programmed to a set clock based on previous traffic studies, many of which are outdated, Dickinson said.

Traffic engineers can tweak the preset programming or manually override them at any moment from a traffic control room. But neither option can compete with the intelligent adaptive system, said Traffic Group Leader with Snyder & Associates Mark Perington.

"Every day, every hour, every minute it is sampling traffic," Perington said. "Adaptive is kind of the next wave of (traffic) technology."

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HOW ADAPTIVE SIGNALS WORK

Installing an adaptive traffic signal is like placing a human at an intersection to control stoplights in response to live traffic flow, officials said.

With a network of signals, connected via fiber optic cables along a corridor, the adaptive systems are replacing older traffic lights that are limited by pre-programmed timers and patterns based on individual traffic studies, according to experts.

"Video cameras form the eyes, so they know how many cars are waiting, how long they've been waiting and they communicate with traffic signals down the line," said Reggie Chandra, president and CEOof Rhythm Engineering, which designed and manufactures InSync traffic control system.

The system can keep drivers on their toes because it changes the signal based on immediate demand in any one direction rather than cycling through each side of the intersection in order.

It brings various benefits to primary corridors during all times of the day. For instance, it creates solid green lights late at night, only changing when the occasional vehicle on a side street approaches, officials said.

The signals can also relieve some headaches for city traffic engineers like West Des Moines' Jim Dickinson, who often manually control signals from a traffic control room (watching major intersections from monitors) in unusual circumstances or near high-congestion areas during rush hour.

"Sometimes I have to make the decision, 'What street do I want to make a parking lot,' " Dickinson said.