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Transportation Planning Study
Northwest Crossing
Tract 5 of Certificate of Survey 2552 | 5250 Baxter Lane
Bozeman, Gallatin County, Montana
August 2019
Prepared For:
NWX LLC
1735 South 19th Avenue
PO Box 11890
Bozeman, MT 59718
MMI Project No. 5659.004
Transportation Planning Study
Northwest Crossing | Bozeman, Gallatin County, Montana
Table of Contents | i
Table of Contents
Purpose of Report and
Study Objectives ................................... 1
Proposed Development ........................ 1
Location .......................................................... 1
Development Description ................................ 1
Development Horizon ...................................... 4
Development Traffic .............................. 4
Forecast Trip Generation ................................ 4
Trip Distribution ............................................... 5
Trip Assignment .............................................. 5
Pedestrians & Bicyclists .................................. 5
Transit Service ................................................ 5
Non-Site Traffic ............................................... 9
Method of Projection ......................................... 9
Estimated Volumes ........................................... 9
Total Traffic ..................................................... 9
Transportation Analyses .................... 12
Methodologies ............................................... 12
Study Scenarios .............................................. 12
Analysis Methodologies .................................. 12
Two-Way Stop-Controlled
(TWSC) Intersections .............................. 12
Roundabout Analyses .............................. 13
Traffic Operations .......................................... 13
Findings ............................................... 13
Need for Any Improvements ......................... 13
Mitigation of Baxter Lane & Laurel Parkway .. 19
All-Way Stop Control ............................... 19
Traffic Signal Warrant Analyses .............. 19
Roundabout Control ................................ 19
Mitigation of Baxter Lane & Cottonwood Road / Harper Puckett Road ...... 20
Pedestrians & Bicyclists ................................ 22
Transit Service.............................................. 22
Conclusions & Recommendations ... 22
Baxter Lane .................................................. 22
Cottonwood Road ......................................... 23
Laurel Parkway ............................................. 23
West Oak Street ........................................... 23
Baxter Lane & Laurel Parkway ..................... 24
Baxter Lane & Cottonwood Road / Harper Puckett Road .................................... 24
West Oak Street & Laurel Parkway ............... 24
West Oak Street & Cottonwood Road ........... 25
Interior Roadways & Intersections ................ 25
Pedestrian & Bicyclist Connectivity ............... 25
References ........................................... 26
Transportation Planning Study
Northwest Crossing | Bozeman, Gallatin County, Montana
ii | Appendices
Appendices
Appendix A
Trip Generation Analyses
Appendix B
Capacity & Level of Service Analyses
B-1: Intersection Operations Summaries
B-2: Estimated 2040 Background Traffic
B-3: Estimated 2040 Total Traffic
Appendix C
Signal Warrant Analyses
Appendix D
Mitigation Analyses
D-1: Estimated 2040 Background Traffic
D-2: Estimated 2040 Total Traffic
Appendix E
Level of Service Concepts, Analysis Methodologies, & Standards of Significance
Transportation Planning Study
Northwest Crossing | Bozeman, Gallatin County, Montana
List of Figures & Tables | iii
List of Figures
Figure 1: Project Location ................................................................................................................... 2
Figure 2: Preliminary Development Layout ....................................................................................... 3
Figure 3: Primary Trip Distribution ..................................................................................................... 6
Figure 4: External Site Traffic Assignment ........................................................................................ 7
Figure 5: Internal Site Traffic Assignment ......................................................................................... 8
Figure 6: Estimated 2040 Background Traffic ................................................................................. 10
Figure 7: Estimated 2040 Total Traffic at Exterior Intersections .................................................... 11
Figure 8: Estimated 2040 Background Traffic LOS Summary ........................................................ 14
Figure 9: Estimated 2040 Weekday, AM Peak Hour External Traffic LOS Summary ..................... 15
Figure 10: Estimated 2040 Weekday, PM Peak Hour External Traffic LOS Summary ................... 16
Figure 11: Estimated 2040 Weekday, AM Peak Hour Internal Traffic LOS Summary .................... 17
Figure 12: Estimated 2040 Weekday, PM Peak Hour Internal Traffic LOS Summary .................... 18
List of Tables
Table 1: Estimated Northwest Crossing Trip Generation Summary ................................................ 4
Table 2: 2040 Intersection Operations Summary for
Baxter Lane & Laurel Parkway with Roundabout Control .............................................................. 20
Table 3: 2040 Intersection Operations Summary for
Baxter Lane & Cottonwood Road / Harper Puckett Road
with the Addition of an Eastbound Right-Turn Lane ....................................................................... 21
Transportation Planning Study
for
Northwest Crossing
Bozeman, Gallatin County, Montana
Transportation Planning Study
Northwest Crossing | Bozeman, Gallatin County, Montana
1
Purpose of Report and Study Objectives
The intent of this transportation planning study is to assess traffic operations for the transportation
network shown in the Bozeman Transportation Master Plan (TMP) prepared by Robert Peccia &
Associates dated April 2017 and potential impacts with the proposed Northwest Crossing development
proposed to be located in Bozeman, Gallatin County, Montana. The information presented in this report
is intended to evaluate the safety and operational aspects of the transportation system in the area of the
proposed development under anticipated future conditions as well as with estimated impacts. Study
recommendations and conclusions are intended to provide guidance with respect to the short- and long-
term function of the area transportation system.
