Work on bike and pedestrian counting by University of Minnesota researchers and MnDOT has been highlighted as part of the FHWA’s Livable Communities Case Study Series.
The case study features the Minnesota Bicycle and Pedestrian Counting Initiative, led by the U of M’s Greg Lindsey and MnDOT’s Lisa Austin and Jasna Hadzic. Under the initiative, the team has developed general guidance and consistent methods for counting bikes and pedestrians. Team members have also worked with other state and local agencies to implement counting strategies across Minnesota.
The case study showcases the initiative as an example of how agencies can leverage partnerships to implement a successful counting program for nonmotorized traffic. These traffic counts can help agencies identify safety concerns, understand and communicate benefits of active transportation, prioritize investments, and analyze trends. According to the FHWA, the results can help inform decisions that make biking and walking viable transportation options in livable communities.
There’s nothing like colored concrete to make a crosswalk, sidewalk or breezeway look snazzy.
But the extra touch that many cities are putting into their downtown streetscapes may not be so pretty in just a few short years.
Early cracking has prompted the city of Vadnais Heights to tear up its colored concrete, and the city of Centerville — which installed colored concrete only six years ago — plans to follow suit, said MnDOT’s Senior Road Research Engineer Tom Burnham.
Both cities participated in a recent study, sponsored by the Local Road Research Board and conducted by MnDOT, to determine what is causing the early deterioration.
Across Minnesota, many of the estimated 45 colored concrete projects have experienced early deterioration, particularly microcracking near contraction joints. While this type of distress also occurs with regular concrete, it appears to be accelerated in the colored concrete projects, within five years in some instances.
Although the newly released study identifies likely causes for the failing colored concrete, further research is needed to evaluate proposed solutions.
Researchers determined that the colored concrete mixtures have likely been too porous for Minnesota winters, allowing deicing chemicals to leach in and wreak havoc. Although not quite as problematic for sidewalks and medians — which aren’t salted as heavily — it is especially bad for colored crosswalks.
A denser concrete mixture (one formed with less water) is recommended; however, constructing the concrete panels this way will require extra steps.
“There are chemicals that can be added to the mixture to artificially lower that water-to-concrete ratio,” Burnham said. “This will allow a denser mixture to be more easily placed.”
Color in vogue
Although there was a spate of colored concrete construction in Ramsey County in the late 1990s, it has only come into fashion in the rest of the state within the last five to six years, according to Burnham.
“You go to almost any community and they’re installing it — on their sidewalk and medians and also crosswalks,” said Burnham, who coordinated the research study.
Because of the added expense, cities may be very disappointed in the results.
The city of Stillwater, which installed a colored concrete panel crosswalk on its main street just two years ago (see top photo), is already experiencing cracking and deterioration in several panels.
Although reducing the porosity of the colored concrete mixture should help, it won’t solve everything.
Another issue is the curing. The typical white curing product can’t be applied like it is with standard concrete, so curing the colored panels is more challenging, Burnham explained.
There are possible remedies, however, to assist with the curing, such as wet burlap or curing blankets.
Adding complexity to the issue are the new deicing chemicals on the market, which are also impacting regular road materials.
Several test samples showed evidence of chemical attack of the cement paste and fine aggregates, as well as an alkali-silica reaction, which can cause cracking or spalling and isn’t normally seen in regular concrete.
“Is there anything unique with the coloring that would accelerate the observed chemical reactions? We didn’t feel we had enough samples and knowledge at this point to conclusively say,” Burnham said.
Different construction techniques could go a long way toward increasing the livelihood of colored concrete; however, it could take several years of observation to determine if other methods work.
MnROAD is considering adding colored concrete panels to its facility for testing.
Until more questions are answered, MnDOT researchers are recommending repair techniques and alternative streetscaping ideas to cities, such concrete stains, pavers or colored high friction surface treatments.
In addition to sharing the findings with cities and counties, Burnham wants to educate contractors.
“We hope this research is a wake-up call for the colored concrete industry too because we don’t want the industry to die in Minnesota,” he said. “If it can work, we want cities and counties to be able to use it.”
*Editor’s Note: This story was updated 09/04/2014 to specify that this research project was funded entirely by the Local Road Research Board, and that MnDOT conducted the research.
Investigation and Assessment of Colored Concrete Pavement — Final Report (PDF, 20 MB, 368 pages); Technical Summary (forthcoming)
Last year, 41 people were killed while walking or biking on Minnesota roads and nearly 1,700 were injured.
