Newly Timed Traffic Signals Save Motorists Money

December 21, 2008 - From SourceNewspapers.com

Motorists driving on Mound Road have been saving time and money without knowing it for the past two years, thanks to the Road Commission of Macomb County.

When totaled together, the 70,000 motorists who use Mound daily have saved approximately $2 million in gasoline costs since a high-tech computerized system of controlling the timing of traffic signals along the 12-mile corridor, from 8 Mile Road to M-59, went into operation in 2006 to move vehicles more safely and efficiently.

“Under the right traffic conditions, if you drive the speed limit of 50 miles an hour, it is possible to be able to make every light on green through Warren and Sterling Heights,” said Adam Merchant, traffic engineer for the RCMC. “That saves time, money and gasoline and it’s good for the environment. The less time your car is idling at a traffic signal reduces the amount of tailpipe pollution going into the air.”

There are some caveats to making all - or most all - of the lights and in driving the route, it is easy to spot them. They include slow drivers, the amount of traffic on the road, the length of the lineups at the traffic signals, how quickly motorists start up when the light turns green and the speed of the traffic.

Still, the lights are timed to maximize the traffic flow.

“To the individual motorist it may not seem like a lot, but when you add up the savings in time, money and wear on your automobile, there are measurable benefits,” he said.

An analysis of the Signal Optimization project by Parsons Brinckerhoff Michigan Inc., in Detroit, found:

• Before the Signal Optimization during the afternoon rush hours it took cars an average of 1,162 seconds -- or 19 minutes and 36 seconds -- to go northbound on Mound from Interstate 696 to M-59, a distance of about nine miles.
• After the signals were retimed specifically for the rush hour, it took motorists an average 869 seconds -- or 14 minutes and 48 seconds -- to get from I-696 to M-59. That’s a reduction in time of 4 minutes and 48 seconds.

Other findings by Parsons Brinckerhoff, which analyzed Mound’s traffic counts and patterns, and used the data to optimize the signal timings on Mound are that:

• It saves motorists a total of 67 million minutes or approximately 1.12 million hours each year.
• It saves motorists approximately $1 million -- or around 495,000 gallons in gasoline and diesel fuel -- a year based on fuel costs of $2 a gallon. However, fuel prices have been much higher during the past two years and were more than $4 a gallon last summer, so the savings have been greater.

There are four different signal timing plans running the switching of the traffic lights on Mound now. They run the traffic signals during the morning rush hours, afternoon rush hours, off-peak hours and plant shift changes. While they all provide savings in time and money for motorists over the previous system, the most dramatic is the northbound afternoon rush hour program.

“But if it’s only 60 seconds - one minute - less that it takes someone to get from I-696 to M-59, when you multiply that times the 70,000 cars that use the road daily, that would be 70,000 minutes saved. That’s a lot of time and fuel savings for people,” said Road Commissioner Bob Sawicki.

“We would be remiss if we didn’t expand this program to other main roads when we have the opportunity and funding,” Sawicki continued, adding that within the next year the road commission will install the optimized signal timing in other high-traffic corridors.

During the next year, the road commission will spend approximately $750,000 it obtained from federal highway grants to analyze traffic patterns on the following roads, develop the timing programs to operate the signals to maximize traffic flow and install them, Sawicki said.

Those roads are:

• Schoenherr Road from 8 Mile Road to 23 Mile Road
• Garfield Road from Utica Road to 21 Mile Road
• Hayes Road from Utica Road to M-59
• Metropolitan Parkway from Dequindre Road to Jefferson Avenue
• Harper Avenue from 8 Mile Road to Metropolitan Parkway

Another benefit of the Signal Optimization project on Mound is that by moving traffic more efficiently, it reduces the need for more lanes of roadway to handle the traffic.

That means less construction disruptions for motorists, local residents and businesses, and a savings to the taxpayers who ultimately pay the road building costs, Sawicki said.

He noted that one mile of concrete pavement can cost approximately $5 million, provided there is room for it and the right-of-way can be obtained. Whereas, changing the signals on Mound to get the maximum use of it to daily move the 70,000 vehicles most efficiently only costs $250,000, which came from a federal grant.