Proposed Development
Location
The proposed Northwest Crossing development is located in Bozeman, Gallatin County, Montana on
Tract 5 of Certificate of Survey No. 2552 located in the northeast quarter of Section 4, Township 2 South,
Range 5 East, Principal Meridian of Montana. Generally, the property is bordered by agricultural land to
the west, West Oak Street to the south, the Bozeman Sports Park and future Cottonwood Road to the
south, and Baxter Lane to the north. The project location is shown in Figure 1 on the following page.
Development Description
The Northwest Crossing project is proposed to consist of a mix of commercial and residential
development on a total net area of approximately 125 acres. The development is estimated to generate
a total of 11,792 average weekday trips as well as 629 weekday AM and 766 PM peak hour trips. Access
to and from the development is proposed to utilize connections on the adjacent transportation network:
Laurel Parkway to the west, Cottonwood Road to the east, Baxter Lane to the north, and West Oak Street
to the south. The preliminarily proposed site layout is shown in Figure 2 on page 3.
Zoning
The existing site is currently zoned REMU (Residential Emphasis Mixed-Use Zoning District) and B-2M
(Community Business District-Mixed) under the City of Bozeman’s zoning designations. Descriptions of
each of the zoning designations are provided on page 4.
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Northwest Crossing | Bozeman, Gallatin County, Montana
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Figure 1: Project Location
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Figure 2: Preliminary Development Layout
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Development Horizon
It is anticipated that the proposed Northwest Crossing development will progress over the course of the
next 10 to 15 years. In order to assess the functionality of the transportation network in the area of the
proposed development, this study will evaluate traffic operations through the year 2040, being in-line with
the analysis timeframe of the Bozeman TMP.
Development Traffic
Forecast Trip Generation
Trip generation is a measure or forecast of the number of trips that begin or end at the development site.
The traffic generated is a function of the extent and type of proposed development. This study utilized
Trip Generation, 10th Edition published by the Institute of Transportation Engineers (ITE) for estimating
average vehicle trip ends based on Land Use Code (LUC) 210 – Single-Family Detached Housing;
LUC 220 – Multifamily Housing (Low-Rise); and LUC 770 – Business Park. Trip ends are defined as a
single or one-directional travel movement with either the origin or the destination of the trip inside the
study site. The estimated primary purpose trip generation for the proposed Northwest Crossing
development is summarized in Table 1 below. Primary purpose trips are those where the site is the
primary origin or destination, which result in new trips on the roadway system. Detailed analyses for each
parcel shown (i.e. A, B, C/D/E, etc.) in Figure 2 on the previous page are provided in Appendix A.