Dozens of measures are available, however, for making roads safer for pedestrians and cyclists. Minnesota Department of Transportation Pedestrian and Bicycle Safety Engineer Melissa Barnes reviewed some of these design techniques in a recent presentation to city and state transportation engineers. (Watch the full webinar.)
We asked Barnes to highlight her favorite bike and pedestrian safety countermeasures used in Minnesota.
Rectangular Rapid Flashing Beacon
An unusually effective new pedestrian warning device, called the Rectangular Rapid Flashing Beacon, has become quite popular.
User-activated, the device alerts drivers to a pedestrian’s presence with a bright flashing beacon that “looks kind of like an ambulance or fire truck light,” Barnes said. (RRFBs can also be activated passively by a pedestrian’s presence.)
Studies have shown that the number of motorists stopping for pedestrians increases from 18 to 81 percent with the RRFB. Another plus: the device doesn’t appear to lose its effectiveness over time. After two years, compliance has been shown to still be more than 80 percent.
Advanced Stop Lines
It’s not uncommon for a motorist to stop for someone in a crosswalk, only for the vehicle following them to not see the pedestrian and veer around, driving through the crosswalk.
But an advanced stop line, placed 20 to 50 feet prior to a crosswalk, is effective at making both vehicles stop and see the person in the crosswalk.
“They are a really good option at an unsignalized, mid-block crossing,” said Barnes, although the stop line may not be a good option for a two-way stop.
Advanced stop lines have been shown to reduce pedestrian-vehicle conflict up to 90 percent; however, stop lines shouldn’t be placed too far in advance of the crossing, because motorists might then ignore them.
Leading Protected Interval
An innovative treatment called the Leading Protected Interval minimizes conflict by allowing pedestrians to enter a signalized intersection before vehicles do.
The walk signal begins three to seven seconds before the parallel street turns green by extending the time all lights are red.
A right turn on red can be prohibited with this device; however, even without the prohibition, the Leading Protected Interval has been shown to reduce crashes by 5 percent.
Protected Bike Lanes
Bike lanes buffered from traffic with some sort of physical barrier, even parked cars, will reduce all types of crashes. They also increase comfort levels for cyclists, helping keep bikes off the sidewalk.
“A lot of people are much more comfortable biking in these than a regular bike lane,” Barnes said. “It can be a very effective solution for places with lots of cyclists.”
Protected bike lanes, also called cycle tracks, also have a traffic-calming effect.
In New York City, the cycle track reduced all types of crashes an average of 40 percent and up to 80 percent on some roads.
“The challenge is how to design these at intersections,” Barns said. “It’s hard to get the turns right and get everybody visible. It’s pretty important to design these carefully at intersections.”
For those reasons, two-way cycle tracks work best on one-way streets, she said.
Flexible bollards create temporary curb lines that encourage vehicles to slow down. They can be installed easily and inexpensively.
Flexible bollards bend up to 90 degrees when struck by an errant vehicle. They do not physically stop a car, but encourage vehicles to stay within their lane. Although they can create additional maintenance, they are a good interim solution at locations that need an immediate fix, but have no funding to do so.
City and county engineers often struggle with how to respond to safety concerns about pedestrian crossings, with no scientific method for evaluating them.
In Long Lake, for example, the police department received numerous complaints about the safety of a particular pedestrian crossing. But when the crossing was videotaped, no one was observed using it.
This example — which was part of a research project funded by the Local Road Research Board — exemplifies the difficulties local governments face when they receive requests for a stop sign or signals at a crossing.
The soon-to-be released guidebook* recommends when to install marked crosswalks and other enhancements based on the average daily vehicle count, number of pedestrians, number of lanes and average vehicle speed. It guides users how to rate a crossing for pedestrian service, and includes a flow chart to assist in decision-making.
The training is unique because it is based on actual video footage of existing crosswalks and the pedestrians which use them.
Although vehicles are legally required to stop for pedestrians crossing at intersections and within marked crosswalks, they don’t always yield the right-of-way. And areas with high traffic volumes may not have adequate gaps for pedestrians to cross safely, leading to risk-taking.
Alan Rindels, a MnDOT research engineer, had previously looked for a methodology to evaluate a crosswalk’s effectiveness, but could not find an appropriate engineering analysis.
“What I kept coming up with were results based on the experience of an engineer or planner for what they ‘felt’ was a better crosswalk, such as additional pavement markings, lights or maybe a signal system,” he said.
