Induced demand: alternatives to toll roads

April 3 – As the Oklahoma Turnpike Authority moves forward with a statewide expansion of toll roads, transportation experts say new roads can increase congestion while other alternatives reduce it.

The OTA announced plans in February to build two new toll roads in Norman – one along Indian Hills Road to connect Moore, Norman and Oklahoma City, and a second to extend the Kickapoo Turnpike across Interstate 40. south through eastern Norman, west of Lake Thunderbird to Purcell.

Civil engineers, academics, and transportation organizations affirm the basic law of traffic congestion, or induced demand — — more road capacity or additional roads leads to more traffic, and therefore more congestion over time.

It’s a law that OTA deputy director and chief engineer Joe Echelle said he didn’t know during a city council study session on Tuesday night.

Scale was unable to provide an interview with The Transcript by Friday.

Induced demand

The law of induced demand dates back to the 1960s and over the years has been affirmed by universities, civil engineers, policy think tanks and other transportation organizations.

The Transportation Research Board calls the evidence for induced demand “strong” and found that it is often “overlooked, underestimated, or misjudged in the planning process,” according to its 2020 report, Induced Vehicle Travel in the Environmental Review Process.

“Underestimating the induced trips will generally result in an overestimate of the traffic congestion reduction benefits that a freeway expansion project could generate, as well as an underestimate of its environmental impacts,” the report states.

A new road can attract housing development and businesses, which over time creates more traffic and congestion that was once a smooth bypass, says Dr. Asha Weinstein Agrawal, professor of urban and regional planning at the San Jose State University in California, where she attends the Mineta Transportation Institute.

“If you build a new highway and it’s not congested, all those people who weren’t driving don’t travel that particular distance [will] saying ‘oh I can drive this way now’ or people are moving to live along this highway because it used to be so congested, but now there’s a highway,” Weinstein Agrawal said.

“Traffic comes back as long as your economy is strong and there aren’t other forces encouraging people not to drive more,” she said.

At best, one researcher says expanding highway capacity is a “bad strategy” but fails to “summaryly dismiss” it as a policy option, a 2018 paper on transport policy, “If You Build It They’ll Drive” by Kent Hymel reads.

Supply and demand

Build it or not, more traffic is coming, according to Scale. He reported to the board Tuesday that the OTA predicted I-35 traffic would double in 30 years and said Texas plans to expand I-35.

The transcript secured the Texas Department of Transportation’s 2040 plan, which calls for widening I-35 from four to six lanes south of US-82 to Exit 1 in Oklahoma and four eight-lane south of US-82 to the Red River Bridge. at the Oklahoma state line.

“It’s impossible for traffic to double on I-35 with this current configuration without being bumper-to-bumper all day, every day,” Echelle told the board.

Echelle said that since the population is expected to increase, especially around Goldsby and Purcell, the area will need a relief road.

During rush hour, it takes the driver 87 minutes to get from Purcell to “the north end of the Kickapoo Turnpike if you stay on I-35 to the Turner (Turnpike),” Scale said. “If we don’t do something, if we don’t provide some kind of relief for this by 2050, just 30 years into the future, this journey will go from an hour and a half to two hours and 10 minutes on the road and that will last more of the day than it does now.”

Where there are traffic jams, there is an increase in accidents, and Echelle said it will get worse. He presented a chart showing traffic collisions on I-35 from Purcell to I-40 hit an all-time high, rising from 504 in 2012 to 1,827 in 2019.

Most of the crashes were two vehicle collisions – nearly 4,000 people affected, he said.

If it’s not a toll road, then what?

Some states have deviated from building new toll highways and adopted modifications to existing roads, such as designated lanes for carpoolers, toll lanes or trucks.

Weinstein Agrawal said that while these options aren’t always popular or perfect, they are alternatives to building more highways.

“When a lane is sort of free flowing, more cars or trucks can pass in a given amount of time and then everyone backs up and it slows down,” she said. “There are studies that show that if you take a path [as a toll lane], the other lanes might be better off in the short term, if enough people are willing to pay the toll. If they go out of the free lane then you might actually have free speeds on the free lanes and that argument is often made long term if traffic is an issue.”

The high-occupancy toll lanes are also used to operate express bus services like San Diego’s, Weinstein Agrawal said. “This means you can offer a bus trip so you don’t get stuck in traffic as an alternative.”

The price is right

Another option is congestion pricing, which charges drivers different prices at different times of the day to deter congestion, from lower prices at low peak times to higher prices at peak times. A higher price deters drivers from using a congested lane or highway.

While congestion pricing can be limited to location and times of day, some congestion pricing technologies read the speed on the freeway and set a new signage price alert to drivers.

“They’ll have variable message signs, so you’ll know if you want to get into the HOT lane for the next 10 miles, it’ll cost you $4. As long as you allow the tolls to go up high enough, they do. Everyone won’t don’t like them, but they work. Eventually, enough people are saying, ‘I’m not paying for this,'” Weinstein Agrawal said.

Oklahoma charges lower toll fees than the national average to bleed travelers off the freeway and onto the toll road to relieve congestion, an OTA presentation showed Tuesday. Cars pay less than 10 cents per mile compared to the national average of 20 cents, and trucks pay less than 25 cents per mile when the national average is nearly 80 cents per mile.

The newspaper asked the Oklahoma Department of Transportation to list other options it has considered to ease congestion. ODOT spokeswoman Brenda Perry Clark said the department has determined that high-occupancy toll lanes will not relieve congestion on I-35, nor will the freeway widening.

“Widening I-35 beyond the recently completed 6-lane effort from downtown Oklahoma City to the North Canadian River has taken more than three decades,” she said in an email Friday. . “Additional right-of-way and continued disruptions will not be possible in this corridor, requiring a back-up route. Even an expanded facility would not remove through-truck traffic from the corridor and would force the continued mixing of traffic from commuter and freight on the burgeoning facility.As such, it was necessary for OTA to use their backhaul capabilities to generate the necessary funds to complete the necessary relief route.

Congestion pricing results elsewhere

Congestion pricing has been hailed as a success in other cities around the world, including London. England’s most congested city has studied congestion pricing in Singapore. The Center for Public Impact reported in 2016 that London’s traffic pricing experiment reduced congestion by 26% in 2006 compared to levels recorded in 2002.

According to a 2018 Bloomberg article, “London’s congestion charge is showing its age”, the program’s success has clouded as cars exempt from paying the toll soared 75% between 2013 and 2017, but the area is easing always congestion.

Other cities like Chicago are turning to congestion pricing. The Chicago Metropolitan Agency for Planning cited Singapore’s successful model in September as it assessed transportation improvements.

“Electronic road pricing has reduced traffic in the restricted area and led to more reliable journey times,” CMAP said on its website. “By combining congestion pricing with investments in transit, cycling and walking networks, and transit-oriented development, Singapore has increased bus and rail ridership and reduced carbon emissions. greenhouse gases in the city center.

Singapore traffic delays in ‘restricted areas’ plummeted as speeds increased ‘20% or more’ during peak hours and on the most congested roads speed increased 30% from 15 to 18 %,” the U.S. Department of Transportation noted.

According to, other cities that use some form of congestion pricing include Milan, Italy; Stockholm; Riga, Latvia; Znojmo, Czech Republic; Valletta, Malta; San Diego and Miami.

Mindy Wood covers news from City Hall and notable court cases for The Transcript. Contact her at [email protected] or 405-416-4420.

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