Table 1: Estimated Northwest Crossing Trip Generation Summary
Parcels
Land Use
Type Units
Average Weekday Trips Average Weekday,
AM Peak Hour Trips
Average Weekday,
PM Peak Hour Trips
Enter Exit Total Enter Exit Total Enter Exit Tota
l
A, B,
C/D/E2,
& G2
Business Park
322,000 SF
Gross Floor
Area
2,002 2,002 4,004 79 50 129 62 74 136
C/D/E1,
F, G1, H,
I2, K, L,
& M
Multifamily
Housing
(Low-Rise)
504
Dwelling
Units
2,082 2,082 4,164 69 164 233 170 110 280
I1, J, N,
O, & P
Single-Family
Detached
Housing
342
Dwelling
Units
1,812 1,812 3,624 68 199 267 221 129 350
TOTALS = 5,896 5,896 11,792 216 413 629 453 313 766
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Trip Distribution
Trip distribution is the process of identifying the probable destinations, directions, and traffic routes that
development related traffic will likely affect. Various methods are available for estimating trip distribution,
including the analogy, trip distribution model, area of influence, origin-destination (O-D), and surrogate
data methods. This study utilizes the trip distribution model method based on data adapted from the
Bozeman TMP for the 2040 forecast travel demand model volumes. The primary trip distribution for the
proposed Northwest Crossing development is shown in Figure 3 on the following page.
Trip Assignment
The assignment of development related traffic provides the information necessary to determine the level
of site related impacts to the area roadway system and intersections. It involves determining the volume
of traffic and its movements within the transportation system. At a minimum, trip assignment must also
consider route choice, how the existing transportation system functions, and travel times to and from the
site. The resulting traffic assignment at the study area intersections for the proposed Northwest Crossing
development is shown in the following figures:
Figure 4: External Site Traffic Assignment – Page 7
Figure 5: Internal Site Traffic Assignment – Page 8
Pedestrians & Bicyclists
Facilities for pedestrians and bicyclists are proposed to be included as part of the Northwest Crossing
development in accordance with City of Bozeman standards. The Bozeman TMP recommends the
inclusion of bicycle lanes on Baxter Lane, Cottonwood Road, Laurel Parkway, and West Oak Street.
Shared-use pathways are also proposed to be included along Cottonwood Road and West Oak Street.
Transit Service
Streamline currently provides transit service to Belgrade, Bozeman, Four Corners, and Montana State
University. This service is currently free for all passengers, which creates an incentive for transit ridership.
Streamline does not currently offer any routes that provide service within the study area.
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Figure 3: Primary Trip Distribution
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Figure 4: External Site Traffic Assignment
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Figure 5: Internal Site Traffic Assignment
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Non-Site Traffic
Method of Projection
In order to more accurately reflect the potential impacts from development generated traffic it is necessary
to develop an estimate of non-site related traffic growth during the analysis period. Three primary means
are typically used to estimate growth of non-site generated traffic, including the build-up method, the use
of transportation plans or models, as well as the trends or growth rate method.
The build-up method takes into account traffic growth due to approved or anticipated to be approved
developments in the study area. Transportation plans or models typically provide estimates for traffic
volumes for approximately 20 years into the future. The model volumes are usually provided for average
weekday traffic, but can be converted to peak hour volumes including turning movements. The trends or
growth rate method involves evaluating the historic traffic growth rates within a study area. The underlying
assumption with this method is that historic growth trends will remain approximately the same and
continue in the future.
Estimated Volumes
Estimated background traffic volumes for the 2040 development horizon were established by utilizing
average weekday traffic volume projections contained within the Bozeman TMP. Estimated weekday,
peak hour turning movement volumes were derived by applying K factors to the 2040 annual average
daily traffic volumes in the Bozeman TMP to arrive at volumes for the AM and PM peak hours. K factors
are defined as being a proportion of annual average daily traffic occurring in an hour. A K factor of 0.096
(9.6%) was utilized for the weekday, AM peak hour, and a K factor of 0.103 (10.3%) was used for the
weekday, PM peak hour. Turning movement volumes were developed from the calculated total weekday,
AM and PM peak hours based on known traffic patterns in the surrounding area during those periods.
Estimated 2040 background traffic volumes are presented in Figure 6 on the following page.
Total Traffic
Site-generated traffic from the proposed Northwest Crossing development for full build-out conditions
was combined with the estimated 2040 background traffic volumes to establish the estimated 2040 total
traffic volumes that were used in the impact analyses. Those volumes are shown in Figure 7 on page 11.
Although there may be some cut-through traffic within the proposed development, the estimated 2040
total traffic volumes included as a part of this study are limited to the external intersections adjacent to
the proposed development.
