HomeMy WebLinkAboutTCSP Oversight Committee Minutes (37)EXISTING TRAFFIC CONDITIONS
for the
TRANSPORTATION AND COMMUNITY SUSTAINABILITY PLAN
LAUREL, MONTANA
March 2000
Prepared by.
Graphics bv:
C?? C rftr = Bwge" Cumin Associates
TABLE OF CONTENTS
INTRODUCTION .............................................................
1 .....................1
.
2. 1978 TRANSPORTATION GOALS ................................. .....................1
ROADWAY SYSTEM AND FUNCTIONAL CLASSIFICATION ...... 4
3
. 4
3.1. Freeway ....................................................................................... ...........................
6
Arterial Streets .............................................................................
2
3 ...........................
.
.
Collector Streets ..........................................................................
3
3 ...........................6
.
.
Local Streets ................................................................................
4
3 ...........................7
.
.
4. EXISTING TRAFFIC CONDITIONS .................................................... 8
4.1. Existing Traffic Volumes ............................................................ ........................... 8
4.2. Existing Street Characteristics ..................................................... ...........................8
4.3. Railroads ...................................................................................... ...........................8
4.4. Irrigation Ditches ......................................................................... .........................12
4.5. Designated Truck Routes ............................................................ .........................12
4.6. School Bus Routes ....................................................................... .........................12
4.7. Direct Highway Access ............................................................... .........................12
TRAFFIC CONTROL ......................................................
5 ....................13
. 13
6. CRASH HISTORY ........................................................... ....................
7. INTERSECTION TRAFFIC CONTROL ......................... .................... 16
7.1. Intersection Operations ................................................................ .........................16
7.2. Alternative Configurations for Intersections ............................... .........................16
8. EVALUATION OF 1978 TRANSPORTATION GOALS ....................17
8.1. Overall Goal ............................................................................... ..........................17
8.2. Specific Goal #I ......................................................................... ..........................18
8.3. Specific Goal 42 ......................................................................... ..........................18
8.4. Specific Goal #3 ......................................................................... ..........................19
8.4.1. Arterial Streets-Existing Capacity .........................20
8.4.2. Arterial Streets-Future Need ............................................... .......................... 20
8.5. Specific Goal #4 ......................................................................... ..........................21
8.6. Specific Goal 45 ......................................................................... ......................... 21
9. CONCLUSIONS .................................................................................. 22
LIST OF FIGURES
FIGURE 1 -STUDY AREA & ROADWAY CLASSIFICATION 2
FIGURE 2 -1978 ROADWAY CONCEPT PLAN 3
5
FIGURE 3 -MDT ROADWAY CLASSIFICATION 9
FIGURE 4 - HISTORIC TRAFFIC VOLUMES 10
FIGURE 5 - HISTORIC TRAFFIC GROWTH RATE 1 I
FIGURE 6 - INTERSECTION TRAFFIC VOLUMES
LIST OF TABLES
TABLE 1: I-90 CRASH STATISTICS 14
TABLE 2: P-4 CRASH STATISTICS 14
TABLE 3: SUMMARY OF CRASH CHARACTERISTICS - CITY STREETS 15
TABLE 4: 1999 SIGNALIZED INTERSECTION LEVEL-OF-SERVICE 16
LIST OF APPENDICES
APPENDIX A RAW TRAFFIC COUNTS
APPENDIX B LAUREL SCHOOL DISTRICT BUS ROUTES
APPENDIX C HCS ANALYSES
APPENDIX D PROJECT COMMUNICATIONS
ii
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
1. INTRODUCTION
The City of Laurel, Montana received a Transportation and Sustainability Grant in the
summer of 1999. As part of the development of the Transportation and Community
Sustainability Plan (TCSP), this report assesses the existing roadway conditions and
operations in Laurel, located in Montana's Yellowstone County. Although other modes
of transportation are vital to the development of sustainable communities, this report
primarily defines the existing roadway system, as shown in Figure 1. Efforts by other
members of the TCSP's development team will address alternate modes of transportation.
