American Association of State Highway and Transportation Officials
Special Committee on Research and Innovation
FY2023 NCHRP PROBLEM STATEMENT TEMPLATE
Problem
Number: 2023-G-08
Problem
Title
Pedestrian Crosswalk Spacing and Placement Guidance to
Improve Safety
Background
Information And Need For Research
An estimated 6,205 pedestrians were killed in traffic
collisions in the U.S. in 2019 – a 44% increase in pedestrian fatalities since
2010, representing 17% of total traffic fatalities. Over 80% of those
pedestrian fatalities occurred at unmarked midblock locations. Roadway safety
is a shared responsibility and while some fatalities are due to pedestrian
negligence, many cases result from a system that prioritizes automobile
mobility at the expense of pedestrian safety. Research has found that locations
where pedestrians are most likely to cross outside crosswalks are highly
influenced by the surrounding roadway environment and characteristics, such as
pedestrian volume, number of bus stops, vehicular volume, distance between
crosswalks, and crossing distance. For most pedestrians to walk far out of
their way to cross a street at a marked crosswalk would contradict basic human
behavior. Therefore, to prevent needless fatalities and injuries, we must
provide safely designed crosswalks that are properly spaced so that pedestrians
can practically utilize them. While prior research has established the safety
and effectiveness of countermeasures such as refuge islands, pedestrian hybrid
beacons (PHBs), and rectangular rapid flashing beacons (RRFBs) and provides
guidance (e.g. STEP guide) for selecting countermeasures at uncontrolled
crossing locations, current guidance and research regarding midblock crosswalk
spacing is limited. The ongoing study NCHRP 03-141 - Guidance on Midblock
Pedestrian Signals (MPS) will assess the safety effects of MPS and develop
language suitable for inclusion in the MUTCD, but more work is needed to
understand suitable spacing of these treatments. The AASHTO Council on Active
Transportation’s Research Roadmap (July 2021) identifies “Determining
context-driven optimal spacing between marked crosswalks” as one of their six
highest-priority needs. This research aims to reduce pedestrian fatalities and
severe injuries through a better understanding of appropriate midblock
crosswalk spacing.
Literature
Search Summary
National crosswalk spacing guidance is ambiguous, with
Section 3B.18 of the MUTCD stating: “Crosswalk lines should not be used
indiscriminately. An engineering study should be performed before a marked
crosswalk is installed at a location away from a traffic control signal or an
approach controlled by a STOP or YIELD sign.” Although it is recommended that
the engineering study consider the distance from adjacent signalized
intersections and the possible consolidation of multiple crossing points, there
are no specific criteria offered in terms of spacing and no specific criteria
that take varying infrastructure and land use conditions into account.
Several state guidelines for crosswalks refer to the
American Association of State Highway and Transportation Officials (AASHTO)
Stopping Sight Distance formula. This formula combines a driver’s reaction
time, braking distance, travel speed, and roadway grade to calculate the
distance necessary for a vehicle to make a complete stop. AASHTO recommends
that midblock marked crosswalks not be installed where sight distance and sight
lines are limited. However, while this guidance identifies where marked
crosswalks should not be installed, it does not directly inform where they
should be installed and their appropriate spacing.
To ensure efficient traffic operations, many agencies have
also adopted requirements that preclude marking a crosswalk within a close
distance of another crossing. These requirements generally specify a minimum
distance of 200-600 feet between a midblock crosswalk and the next nearest
marked crosswalk (see e.g., Arizona Department of Transportation; City of
Boulder; City of Sacramento; Florida Department of Transportation; Georgia
Department of Transportation; San Francisco Municipal Transportation Agency;
Utah Department of Transportation; Vermont Agency of Transportation; Virginia
Department of Transportation).
While these minimum distances are important to ensure
safety and efficient traffic operations, the maximum suitable distance between
crosswalks is more critical for ensuring that there are adequate crossing
opportunities that are designed appropriately to reduce the risk of pedestrian
crashes. After a thorough review of crosswalk guidance, the Portland (OR)
Bureau of Transportation appears to be the only agency with a recommended
maximum distance between pedestrian crossings (530 feet within pedestrian
districts and 800 feet outside pedestrian districts). Note, however, that these
guidelines have not been rigorously studied.
The only relevant research that we could find (from the
1995 Nationwide Personal Transportation Survey) reported that about 25 percent
of pedestrians stated they would walk 550 feet to a controlled crosswalk and 50
percent would walk 200 feet. Such findings may help define the relationship
between crosswalk spacing and pedestrian compliance.
