Widening the Interstate 30 corridor through downtown Little Rock and North Little Rock to 10 lanes or more will increase congestion rather than reduce it, according to a consultant retained by opponents of the $630 million project.
Norman Marshall, president of Smart Mobility Inc., a transportation consulting firm based in Vermont, said the counterintuitive conclusion was reached after his firm applied more advanced traffic modeling to the 6.7-mile corridor that includes the I-30 bridge over the Arkansas River.
He said the state highway engineer traffic projections were based on modeling that was outdated, flawed and didn't fully account for the amount of traffic that a wider corridor would attract from other roadways, such as Interstate 440. Also, motorists who now avoid the congested I-30 and use the Broadway and Main Street bridges to cross from Little Rock to North Little Rock and vice versa would revert to using the wider I-30 corridor, the report said.
Further, the report said, some travelers who now avoid peak travel periods would return to the peak travel periods. And a faster freeway route would encourage more sprawl, another example of what the report called induced demand.
On any urban freeway project, induced travel would counteract any potential congestion relief, according to a University of California study cited in the report.
The university study's conclusion is that no matter how many lanes are added to the I-30 corridor, "the level of congestion would remain the same," according to the report.
The report cited 10 examples around the nation of freeway widenings that didn't ease congestion as forecast. The most notable example was the Katy Freeway in Houston, which at 26 lanes is the widest in the world, yet is the eighth-most congested freeway in Texas.
"Urban freeway congestion cannot be solved through expansion because induced travel always follows roadway expansion," the report said. "The larger roads just fill up with traffic again."
Marshall made a presentation on the report Tuesday at the Little Rock Board of Directors agenda meeting. It came two weeks before the Highway and Transportation Department's April 26 public meeting, where the agency is scheduled to present its modifications to its initial I-30 corridor recommendations.
Department officials have not seen the report and, thus, weren't in a position to comment, said Danny Straessle, an agency spokesman.
Marshall said Smart Mobility is being paid by the Arkansas Public Policy Panel, an advocacy group that was founded in the early 1960s to foster school integration and is long associated with other community causes. The cost of the study was not disclosed.
The company was established in 2001 as a consulting firm based in Norwich, Vt., with a focus on integrating transportation and land-use modeling, engineering and planning. Marshall, according to the firm's website, "specializes in developing advanced tools and techniques for travel-demand modeling, regional air quality modeling, and analysis of land use/transportation systems, with a goal of developing more meaningful indicators from regional transportation models."
Among its projects is the development of a two-lane alternative to a proposed four-lane widening project on a highway through a rural agricultural area in Chester County, Pa. Initially working with a group of concerned citizens, the two-lane proposal is part on an environmental impact study now underway by the Pennsylvania Department of Transportation.
Smart Mobility is working with a small group called "Improve 30 Crossing," led by Tom Fennell, a Little Rock architect who has been refining his proposal to develop the I-30 corridor in downtown Little Rock as a boulevard or a route that could be converted into one.
Fennell and others who support him say the Highway Department's project is too big and would hurt the ongoing revitalization of downtown Little Rock.
Others have applauded the 10-lane I-30 alternative and other changes arrived at during a yearlong evaluation process. A department re-evaluation of the 10-lane and eight-lane alternatives will be part of the April 26 meeting.
Both sides represent differing visions of the scope of the project to ease congestion and increase safety on I-30 between Interstate 530 in Little Rock and Interstate 40 in North Little Rock. In addition to replacing the river bridge, the project would make improvements to a short section of I-40 between I-30 and U.S. 67/167.
Much of the corridor is more than 50 years old, with outdated interchanges and little in the way of shoulders, and has a crash frequency rate that's more than 30 percent higher than similar corridors, according to the department. The river bridge carries about 125,000 vehicles daily.
Little Rock also has retained a consulting firm to study the project and make recommendations. Representatives of the firm are expected to provide an update on their progress to the city board on April 26 and attend the department meeting that day, Little Rock Mayor Mark Stodola said after Marshall's presentation.
Marshall told city directors that some congestion should be encouraged. "You need congestion to spread out the traffic," he said. "Spreading out the traffic is desirable."
The report dismissed the department's modeling that showed a 1 percent annual growth rate in traffic between 2014 and 2041, which would mean that even if nothing were done to the corridor, it would see a 31 percent increase in traffic. That is the equivalent of an additional lane of traffic in both directions, according to the report.
"That clearly could not happen if the bridge stays at 6 lanes," the report said.
The report presented Tuesday was the first phase of Smart Mobility's study and recommendations, examining the methodology the Highway and Transportation Department used.
Marshall said he plans to present the second phase next month. It will evaluate potential options to expand the local street system, including building a bridge over the Arkansas River at Chester Street, which Marshall said would divert more traffic than the estimated 3 percent the department has forecast.
The second report will also evaluate converting I-30 in downtown Little Rock into either a boulevard or a combination boulevard and expressway without ramps, he said.
City Director B.J. Wyrick asked Marshall how he came up with those alternatives.
"Well, this is partly through discussions with my clients," he said. "Just like any consultant, you listen to your client's ideas. I have a couple of ideas of my own."
Metro on 04/13/2016