2. 1978 TRANSPORTATION GOALS
Laurel developed a Transportation Plan as part of an overall Comprehensive Plan in
1978. The 1978 Transportation Plan for Laurel, Montana, developed by Leigh
Associates, has served and continues to serve the community for general planning needs.
Originally, the plan projected a consistent growth rate anticipated at 6 to 7 percent
annually. This growth rate has not been achieved. As a result, many of the needs and
recommendations identified in 1978 are still relevant.
Figure 2 shows the Roadway Concept Plan, originally identified in the 1978
Transportation Plan, including MDT's roadway classification system. The 1978
Transportation Plan developed the following overall transportation goal:
Provide a street system that will serve existing and future land uses, provide
increased mobility for present and future Laurel citizens, and enhance the overall
quality and livability of the city.
Specific transportation goals were identified as:
1. Overcome the significant barrier to travel formed by the BN railroad tracks and
yards.
2. Provide improved access to I-90.
3. Establish a basic grid of arterial streets which will provide alternative travel
routes and greater mobility of travel within the Laurel urban area as well a
providing a frame-work for future urban growth.
4. Designate a basic system of collector streets in Laurel, which will provide
primary access to the proposed arterial street system.
5. Investigate alternatives for improving travel on US 212 south of Laurel.
Laurel Airport Rd
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Laurel 2000 TCSP
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;- -- -_. - -- -Frank Rd - - _1000 0 1000 Feet
-------------------------
8
8
Existing Traffic Conditions
T a„rat - Trnnsnnrtatinn and Communitv Sustainability Plan
3. ROADWAY SYSTEM AND FUNCTIONAL CLASSIFICATION
This section discusses the roadway classifications defined in the 1978 Transportation
Plan and shown previously in Figure 2. Because much of the road system is under the
jurisdiction of the Montana Department of Transportation (MDT), traffic and safety data
will be defined within the MDT classification system identified in Figure 3.
3.1. Freeway
Interstate 90 (1-90), Montana's primary east-west interstate route bisects Laurel parallel
to the railroad mainline tracks and the Yellowstone River. 1-90 provides two lanes of
travel in both directions, with a median separation. As a freeway, the primary purpose of
1-90 is vehicle mobility at high travel speeds under free-flow conditions.
Three interchanges serve the Laurel area. The East Laurel interchange, 1-90 milepost
437, provides a diamond interchange with the Frontage Road which continues west to
Laurel on the north side of the interstate. At this interchange the Frontage Road is the
eastern continuation of Laurel's Main Street and is classified by MDT as Primary Route 4
(P-4) and old US Highway 10.
The Laurel interchange, at milepost 434, is a trumpet style interchange with all access on
the east side of the intersecting street, 1St Avenue. The interchange currently connects I-
90 to 1St Avenue with stop-sign control on the ramps. Conversations with MDT staff and
recent development studies in Laurel indicate a need to consider installation of traffic
signals at the ramp intersections. Recent developments along 1St Avenue, directly north
of the interchange, resulted in an increasing number of vehicle trips accessing the
commercial developments. The curbed median along 1St Avenue (south of the
interchange to north of 4th Street) restricts full access to and from these relatively high
traffic generators, with no alternate route available. Any reevaluation of traffic control
should also address the access to and from businesses, through the portion of 1St Avenue
with a median.
The West Laurel interchange, at I-90 milepost 431, provides a partial interchange at the I-
90 crossing over the mainline railroad tracks. Traffic can access I-90 to or from the west
only.
4
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Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
3.2. Arterial Streets
Arterial streets serve as the principal network for through traffic flow. The routes
connect areas of major traffic generation and important rural highways entering the city.
Arterial streets are defined as major traffic-carrying streets, which carry through traffic
over relatively long distances - generally at least two miles. Access may be restricted to
improve travel flow.