Rindels finally found guidance in a Transportation Research Board webinar two years ago. Based on that, he asked the LRRB to develop a training methodology for Minnesota practitioners.
Uncontrolled pedestrian crossings
Unless specifically marked otherwise, every intersection is a pedestrian crossing, regardless of the existence of crosswalk markings or sidewalks. At mid-block locations, crosswalk markings legally establish the pedestrian crossing. Uncontrolled pedestrian crossings (which the guidebook focuses on) are locations that are not controlled by a stop sign, yield sign or traffic signal.
Defining where to place pedestrian crossing enhancements — including markings, signs and or other devices — depends on many factors, including pedestrian volume, vehicular traffic volume, sight lines and speed.
The LRRB developed a worksheet that engineers can use to evaluate an uncontrolled pedestrian crossing location in a systematic way, in accordance with the 2010 Highway Capacity Manual. Users note the level of lighting, distance from the nearest all-way stop and whether another location might serve the same pedestrian crossing more effectively.
The guidebook’s 11-step evaluation can identify what level of treatment is appropriate, ranging from overhead flashing beacons and traffic calming devices, such as curb bump-outs, to more expensive options like building overpass or underpass.
Hennepin County Senior Transportation Engineer Pete Lemke, who went through pre-training, said the guidebook will help engineers measure the pedestrian experience by “quantifying the delay at non-signalized intersections.”
“It will inform how we respond to concerns — whether that response is ‘the crossing fits the needs of what’s there’ or ‘we need to make changes or enhancements,'” he said.
Putting Research Into Practice: A Guide for Pedestrian Crossing Treatments at Uncontrolled Intersections – Technical Summary (1 MB, 2 pages); Final Report.
* Consultant Bolton & Menks prepared the guidebook with guidance from a 21-member project team that included University of Minnesota researchers and engineers from the city of Eagan, Hennepin County, Carver County, Scott County, MnDOT, the Center for Transportation Studies and the Federal Highway Administration.
(Feature image courtesy Michael McCarthy, Center for Transportation Studies.)
Earlier this year, we wrote about the Minnesota Bicycle and Pedestrian Counting Initiative, a project that developed guidelines and protocols to help transportation planners accurately count non-motorized traffic. This groundbreaking research involved a diverse partnership of state and local officials, University of Minnesota faculty, and private and nonprofit organizations.
On Wednesday, April 23, the project team (photo above) was honored with an award from the Center for Transportation Studies. Team members accepted the CTS Research Partnership Award in a ceremony at the McNamara Alumni Center in Minneapolis. The award is given each year to projects that have resulted in “significant impacts on transportation” and that draw on “the strengths of their diverse partnerships” to achieve their results.
The video below, produced by CTS, explains the importance of the project. MnDOT is now in the process of implementing the research results by installing permanent counters and using portable counters in select locations around the state. MnDOT plans to use the information for a variety of purposes, including planning, safety analysis, investment planning and quality-of-life analysis.
Each year, approximately 17 percent of road construction work zone fatalities nationwide are pedestrians.
At special risk are the visually impaired, who rely on walking and public transportation to get around.
A major challenge for them is crossing the street — which is even more difficult if an intersection is torn up.
MnDOT has invested significant effort to accommodate pedestrians, particularly those with disabilities, in temporary traffic control situations. This includes requiring temporary curb ramps and alternative routes when a sidewalk is closed.
Researchers, funded by MnDOT, have now developed a cell phone application to guide blind pedestrians around a work-zone.
Building on previous work to provide geometric and signal timing information to visually impaired pedestrians at signalized intersections, the smartphone-based navigation system alerts users to upcoming work zones and describes how to navigate such intersections safely.
The smartphone application uses GPS and Bluetooth technologies to determine a user’s location. Once a work zone is detected, the smartphone vibrates and announces a corresponding audible message. The user can tap the smartphone to repeat the message, if needed.
The federal government strongly encourages states to provide either audible warnings or tactile maps at work zones where visually impaired pedestrians are expected to be impacted.
“The smartphone application is a step in that direction,” said MnDOT technical liaison Ken Johnson. “It’s a way to see if this type of way-finding device would work.”
Since smartphone use is still limited, the state is also interested in special equipment that could relay the audible warnings at affected work zones.
“However, smartphone use is increasing in the general population, as well as with persons with disabilities, and there will likely be a day when it will be rare to not have a smartphone and this tool could meet road agency needs,” Johnson said.
