Category Archives: Research

General research posts.

Do streetcars support commercial development? New Orleans results say yes

New streetcar lines are in the planning stages in Minneapolis and St. Paul. Proponents cite not only the lines’ ability to strengthen the transit system, but also their potential as catalysts for development. Estimating the impacts of streetcars is challenging, however, as most U.S. lines operate in downtown areas with many interrelated factors at play. A recent U of M research project examined the issue through the prism of one city’s experience: post-Katrina New Orleans.

The team—research fellow Andrew Guthrie and Assistant Professor Yingling Fan of the Humphrey School of Public Affairs—analyzed building permits near streetcar stops in the downtown business district and in several urban neighborhoods.

“Hurricane Katrina allowed—or required—more redevelopment to occur at a faster pace than 
normal, potentially allowing existing streetcar lines’ latent development impacts to appear,” Guthrie says. “This created an unfortunate yet rare opportunity for study.”

streetcars

The researchers estimated how the frequency of commercial and residential permits changed with distance from streetcar stops, controlling for hurricane damage, proximity to existing commercial areas, and pre-Katrina demographics.

They found that throughout the system, building permits strongly reflect the distance to stops—and that commercial and residential permits move
 in opposite directions within the first 750 feet.

Commercial permits declined the further away the location was from a stop. In residential areas, commercial permits show variation depending on neighborhood characteristics. The number of neighborhood residential permits rose about 24 percent with every 100 feet from a stop.

Based on their results, Guthrie and Fan conclude that traditional streetcar lines can help increase commercial development not just in downtown business districts, but in other urban areas as well. The findings also indicate that streetcars
 shape development in urban neighborhoods in
 a fundamentally different fashion than light rail.

Read the full article in the January issue of Catalyst.

Exploring Nice Ride job accessibility and station choice

Although bike share systems are becoming more popular across the United States, little is known about how people make decisions when integrating these systems into their daily travel.

In a study funded by CTS, researchers from the U of M’s civil engineering department investigated how people use the Nice Ride bike share system in Minneapolis and St. Paul. The researchers examined how Nice Ride affects accessibility to jobs and developed a model to predict station choice.

In the first part of the study, the researchers created maps showing accessibility to jobs by census block for both Nice Ride and walking—as well as the difference between the two—at time thresholds ranging from 5 to 55 minutes.

Overall, in blocks with both Nice Ride and walking job accessibility, Nice Ride provides access to 0.5 to 3.21 times as many jobs as walking.

By comparing Nice Ride to walking, the study demonstrated that walking can successfully be used as a baseline to show how a bike share system improves job accessibility. The results also pinpointed when and where Nice Ride had the strongest accessibility advantage over walking.

“This type of information can be used by bike share system planners to identify where new stations could be built to maximize their impact on job accessibility,” says grad student Jessica Schoner, a member of the research team.

In addition, the team developed a theoretical model for bike share station choice. The model considers users’ choice of a station based on their preference 
for the amount of time spent walking, deviation from the shortest path (the closest station may not be in the direct path of the person’s destination), and station amenities and neighborhood characteristics.

Findings show that people generally prefer to use stations that don’t require long detours to reach, but a station’s surroundings also play an important role. Results also indicate that commuters value shorter trips and tend to choose stations that minimize overall travel time.

According to Schoner, understanding people’s station preference can help provide guidance to planners that want to expand or optimize a bike share system.

Read the full article in the January issue of Catalyst.

Culvert research aims to protect endangered small fish

The Topeka shiner
The Topeka shiner, a small minnow that inhabits slow-moving prairie streams, was once widespread and abundant in portions of Iowa, Kansas, Minnesota, Missouri, Nebraska and South Dakota. It now inhabits less than 10 percent of its original geographic range.
(Photo courtesy of the Minnesota Department of Natural Resources)

In a new study funded by the Minnesota Department of Transportation, engineers are trying to ensure that new culverts do not degrade the habitat of an endangered fish in southern Minnesota.

The state has already researched how to better accommodate fish passage at river and stream crossings. Now it is looking at design guidelines for culverts that specifically impact the Topeka shiner, a small endangered fish found in five Midwestern states.

In Minnesota, the Topeka shiner is known to live in at least 57 streams, totaling 605 miles, within the Big Sioux and Rock River watersheds.

“The Topeka shiner is reported to have been erased from about 50 percent of its historic range in Iowa and much of its range in Minnesota, which is why Minnesota is so intent on doing what it can to help this fish thrive here,” said Alan Rindels, MnDOT’s project coordinator for the research.