Based on the 1978 Transportation Plan by Leigh Associates, the following roads serve as
arterials:
1St Avenue, which is classified by MDT as Montana Secondary Highway 532 at
the north edge of town and as portions of Primary Route 4 and US 212
Main Street, which is classified by MDT as (portions of) Primary Route 4 and old
highway US 10 and US 212
3.3. Collector Streets
A collector roadway services traffic between major and local roadways. These streets are
used mainly for traffic movements within residential, commercial and industrial areas.
The 1978 Transportation Plan identifies the following streets as urban collector routes:
• Valley Drive
• 12th Street
• Maryland Lane
• 6th Street
• 1St Street
• Railroad Street
• South 4th Street
• South 6th Street
• Shannon Road
• 8th Avenue
• 5th Avenue
• Wyoming Avenue
• Alder Avenue (south of Maryland Lane)
• Yard Office Road (within the city limits)
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
The 1978 Transportation Plan identifies the following roadways as rural collector routes:
• Laurel Airport Road
• 12th Street (west of 8t" Avenue)
• 9th Street
• Maryland Lane (east of Alder Avenue)
• Round House Road
• South Frontage Road
• Railroad Street, west of the West Laurel interchange
• Frank Road
• 19th Avenue or Golf Course Road
• Alder Avenue (north of Maryland Lane)
• Yard Office Road
• Strauch Road
• Seitz-Ronan Road
3.4. Local Streets
Laurel's local streets provide a traditional grid street system throughout much of the
town. The grid is truncated by the railroad tracks, traveling in an east-northeast direction.
The interstate also travels in a northeasterly direction, south of and approximately parallel
to the railroad tracks.
The interstate separates a small section of southwest Laurel and much of the industrial
and manufacturing land uses from direct access to the remainder of the city. The
industrial areas utilize 1st Avenue to connect to Laurel. However, trains using the South
4th Avenue at-grade railroad crossing can isolate the residential portion of town.
Newer residential developments on the eastern edges of town are not following a
roadway grid network, but are based on longer east-west streets serving the residents.
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
4. EXISTING TRAFFIC CONDITIONS
4.1. Existing Traffic Volumes
The MDT provided the historical traffic counts for the area, shown in Figure 4. The
historical traffic counts were utilized to determine the traffic growth rate over the past six
years, shown in Figure 5. Traffic counts and calculated growth rates are contained in
Appendix A.
The growth rate trends vary greatly, with one segment of I-90 showing a decline in traffic
from 1992 to 1998 and other segments showing average annual increases over 3 percent.
Other members of the TCSP project team collected intersection turning movements in
November and December, 1999 and in January, 2000. These intersection counts, shown
in Figure 6, indicate the typical weekday conditions during the peak morning, mid-day
and evening conditions at the 1 st Avenue intersections with Main Street and with 1St
Street.
4.2. Existing Street Characteristics
The roadways within Laurel typically provide a minimum of two travel lanes with
parking along both sides of the curbed streets. Parking restrictions are located
intermittently.
Sidewalks are located along the majority of the streets serving the residential lots less
than one acre in size. The sidewalks typically provide a combination of detached and
attached walks along both sides of the street. Many walks are in marginal conditions
with breaks in the concrete and uneven traveling surfaces, often due to numerous curb
cuts.
4.3. Railroads
The Burlington Northern and Santa Fe (BNSF) railroad and the Montana Rail Link
(MRL) share tracks along this section of their mainline routes. Laurel is the location for
both a maintenance and a switching facility for the Burlington Northern system.
Additionally, a wye to the BNSF tracks to the north exists near the East Laurel
interchange (referred to locally as the Wye). A wye to the BNSF tracks to the south
exists near the intersection of Railroad Street and 1st Avenue (known as the South
Tracks).