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Northwest Crossing | Bozeman, Gallatin County, Montana
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Figure 6: Estimated 2040 Background Traffic
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Figure 7: Estimated 2040 Total Traffic at Exterior Intersections
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Transportation Analyses
Methodologies
This section documents the methodologies and assumptions used to conduct the traffic impact analyses
for the proposed Northwest Crossing development. Study methodology and analyses are based on ITE’s
Recommended Practices for Transportation Impact Analyses for Site Development. These analyses are
used to determine the project’s conformance with City of Bozeman policies and evaluate whether the
proposed development’s impacts are perceptible to the average driver.
Study Scenarios
This study presents analyses of the following scenarios:
Estimated 2040 Background Traffic Estimated 2040 Total Traffic
Analysis Methodologies
Transportation system operating conditions are typically described in terms of “level of service”. Level of
service (LOS) is the performance measure used to evaluate the cumulative effects of such things as
travel speed, traffic volumes, roadway and intersection capacity, travel delay, and traffic interruptions.
Operating conditions are designated as LOS A through LOS F, which represents the most favorable to
the least favorable operating conditions.
Level of service for intersections is determined by control delay. Control delay is defined as the total
elapsed time from when a vehicle stops at the end of a queue to the time the vehicle departs from the
stop line. The total elapsed time includes the time required for the vehicle to travel from the last-in-queue
position to the first-in-queue position, including deceleration of vehicles from the free flow speed to the
speed of vehicles in the queue. Appendix A lists the delay/LOS criteria listed in the Highway Capacity
Manual, 6th Edition | A Guide for Multimodal Mobility Analysis (HCM) published by the Transportation
Research Board (TRB) for unsignalized and signalized intersections.
Two-Way Stop-Controlled (TWSC) Intersections
Two-way stop-controlled (TWSC) intersection capacity and level of service analyses were performed
using HCS TWSC Version 7.4 developed and maintained by the McTrans Center at the University of
Florida. Unsignalized intersection analyses are based on Chapter 20 of the HCM. The HCM methodology
for evaluating TWSC intersections is based on gap acceptance and conflicting traffic for vehicles stopped
on the minor street approaches. The critical gap (or minimum acceptable gap) is defined as the minimum
time interval in the major street traffic stream that allows entry for one minor street vehicle. Average
control delay and LOS for the “worst approach” are reported. LOS is not defined for the whole intersection.
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Roundabout Analyses
Roundabout intersection capacity and level of service analyses were performed using HCS Roundabouts
Version 7.4 also developed and maintained by the McTrans Center. Roundabout intersection analyses
are based on Chapter 22 of the HCM. The HCM methodology for evaluating roundabout intersections is
based on flow patterns and conflicting traffic for vehicles entering, circulating, and exiting the roundabout.
Traffic Operations
Capacity and level of service analyses were performed for the study area intersections for each of the
study scenarios based on intersection geometry and traffic control proposed as part of the Bozeman TMP
for the future, 2040 transportation network. Detailed results of the analyses are provided in Appendix B
and are summarized in the following figures:
Figure 8: Estimated 2040 Background Traffic LOS Summary – Page 14
Figure 9: Estimated 2040 Weekday, AM Peak Hour External Traffic LOS Summary – Page 15
Figure 10: Estimated 2040 Weekday, PM Peak Hour External Traffic LOS Summary – Page 16
Figure 11: Estimated 2040 Weekday, AM Peak Hour Internal Traffic LOS Summary – Page 17
Figure 12: Estimated 2040 Weekday, PM Peak Hour Internal Traffic LOS Summary – Page 18
Findings
Need for Any Improvements
Capacity and level of service analyses for traffic conditions based on estimated 2040 background and
total traffic conditions identified the following intersections that may require some form of mitigation:
Baxter Lane & Laurel Parkway
Baxter Lane & Cottonwood Road / Harper Puckett Road
Each of the remaining intersections evaluated as a part of this study are projected to function at LOS C
or better on each approach, which is the minimum desirable level of service. Therefore, no additional
improvements are necessary to mitigate projected traffic operations for West Oak Street and its
intersections with Laurel Parkway or Cottonwood Road nor the conceptually proposed internal
intersections within Northwest Crossing for estimated 2040 background or total traffic conditions. Detailed
analyses of evaluated intersection traffic operations are provided in Appendix B.