In this vein, research could examine not just the maximum
distance that pedestrians will walk to a marked crosswalk, but also their
preferred distance. It would also be warranted to explore these criteria in
different geographic locations including urban versus suburban, varying land
uses, and different regions of the country. This would be useful for regions
with relatively fewer pedestrian collisions that do not have a clear pattern. A
vitally important aspect will also be to account for roadway classification and
characteristics including vehicle speed and volumes as recommendations will
need to balance safety and operations.
More research is needed to provide states and cities with
guidance on the important criteria of maximum crosswalk spacing. Providing
appropriately spaced crosswalks that are properly designed for the specific
roadway conditions may improve the safety and security of pedestrians.
Research
Objective
The research aims to determine the maximum distance
pedestrians will travel to use a crosswalk and develop crosswalk spacing
recommendations in various contexts, based on pedestrian behavior and
willingness-to-deviate. A better understanding of this spacing will help to
inform when to add marked crosswalks at uncontrolled midblock locations to
discourage pedestrians from crossing at higher-risk locations between
crosswalks. In addition to crosswalk spacing, the research will explore factors
that influence pedestrians’ choice to divert from an unmarked direct crossing
path toward a marked crossing in terms of origin/destination proximity, land
use context, and crossing need. Considerations may include: pedestrians’
vehicle gap acceptance, the number of conflict points at crossings, the impact
of vehicle volumes, vehicle speeds, number of travel or turn lanes, pedestrian
travel distance, crossing distance, and different levels of midblock crosswalks
(e.g. signage, flashing beacons, curb extensions, road diet, HAWK signals,
etc.).
Research tasks may include:
1. Literature review of existing strategies and research
regarding crosswalk spacing compliance and safety outcomes with a focus on
human factors.
2. Data collection (crosswalk location and land use and
transportation context, pedestrian compliance and safety outcomes, roadway
environment such as lighting, geometry, facilities, vehicle speeds and volumes,
operational details, users, vehicles, etc.).
3. Survey pedestrians to explore willingness to deviate
to cross at a marked crosswalk across a variety of land-use contexts.
4. Identify compliance and safety outcomes related to
crosswalk spacing and context.
5. Propose solutions and guidance for agencies on maximum
crosswalk spacing.
Urgency
And Potential Benefits
This research will inform design guidance and work to
counteract the trend of increasing pedestrian fatalities and severe injuries at
midblock crossing locations. The trend is found throughout the country and will
be of interest to a majority of state DOTs as well as regional and local
agencies. Findings will also serve to greatly improve overall pedestrian
safety, with benefits being directly borne by some of the most vulnerable users
of our roads.
This research was ranked #4 by the AASHTO Committee on
Safety.
Implementation
Considerations
Traffic and geometric design professionals responsible
for facility design and planning will be most likely to use the research
results.
AASHTO committees that might be interested in the
research results and could help with implementation include the AASHTO
Technical Committee on Nonmotorized Transportation (Rodger Gutierrez, P.E.;
503-986-3554; rodger.c.gutierrez@odot.state.or.us) and the AASHTO Safety
Committee (Kelly Hardy, P.E.; 202-624-5868; khardy@aashto.org).
Recommended
Research Funding and Research Period
Funding to accomplish research objectives and
communication activities is estimated at the level of $400,000-$500,000. A
research period of 24-36 months is expected.
Problem
Statement Author(S): For each author, provide their name, affiliation, email
address and phone.
Nicholas N. Ferenchak, Ph.D., P.E.; Civil, Construction
& Environmental Engineering Department, University of New Mexico;
505-277-0698; Ferenchak@unm.edu
Potential
Panel Members: For each panel member, provide their name, affiliation,
email address and phone.
Sirisha Kothuri, Ph.D.; Civil and Environmental
Engineering Department, Portland State University; 503-725-4208;
skothuri@pdx.edu
Robert J. Schneider, Ph.D.; Department of Urban Planning,
University of Wisconsin-Milwaukee; 414-977-7740; rjschnei@uwm.edu
Marie-Soleil
Cloutier, PhD., Institut National de la Recherche Scientifique, Centre
Urbanisation Culture Société, 514-499-4096, marie-soleil.cloutier@inrs.ca
Person
Submitting The Problem Statement: Name, affiliation, email
address and phone.
Adnan Qazi, P.E.
Arkansas Department of Transportation
AASHTO Committee on Safety, Research Subcommittee Chair
501-569-2642
Adnan.Qazi@ardot.gov