HomeMy WebLinkAboutPedestrian Crossing Warrant Analysis
October 10, 2020
Mr. Lance Lehigh, PE, CFM
Engineer III, City of Bozeman
PO Box 1230
Bozeman, MT 59771-1230
Reference: West Babcock Street Pedestrian Trail Crossing Study—Bozeman, Montana
Dear Lance:
The purpose of this letter is to provide a summary of a pedestrian crossing study that has been
completed for the West Side Flats Subdivision development, located south of West Babcock Street
and west of Automotive Avenue in Bozeman, Montana. The study was requested by the City of
Bozeman to determine the best application for a pedestrian crossing treatment at the planned
pedestrian trail crossing at West Babcock Street. MDT’s Guidance for Uncontrolled Pedestrian Crossing
Treatment Selection Process and Matrix and the Federal Highway Administration’s (FHWA’s) Guide for
Improving Pedestrian Safety at Uncontrolled Crossing Locations were used as guidance for the evaluation.
Existing Site Conditions
West Babcock Street (L-16-5453) is a west-east route classified as a collector by the City of Bozeman
(per the 2017 Bozeman Transportation Master Plan). At this location, West Babcock Street has
bicycle lanes on the north and south sides of traffic, three lanes of traffic (one through lane in each
direction and a center two-way left-turn lane) and curb and gutter on both sides of the road. The
roadway width is approximately 44 feet. The roadway terminates at South Eldorado Avenue,
approximately 3,700 feet west of Cottonwood Road. The south side of the West Babcock Street has
sidewalk from South Cottonwood Road for approximately 800 feet to the west. The posted speed
on West Babcock Street is 30 mph.
The intent of the West Side Flats project is to develop a 132-unit 2-bedroom apartment subdivision
on the west end of Bozeman that will include five 12-plex and four 18-plex unit complexes. A
pedestrian trail will be constructed on the south side of West Babcock Street, west of the
intersection with South Cottonwood Road. The new trail will connect to an existing pedestrian trail
on the north side of West Babcock Street. To the north of the development is undeveloped land
and the Springhill Presbyterian Church, to the east is undeveloped land and an Enterprise Rental Car
and two car dealerships, to the south is undeveloped land and to the west is a residential
neighborhood.
Existing Traffic Volumes
Sanderson Stewart collected traffic data on West Babcock Street on Saturday, October 10, 2020 and
Tuesday, October 13, 2020. The weekday AM, Noon and PM peak hour periods of traffic were
found to occur between 7:30-8:30 AM, 11:15-12:15 PM, and 4:30-5:30 PM. Raw count data was
adjusted for seasonal variation using Montana Department of Transportation (MDT) seasonal
adjustment factors of 0.923 and 1.165 for Tuesday and Saturday, respectively. Peak hour traffic
volumes for the AM, Noon and PM peak hours of traffic were found to be 27, 100 and 86 vehicles
per hour on Saturday, and 93, 67, and 105 vehicles per hour on Tuesday, respectively. The total
traffic volume on Tuesday, October 13, 2020 was 1155 vehicles per day. Traffic volume summary
sheets are attached to this letter.
Future Growth & Trip Generation
The Bozeman Transportation Master Plan forecasts the traffic volumes to capacity ratio in 2040 to
be 0.31 at the intersection of West Babcock Street and South Cottonwood Road. The plan states
that a project to extend West Babcock Street further west will be developed as the roadway volumes
increase and the demand on that part of the network grows. There are two other Norton Ranch
Subdivision (Phase 5 and Phase 4) proposed developments that have been zoned for residential use
located northwest (Phase 5, approximately 80 acres) and west (Phase 4, approximately 85 acres) of
the West Side Flats but do not have an estimated date for beginning construction.
An accurate estimate of site-generated traffic was made to analyze the impacts of a new
development. This study utilized Trip Generation, 10th Edition, published by the Institute of
Transportation Engineers (ITE), which is the most widely accepted source in the United States
for determining trip generation projections. For the purposes of this study, Land Use Code 225-
Off Campus Student Housing (located further than one half mile from campus) was used to
estimate vehicular trip generation for the West Side Flats Subdivision development. The results
are presented below.
At full buildout, the West Side Flats development is projected to generate a total of 1048 gross
average weekday trips (524 entering/524 exiting) with 42 trips (12 entering/30 exiting) generated
during the AM peak hour and 79 trips (41 entering/38 exiting) generated during the PM peak
hour. This will increase the estimated daily traffic volume on West Babcock Street once the West
Side Flats are fully occupied to increase by 1048 vehicle trips per average weekday, estimating
total ADT on West Babcock Street to be approximately 2203 vehicles per day.