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Figure 8: Estimated 2040 Background Traffic LOS Summary
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Figure 9: Estimated 2040 Weekday, AM Peak Hour External Traffic LOS Summary
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Figure 10: Estimated 2040 Weekday, PM Peak Hour External Traffic LOS Summary
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Figure 11: Estimated 2040 Weekday, AM Peak Hour Internal Traffic LOS Summary
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Figure 12: Estimated 2040 Weekday, PM Peak Hour Internal Traffic LOS Summary
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Mitigation of Baxter Lane & Laurel Parkway
As part of the Bozeman TMP, the proposed future intersection of Baxter Lane and Laurel Parkway is
conceptually configured for two-way stop control, all-way stop control, or signalized control. The initial
analyses for estimated 2040 background traffic conditions were based on two-way stop control, with stop
control installed on the northbound and southbound Laurel Parkway approaches. No analyses of the
future intersection were included as part of the final Bozeman TMP.
All-Way Stop Control
All-way stop control was initially evaluated for the intersection of Baxter Lane and Laurel Parkway;
however, it was found to degrade the projected traffic operations on Baxter Lane to LOS F for the
eastbound approach during the weekday, AM peak hour and LOS E for the westbound approach during
the weekday, PM peak hour. Therefore, all-way stop control was not considered a viable means of
mitigating substandard traffic operations for the intersection.
Traffic Signal Warrant Analyses
The intersection of Baxter Lane and Laurel Parkway was then evaluated for consideration of installing a
traffic signal. Because the estimated 2040 background and total traffic volumes are based on projections,
actual 24-hour traffic volumes, pedestrian / bicyclist crossings, and crash experience data are not
available to perform a full traffic signal warrant analysis. The Oregon Department of Transportation has
developed a procedure for preparing a preliminary signal warrant analysis based on estimated average
daily traffic volumes to evaluate “Warrant #1: Eight-Hour Vehicular Volume” and “Warrant #2: Four-Hour
Vehicular Volume” similarly to criteria outlined in the Manual on Uniform Traffic Control Devices published
by the Federal Highway Administration (June 13, 2012). Criteria are not evaluated for “Warrant #3: Peak
Hour” based on estimated average daily traffic volumes.
In performing the signal warrant analysis for the intersection of Baxter Lane and Laurel Parkway based
on estimated 2040 background and total traffic volumes, all right turn movements were excluded from
the analyses. The intersection is not projected to satisfy either Warrant #1 – Eight-Hour Vehicular Volume
or Warrant #2: Four-Hour Vehicular Volume for estimated 2040 background or total traffic volumes. The
signal warrant analyses are included in Appendix C.
Roundabout Control
Single-lane roundabout control was evaluated as an alternative for the intersection of Baxter Lane and
Laurel Parkway. Overall, the intersection is projected to operate at LOS A during both the weekday, AM
and PM peak hours for estimated 2040 background and total traffic conditions. The results of the
roundabout analyses are summarized in Table 2 on the following page and in Appendix D.