The railroad tracks are generally at-grade, with the only roadway grade-separations
occurring at the 1St Avenue underpass and at the East Laurel interchange. At-grade
railroad crossings exist only at 5th Avenue (crossing the mainline tracks) and at Railroad
Street (on the wye to the south tracks) and at South 4 h Street (on the south track). South
of the Yellowstone River, public roads typically cross the railroad tracks at-grade with a
roadway underpass provided for US 212 south of the study area.
300
340
380
460
490
470 740
510 640
910 Laurel Airport Rd
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2,040 1,570 1,550 W N 4,690
1,980 1,490 1,670 4,320
2,160 1,700 1,480 180 810 4,160
1,990 - -- 1,900 110 900 4,140
2,120 840 130 970 4,550
1,350 140 970
12th so- 1,260 170 1,070
770
5 1,000 180 1,030
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6 290 1 380 Mar and Ln 000
6,370 Maryland Ln
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Laurel 2000 TCSP
10,350 0
6
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7
870
Figure 3
10,900 , 11 100 ,
14
9,040 9,1 0 n Frank Rd 1$'610 12,104400
12,410 a;g?
9,790 Traffic Volumes
Average Annual Daily Trips
--- 11,170 970 (Number of Vehicles Per Day )
520 11,920 N
1992
570 10,550 1993
630
580
199955 Numbers correspon
d
640 1000 0 1000 Feet 1996 to these years
830 1997
1998
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LAUREL 2000 TCSP
N Laurel Airport Rd
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Main Str (U.S. 10) East Railroad Str Round House Rd
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S. 4th Str S 21 151
111 168
143 239 156
\ 6 Str ' 42 T E-129 Laurel 2000 TCSP
? ,25 1 Figure 5
G 83 52
---- - -
87---4 E--80 Intersection Traffic Volumes
- ;22
t40 78 Legend
33-11 F, x-18 00 = AM Traffic Count
Frank Rd N !15 135 00 = Mid Day Traffic Count
18 231 30 PM Traffic Count
36
' Source: 1999 Traffic observations
1000 0 1000 Feet s 174
?? I See Appendix A
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
4.4. Irrigation Ditches
Numerous irrigation ditches exist within the study area, presenting a physical barrier for
roadways. The ditches generally flow from the west to the east and traverse the entire
length of the city, continuing eastward toward agricultural lands.
4.5. Designated Truck Routes
The MDT has designated the following routes as truck routes:
• Stn Avenue between Main Street and 12th Street, designated Urban Route U-
6905
• Railroad Street between lst Avenue and Shay Road, designated Urban Route
U-6902
No continuous truck route was found during research that designates an alternate railroad
crossing for 1St Avenue, Primary Route 4, where the railroad underpass provides a
substandard clearance. Primary Route 4 is also designated as an NHS route.
4.6. School Bus Routes
The Laurel School District supplied current data for bus route locations. These routes,
which vary to meet the transportation demands, are shown in Appendix B for the current
school year.
4.7. Direct Highway Access
Generally, the roadway network within Laurel has no access restrictions except as noted
below.
• I-90 is an access-controlled interstate with interchanges at Main Street and the
East Laurel interchange (with the frontage road). A partial interchange exists
at the west end of Laurel with connections to and from the west only.
• 1St Avenue, near the I-90 interchange, provides an intermittent, raised median.
The median extends south through the interchange and the Cenex refinery.
The raised median in the three-lane, commercial section north of the interstate
restricts left turn movements to/from the adjoining businesses.
Observations indicate that, occasionally, vehicles will still turn left by
traveling in the opposing lane through a short section of the raised median
roadway potentially creating extremely hazardous conditions for the traveling
public. In this area, the median prohibits full access to and from high traffic
generators. Lack of an alternate route encourages some vehicles to disregard
the roadway design and travel illegally to reach their destination.
12
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
5. TRAFFIC CONTROL
The majority of the local street intersections operate under the "yield to the right"
condition with no positive traffic control (no signs or signals designating the right-of-
way). Positive traffic control in Laurel primarily consists of stop-sign control on minor
streets at their intersections with major streets.