Before developing the smartphone application, researchers surveyed 10 visually impaired people about their experiences at work zones and what types of information would be helpful in bypass or routing instructions.
The University of Minnesota research team, led by Chen-Fu Liao, tested the smartphone application by attaching four Bluetooth beacons to light posts near a construction site in St. Paul.
Additional research is now needed to conduct experiments with visually impaired users and evaluate system reliability and usefulness.
To prepare for a multimodal future, state agencies must be able to plan and engineer a transportation system for all modes of transportation, including bicycle and pedestrian traffic.
The Minnesota Bicycle and Pedestrian Counting Initiative was launched to develop consistent methods for monitoring non-motorized traffic across the state. Researchers developed guidelines for manual counts using state and national examples, and they also created methods for extrapolating annual traffic volumes from short-duration automated counts, for integration into MnDOT’s vehicular count database program.
The guidance developed for manual counts includes forms, training materials, public information for passers-by, links to smartphone applications that provide counting locations and spreadsheets for reporting results.
MnDOT hosted six workshops and a webinar to introduce local officials to the initiative and recruit participants for pilot field counts. Researchers then analyzed how these field counts could be used with existing automated counts to extrapolate daily or annual data.
MnDOT has installed some of the very first automated counting equipment on a state road — Central Avenue NE in Minneapolis (on the bike lane) and Highway 13 in Eagan (on a shoulder). As of 2012, six agencies in Minnesota counted non-motorized traffic (annual reports are available from the city of Minneapolis and Transit for Livable Communities), and even though comprehensive data is not yet available, Minnesota is a leader in this type of monitoring with more than 1,000 manual count locations and 32 automatic count sites.
Because of Minnesota’s experience, researchers collaborated with the National Cooperative Highway Research Program’s national Methodologies and Technologies for Collecting Pedestrian and Bicycle Volume Data research project, due for release in 2014, and contributed to the Federal Highway Administration’s effort to update its Traffic Monitoring Guide to include a chapter on non-motorized traffic.
Judging by the response we get whenever we post anything bicycle- or pedestrian-related on MnDOT’s social media channels, people seem to be hungry for research into this area. We recently had several new reports arrive on the topic, and I thought I’d share them here for those who missed them, along with links to any related webinars or news articles.
The Minnesota Bicycle and Pedestrian Counting Initiative: Methodologies for Non-motorized Traffic Monitoring
This study examined ways of counting non-motorized traffic (bicycles and pedestrians), with the goal of helping planners and engineers better incorporate these modes into our transportation systems. The report discusses the pros and cons of various counting methodologies (i.e. manual field observation, active and passive infrared systems, magnetic loop detectors, etc.) and looks at how Minnesota agencies are using them. The project also included a webinar, workshops and a coordinated statewide pilot count in dozens of communities around the state.
Best Practices Synthesis and Guidance in At-Grade Trail-Crossing Treatments
At-grade trail crossings have frequently been the sites of bicycle, pedestrian and snowmobile crashes in Minnesota and throughout the nation. The goal of this document is to synthesize best practices observed statewide and nationally in order to provide engineers and other transportation professionals with guidance on safety treatment applications at trail crossings.
Minnesota’s Best Practices for Pedestrian/Bicycle Safety
This Local Road Research Board-funded guide is designed to be used as a resource to assist local agencies in their efforts to more safely accommodate pedestrians and bicyclists on their systems of roads and highways. It discusses the relative merits of a wide range of strategies to reduce crashes involving bicycles and pedestrians.
Complete Streets Implementation Resource Guide for Minnesota Local Agencies
In this project, investigators developed a guide to help local agencies implement Complete Streets programs, including sample policy language from agencies in Minnesota, systems for classifying roadways that are appropriate for use in context-sensitive planning and a worksheet to help develop specific project plans.
Bike, Bus, and Beyond: Extending Cyclopath to Enable Multi-Modal Routing
Researchers incorporated multimodal routing into the Cyclopath bicycle route-finding tool to allow users to find routes that combine biking and transit for journeys where biking alone is impractical. Increasing the percentage of trips made by methods other than cars is a MnDOT priority, and providing route information can help to make alternative transportation options more viable.
This fall, CTS will offer five research seminars on transportation topics ranging from resilient communities to asphalt at low temperatures.
Seminars will be held every Thursday from September 26 through October 31 (except Oct. 17) on the U of M campus in Minneapolis. You can either attend in person or watch the live webcast of each seminar. Additional information is available on the CTS website.