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Table 2: 2040 Intersection Operations Summary for Baxter Lane & Laurel Parkway with Roundabout Control
Analysis
Scenario Lane Group LOS
Delay
(sec/veh)
Entry
Volume
(veh)
Volume to
Capacity
Ratio
(v/c)
HCS 95% Max
Queue Length
(veh)
HCS 95% Max
Queue Length
(ft)
Estimated
2040
Background
Traffic
Weekday, AM
Peak Hour
Intersection A 8.1 1,007 0.40
EB LTR B 10.5 528 0.57 3.8 100
WB LTR A 5.4 282 0.27 1.1 50
NB LTR A 6.4 54 0.10 0.3 25
SB LTR A 5.3 143 0.17 0.6 25
Estimated
2040
Background
Traffic
Weekday, PM
Peak Hour
Intersection A 7.7 1,068 0.40
EB LTR A 4.6 430 0.16 0.6 25
WB LTR B 10.2 540 0.57 3.7 100
NB LTR A 4.5 130 0.14 0.5 25
SB LTR A 7.1 109 0.18 0.7 25
Estimated
2040 Total
Traffic
Weekday, AM
Peak Hour
Intersection A 8.9 1,123 0.44
EB LTR B 11.5 560 0.61 4.4 125
WB LTR A 6.1 329 0.33 1.4 50
NB LTR A 7.3 84 0.15 0.5 25
SB LTR A 5.9 150 0.20 0.7 25
Estimated
2040 Total
Traffic
Weekday, PM
Peak Hour
Intersection A 8.1 1,209 0.34
EB LTR A 4.6 430 0.16 0.6 25
WB LTR B 10.2 540 0.57 3.7 100
NB LTR A 4.5 130 0.14 0.5 25
SB LTR A 7.1 109 0.18 0.7 25
NB = Northbound; SB = Southbound; EB = Eastbound; and WB = Westbound | LTR = Left-Through-Right
Mitigation of Baxter Lane & Cottonwood Road / Harper Puckett Road
The proposed future intersection of Baxter Lane and Cottonwood Road / Harper Puckett Road is
conceptually configured for roundabout control with single lane entries for the eastbound and westbound,
Baxter Lane approaches and dual-lane entries on the northbound, Cottonwood Road approach as well
as the southbound, Harper Puckett Road approach as part of the Bozeman TMP. With the addition of
estimated traffic from the proposed Northwest Crossing development the eastbound, Baxter Lane
approach is projected to degrade to LOS D during the weekday, AM peak hour. The intersection was
evaluated with the addition of a dedicated, eastbound right-turn lane. The results of the analyses are
summarized in Table 3 on the following page and are provided in Appendix D.
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Table 3: 2040 Intersection Operations Summary for Baxter Lane & Cottonwood Road / Harper Puckett Road
with the Addition of an Eastbound Right-Turn Lane
Analysis
Scenario Lane Group LOS
Delay
(sec/veh)
Entry
Volume
(veh)
Volume to Capacity
Ratio
(v/c)
HCS 95% Max
Queue Length
(veh)
HCS 95% Max
Queue Length
(ft)
Estimated
2040
Background
Traffic
Weekday, AM
Peak Hour
Roundabout
Control
Intersection A 7.3 1,449 0.34
EB LT A 8.5 304 0.40 1.9 50
EB R A 8.2 337 0.41 2.0 50
WB LTR A 6.9 371 0.38 1.8 50
NB LT A 5.7 113 0.18 0.7 25
NB TR A 6.6 228 0.26 1.0 25
SB LT A 5.2 49 0.07 0.2 25
SB TR A 5.1 47 0.07 0.2 25
Estimated
2040
Background
Traffic
Weekday, PM
Peak Hour
Roundabout
Control
Intersection A 8.8 1,538 0.40
EB LT A 6.6 215 0.27 1.1 50
EB R A 6.2 225 0.26 1.1 50
WB LTR B 13.2 529 0.64 4.8 125
NB LT A 6.2 248 0.28 1.1 50
NB TR A 6.6 269 0.31 1.3 50
SB LT A 6.6 25 0.05 0.2 25
SB TR A 6.7 26 0.05 0.2 25
Estimated
2040 Total
Traffic
Weekday, AM
Peak Hour
Roundabout
Control
Intersection A 8.1 1,601 0.38
EB LT A 8.5 304 0.40 1.9 50
EB R A 8.2 337 0.41 2.0 50
WB LTR A 6.9 371 0.38 1.8 50
NB LT A 5.7 113 0.18 0.7 25
NB TR A 6.6 228 0.26 1.0 25
SB LT A 5.2 49 0.07 0.2 25
SB TR A 5.1 47 0.07 0.2 25
Estimated
2040 Total
Traffic
Weekday, PM
Peak Hour
Roundabout
Control
Intersection B 11.0 1,721 0.46
EB LT A 7.6 245 0.33 1.4 50
EB R A 6.8 240 0.29 1.2 50
WB LTR C 18.0 611 0.75 7.3 200
NB LT A 6.8 264 0.31 1.3 50
NB TR A 7.3 301 0.35 1.6 50
SB LT A 7.5 25 0.06 0.2 25
SB TR A 7.6 35 0.07 0.2 25
NB = Northbound; SB = Southbound; EB = Eastbound; and WB = Westbound
LT = Left-Through; R = Right; LTR = Left-Through-Right; and TR= Through-Right
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Pedestrians & Bicyclists
Facilities for pedestrians and bicyclists are proposed to be included as part of the Northwest Crossing
development in accordance with City of Bozeman standards. The Bozeman TMP recommends the
inclusion of bicycle lanes on Baxter Lane, Cottonwood Road, Laurel Parkway, and West Oak Street.