The Topeka shiner is endangered due to the degradation of stream habitat, stream channelization, non-native predatory fishes and construction within waterways.

Culverts might impede the passage of this small minnow for a number of reasons, including that they might be too long, lack sufficient depth or carry water too fast.

Culverts allow water to pass under roads.
Culverts (also called small bridges) allow water to pass under roads. Occasionally, they can harm a stream’s fish habitat by inadvertently acting as a barrier to fish passage or migration. On the West Coast, large-scale efforts are under way to protect migratory salmon, and in Minnesota, culvert designers are concerned about fresh water species.

In addition, long culverts block sunlight, which possibly discourages fish from swimming through. Typically, older culverts are replaced with longer culverts to improve road safety and minimize maintenance costs. To eliminate or minimize impacts to the Topeka shiner, the state is trying to determine if light mitigation strategies are necessary.

Researchers from the University of Minnesota’s St. Anthony Falls Research Laboratory will monitor a newly installed culvert (110 feet in length) and a few other culverts in critical Topeka shiner habitat streams during spawning and fall movement.

Additionally, a laboratory-based light manipulation experiment will examine the behavior of the warm-water fish when presented with a dark culvert.

Guidelines for culvert design in Topeka shiner habitat will be developed based on these results, as well as examples from neighboring states. The state is also collaborating with the U.S. Fish and Wildlife Service and affected Minnesota counties.

Uncovering manufacturers’ perspectives on the transportation system

It’s no secret that manufacturing plays a key role in driving economic growth, or that transportation is essential for the success of any manufacturing operation.

While the relationships among manufacturing, transportation, and economic growth have been studied on a large scale, there is often little dialogue between transportation organizations and the manufacturers themselves. A recently completed pilot study conducted jointly by the Minnesota Department of Transportation (MnDOT), the University of Minnesota Humphrey School of Public Affairs, and University of Minnesota Extension aims to address this communication gap.

The pilot project focused on 12 counties in southwest Minnesota, where more than 172 regional businesses were contacted for participation and 75 in-person interviews were completed with manufacturers, shippers, and carriers. During the interviews, participants were encouraged to focus their comments on high-value, low-cost improvements that MnDOT can address in the short term without over-promising projects that currently cannot be funded.

Participants identified the need for smooth pavements and wide shoulders, the value of advance warning lights at intersections with traffic signals, the importance of highway safety, and the challenges of maneuvering oversized vehicles through roundabouts, among others.

The research team is compiling the pilot study’s findings into a final report. In the meantime, MnDOT is working to address a number of the challenges and suggestions uncovered through the pilot program.

Read the full article in the December issue of Catalyst.

MnDOT, LRRB announce new research projects

Minnesota’s next round of transportation research projects will explore using traffic signal data to predict crashes, evaluate various impacts of bicycling on the state and address a range of other transportation issues.

The state’s two transportation research governing boards have authorized funding for a total of 24 new research projects. MnDOT’s Transportation Research Innovation Group (TRIG) and the Local Road Research Board announced their Fiscal Year 2015 funding awards this week after hearing proposals from researchers in several states. MnDOT Research Management Engineer Hafiz Munir said the projects, which are listed below, reflect the needs of state and local practitioners.

“Many of the projects fall under the ‘traffic and safety’ or ‘materials and construction’ categories, which I think reflects MnDOT and local agency priorities,” Munir said. “Ultimately, all of these research projects address business needs of the people who build and maintain our roads.”

Links are provided to brief descriptions of each project (as provided by the researchers who submitted the proposals).

Environment

Maintenance

Materials and Construction

Multimodal

Policy and Planning

Traffic and Safety

Previewing MnDOT’s next round of research projects

MnDOT Research Services recently released its 2013 request for proposals. If you have any kind of direct interest in transportation research in Minnesota, chances are you might have known that already. But those with more of a general curiosity might be interested to see the list of research need statements from the RFP, as they provide a nice preview of the next round of potential MnDOT research projects.

As you can see, some are of a highly technical nature. (It’s safe to say that a study on “PCC Pavement Thickness Variation Versus Observed Pavement Distress” would be of interest mainly to engineers.) Others, however, like “The Economic Impact of Bicycling in Minnesota,” might have a broader appeal. In any case, it’s a fascinating glimpse at the myriad of issues that MnDOT is attempting to address through research and innovation.

Here’s the list of research need statements from the 2013 RFP, broken down by category:

Environment

Maintenance

Materials and Construction

Multimodal

Policy and Planning

Traffic and Safety