Projected Pedestrian Volumes
Trip generation projections provide an estimate of the total number of vehicular trips that would be
generated by a proposed development. However, the potential for alternate mode (pedestrian, bicycle,
or transit) trips was also considered for this site. With the housing being located in the western part
Intensity Units total enter exit total enter exit total enter exit
264 Bedrooms 1048 524 524 42 12 30 79 41 38
Total Gross Trips 1048 524 524 42 12 30 79 41 38
(1) Off-Campus Student Apartment - Land Use Code 225*Units = Bedrooms
Average Weekday Average Rate =1048 (50% entering, 50% exiting)
Peak Hour of the Adjacent Street, One Hour between 7 and 9 AM: Average Rate = 42 (28% entering, 72% exiting)
Peak Hour of the Adjacent Street, One Hour between 4 and 6 PM: Average Rate = 79 (52% entering, 48% exiting)
*Trip Generation, 10th Edition, Institute of Transportation Engineers, 2017
Off-Campus Student Apartment1
PM Peak Hour
Land Use
Independent Variable Average Weekday AM Peak Hour
of town it is anticipated to be at least occupied by University Students for housing, and therefore
pedestrian and bicycle activity may occur particularly with an existing infrastructure (bike lanes, bike
paths, sidewalks) to support those types of trips.
Reviewing ITE’s trip generation manual (10th Edition), there is no accurate land use providing
pedestrian and bicycle generated values for off-campus apartments or a near campus setting.
Therefore, localized pedestrian and bicycle trip generation for this project came from a study
performed by the MSU ITE student chapter in 2018. For this project MSU ITE collected data
focusing on the Stadium View apartments’ trip generation. Stadium View apartments are located
within similar proximity to campus and houses approximately 500 residents. This population
estimation is approximately 1.9 times the magnitude of the 264 resident accommodations being
developed at the West Side Flats Subdivision. The pedestrian and bicycle traffic data collected is
shown in the table below (directly from Stadium View Trip Generation Report by ITE at MSU).
Using this data, an averaged value of 81 pedestrian and bicycles (combined) trips per hour (based on
averaged peak hour weekday observations) were observed at Stadium View apartments; accordingly,
43 pedestrian and bicycle (combined) trips per hour are expected to be generated from the West
Side Flats Subdivision. This value is comparable to low rise multifamily housing in ITE’s trip
generation estimates.
Uncontrolled Pedestrian Crossing Treatment Selection Process
Referencing the Guidance for Uncontrolled Pedestrian Crossing Treatment Selection Process and Matrix
(Kittelson & Associates, 2019), a matrix can be consulted to help determine what type of crossing
treatment is warranted. The Pedestrian Crossing Treatment Selection Matrix, is shown below for a 3-lane
facility (West Babcock Street).
Following the guidance from the pedestrian crossing treatment selection matrix, with a three-lane
facility with speeds at 30 mph and a vehicle ADT of 2203, the guidance suggests a marked crosswalk
with appropriate signage is an appropriate pedestrian treatment at this location. To confirm this,
FHWA’s Guidance for Uncontrolled Crossings was also evaluated.
FHWA’s Guide for Improving Pedestrian Safety at Uncontrolled Crossing Locations
The Federal Highway Administration (FHWA) has produced the Guide for Improving Pedestrian Safety at
Uncontrolled Crossing Locations to help determine the most appropriate pedestrian crossing treatment
within various roadway environments. The table below is from the report and helps classify
appropriate safety countermeasures for pedestrian crossings dependent on the roadway
characteristics. Using the roadway characteristics of West Babcock Street (2 lane roadway, AADT
less than 9,000 vehicles, and a posted speed limit of 30 mph), it is recommended that high-visibility
crosswalk markings, parking restrictions on crosswalk approaches, adequate nighttime lighting levels
and crossing warning signs are appropriate applications for safety purposes.
Vehicular traffic on West Babcock Street at the time of this study is very low since the street
provides connectivity to one existing residential development on the south side of West Babcock
Street. Using the AADT that was collected at West Babcock Street from current traffic volumes and
trip generation for the new development, 2203 vehicles, there is not a need for an enhanced crossing
at this location. Pavement markings with a crosswalk and appropriate signage is an appropriate
pedestrian treatment.
Conclusions and Recommendations
Recommendations based upon the Guidance for Uncontrolled Pedestrian Crossing Treatment Selection Process
and Matrix developed for the MDT and FHWA’s Guide for Improving Pedestrian Safety at Uncontrolled
Crossing Locations suggest that with present traffic volumes and speeds on West Babcock Street a
pavement marking crosswalk and signage is appropriate. It is also suggested to apply safety
countermeasures such as restricting parking on West Babcock in the approach areas to the
crosswalk. Sanderson Stewart does recommend that as future developments occur, the pedestrian
crossing treatment analysis should be revisited. If changes to the roadway connections of West
Babcock Street occur as predicted in the TMP, allowing this portion of roadway to operate as a
collector, speeds increasing, or as futured developments are established, we recommend revisiting
the most appropriate pedestrian crossing treatment at this location.
Please feel free to contact me at 406-922-4306 or jstaszcuk@sandersonstewart.com if you have any
questions or would like to discuss this further.
Sincerely,
Joey Staszcuk, PE, PTOE
Senior Engineer/Transportation Studio Manager
JHS/kpc
P:20156_Peds Warrant West Babcock_102220