Shared-use pathways are also proposed to be included along Cottonwood Road and West Oak Street.
Transit Service
Streamline currently provides transit service to Belgrade, Bozeman, Four Corners, and Montana State
University. This service is currently free for all passengers, which creates an incentive for transit ridership.
Streamline does not currently offer any routes that provide service within the study area. Routes may be
added in the future as service expands within the Gallatin County area.
Conclusions & Recommendations
Analysis of trip generation estimates, site circulation, and traffic operations reveal that the proposed
Northwest Crossing development is projected to have limited impact on the area transportation system
as currently proposed through the Bozeman Transportation Master Plan. If the below improvements are
implemented as recommended, any impacts resulting from the proposed development should operate
safely and efficiently. All traffic control improvements should be installed in accordance with City of
Bozeman and the Manual on Uniform Traffic Control Devices standards.
Baxter Lane
Bozeman TMP Recommended Improvements:
Single travel lanes in both the eastbound and westbound directions;
Center two-way left-turn lane; and
Bicycle lanes plus boulevard sidewalks on both sides of the roadway.
These improvements are recommended to be installed prior to full build-out of the proposed Northwest Crossing
development between Laurel Parkway and Cottonwood Road / Harper Puckett Road; however, the roadway
geometry is intended to accommodate significant background traffic growth in the area and is not directly attributable
to traffic from the proposed Northwest Crossing development.
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Cottonwood Road
Bozeman TMP Recommended Improvements:
Two travel lanes in both the northbound and southbound directions;
Median or a two-way left-turn lane;
Bicycle lanes on both sides of the roadway;
A shared-use pathway on the east side of the roadway; and
Boulevard-style sidewalk on the west side of the roadway.
These improvements are recommended to be installed prior to full build-out of the proposed Northwest Crossing
development between West Oak Street and Baxter Lane; however, the roadway geometry is intended to
accommodate significant background traffic growth in the area and is not directly attributable to traffic from the
proposed Northwest Crossing development.
Laurel Parkway
Bozeman TMP Recommended Improvements:
Single travel lanes in both the northbound and southbound directions;
Center two-way left-turn lane; and
Bicycle lanes plus boulevard sidewalks on both sides of the roadway.
These improvements are recommended to be installed prior to full build-out of the proposed Northwest Crossing
development between West Oak Street and Baxter Lane; however, the roadway geometry is intended to
accommodate significant background traffic growth in the area and is not directly attributable to traffic from the
proposed Northwest Crossing development.
West Oak Street
The Bozeman TMP does not specify a recommend typical section for West Oak Street between Laurel Parkway and
Cottonwood Road as was done for the other roadways included as a part of this study; however, the roadway is
designated as a principal arterial as part of the Bozeman TMP.
This study evaluated West Oak Street as transitioning from a two lane roadway with a center, two-way left-turn lane
at Laurel Parkway to a four lane roadway with a raised median at Cottonwood Road. The following improvements are
recommended for the corridor to accommodate estimated 2040 traffic volumes:
West Oak Street – Laurel Parkway to Rosa Way:
o Dedicate minimum necessary width to allow for future 120 foot principal arterial right-of-way with the
Northwest Crossing development;
o Total roadway width equal to 82 feet from top-back of curb to top-back of curb;
o Eleven foot (11’) wide single travel lanes in both the eastbound and westbound directions separated by a
33 foot wide raised median with left turn lanes provided at appropriate intersections;
o Five foot (5’) wide bicycle lanes on both sides of the roadway with eight foot (8’) wide emergency
parking / snow storage lanes;
o A 12.5 foot wide boulevard with a 10 foot wide shared-use path on the north side of the roadway; and
o A 7.5 foot wide boulevard with a six foot (6’) wide sidewalk on the south side of the roadway.
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West Oak Street – Rosa Way to Cottonwood Road:
o Dedicate minimum necessary width to allow for future 120 foot principal arterial right-of-way with the
Northwest Crossing development;
o Total roadway width equal to 82 feet from top-back of curb to top-back of curb;
o Transition to and from single travel lanes in both the eastbound and westbound directions, allowing for an
11 and a 12 foot wide travel lane in each direction separated by 20 foot wide raised median / turning lane;
o Seven foot (7’) wide emergency parking / bicycle lanes on both sides of the roadway;
o A 12.5 foot wide boulevard with a 10 foot wide shared-use path on the north side of the roadway; and
o A 7.5 foot wide boulevard with a six foot (6’) wide sidewalk on the south side of the roadway.
These improvements are recommended to be installed prior to full build-out of the proposed Northwest Crossing
development between Laurel Parkway and Cottonwood Road; however, the roadway geometry is intended to
accommodate background traffic growth in the area and is not directly attributable to traffic from the proposed
Northwest Crossing development.
Baxter Lane & Laurel Parkway
Single-lane roundabout control is recommended for the intersection of Baxter Lane and Laurel Parkway based on
estimated 2040 background and total traffic volumes.
The intersection should be evaluated for the appropriate design vehicle per AASHTO standards with a recommended
minimum of a WB-62 (Interstate Semitrailer).
Baxter Lane & Cottonwood Road / Harper Puckett Road
Roundabout control is recommended for the intersection of Baxter Lane and Cottonwood Road / Harper Puckett Road
based on estimated 2040 background and total traffic volumes in accordance with the Bozeman Transportation Master
Plan with the following geometry:
Dual entry lanes on the northbound and southbound approaches as per the Bozeman TMP –
(1) left-through lane and (1) through-right lane;
Dual entry lanes on the eastbound approach – (1) left-through lane and (1) right turn bypass lane; and
Single entry lane on the westbound approach – (1) left-through-right lane.
The intersection should be evaluated for the appropriate design vehicle per AASHTO standards with a recommended
minimum of a WB-62 (Interstate Semitrailer).
West Oak Street & Laurel Parkway
Two-way stop control is recommended for the intersection of West Oak Street and Laurel Parkway based on estimated
2040 background and total traffic volumes with the following geometry:
Dual entry lanes on each approach – (1) left turn lane and (1) through-right lane and
Stop control installed on the northbound and southbound, Laurel Parkway approaches.
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Northwest Crossing | Bozeman, Gallatin County, Montana
25
West Oak Street & Cottonwood Road
Roundabout control is recommended for the intersection of West Oak Street and Cottonwood Road based on estimated
2040 background and total traffic volumes in accordance with the Bozeman Transportation Master Plan with the
following geometry:
Dual entry lanes on each approach as per the Bozeman TMP – (1) left-through lane and (1) through-right lane;
The intersection should be evaluated for the appropriate design vehicle per AASHTO standards with a recommended
minimum of a WB-62 (Interstate Semitrailer).
Interior Roadways & Intersections
Each of the interior intersections is projected to function acceptably as uncontrolled based on the traffic projections
included as a part of this study.
To limit the potential for impacts resulting from cut-through traffic between Baxter Lane and West Oak Street as well
as Laurel Parkway and Cottonwood Road, the central intersection within Northwest Crossing (noted as Node 11 in
Figure 5 on page 8) is recommended to be installed with mini roundabout control as a traffic calming measure. Mini
roundabout control may be considered for the remaining primary, internal intersections as desired for additional traffic
calming measures within the development.
Adequate sight distance in accordance with City of Bozeman standards, at a minimum, should be preserved at the
interior intersections within the proposed Northwest Crossing development.
On-site roadways should be constructed to City of Bozeman standards, at a minimum.
All intersections and radius returns for asphalt and/or curb and gutter should be evaluated for the appropriate design
vehicle per AASHTO standards. At a minimum, it is recommended that the largest fire vehicle utilized by the City of
Bozeman or school bus (as necessary) be utilized as the basis for design.
Pedestrian & Bicyclist Connectivity
Sidewalk and/or trail improvements should be constructed to City of Bozeman standards, at a minimum.
Transportation Planning Study
Northwest Crossing | Bozeman, Gallatin County, Montana
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References
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1 and 2. Washington DC: Author.
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