A two-phase traffic signal operates at the intersection of Main Street and 1St Avenue. A
flashing beacon is provided on Main Street, at its intersections with Yard Office Road (at
the eastern edge of Laurel) and with 5th Avenue (at the west end of Laurel).
Four-way stop conditions exist at the intersections of
• 1St Avenue and 1St Street
• 1St Avenue and West 6th Street (plus a four-way, flashing red beacon)
• West 6th Street and 8th Avenue
Railroad crossing gates are provided at the intersections with the following streets:
• 5th Avenue and Mainline Tracks
• South 0' Street and the South Track
Roadside flashing beacons are mounted on railroad cross-buck signs at the following
location:
• Railroad Street and the east leg of the wye to the South Tracks
6. CRASH HISTORY
The Montana Department of Transportation, Safety Management Section supplied the
most recent crash history (for years 1996-1998). These data are divided into segments
based on the MDT roadway classifications.
Comparative crash statistics are summarized in Table 1 for I-90. Table 2 contains the
crash statistics for the Primary Route #4 (originating in the study area as US 212,
continuing north on 1St Avenue until turning east at Main Street and continuing east to its
termination at the Mossmain interchange as US 212/Old Highway 10). Due to the NOT
roadway classification system, 1St Avenue, north of Main Street, is recorded under the
City Street classification. Table 3 summarizes repeated crash locations on City Streets
recorded over the study period.
The records indicate no crashes were recorded on Secondary 532 (Urban Route 6901) for
the section of the highway extending two miles north of the city limits. Fifty-nine
crashes were recorded in the three-year period on city streets. None of these crashes were
fatalities nor were any pedestrians involved (per NOT Accident Records).
13
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
Table 1: Interstate Crash Statistics: 1996 -1998
West of W. Laurel Laurel Mossmain Statewide
Interchange to Interchange to Interchange, Averages for
Laurel Mossmain extending 2 Rural
Interchan miles east Interstate
Mite st 431-434 434437 437-439
Crash Rate 1.87 1.20 1.08 1.18
Severity Index 2.36 2.31 1.98 2.15
Severity Rate 4.41 2.77 2.14 2.54
Total Number of 58 62 42
Crashes
Number of Fatal 1 0 0
Crashes
Number of Injurious 16 23 13
Crashes
Source: MDT Accident Records.
(1) Number of crashes per million vehicle-miles
(2) The ratio of the sum of fatal & incapacitating injury crashes times 8 plus the number of other
injury crashes times 3 plus the number of property damage crashes to the total number of
crashes
(3) Crash rate multiplied by the severity index
Table 2: Primary Route 4 (P-4) Crash Statistics: 1996 -1998
2 miles south of tst Avenue, Main Street, Main Street,
Laurel to Laurel I" Avenue to Yard Office Rd. Statewide
Averages
Laurel Interchange to Yard Office to Mossmain
Interchange Main Street Road Interchan e
Milepost 51-5 - 54.3 54.3-54.8 54.8-56.35 56.35-58,2
Crash Rate > 2.64 6.80 3.11 2.47 1.44
Severity Index 2.54 1.42 1.76 2.46 2.41
Severity Rate 6.71 9.66 5.47 6.08 3.47
Total Number of 57 38 (4) 29 (4) 24
Crashes
Number of Fatal 1 0 0 0
Crashes
Number of Inj. 23 8 6 10
Crashes
Source: MDT Accident Records.
(1) Number of crashes per million vehicle-miles
(2) The ratio of the sum of fatal & incapacitating injury crashes times 8 plus the number of other injury crashes times
3 plus the number of property damage crashes to the total number of crashes
(3) Crash rate multiplied by the severity index
(4) See Table 3 for additional details.
14
Existing Traffic Conditions
T a„rnl - Trnnsnortatinn and Communitv Sustainability Plan
Table 3: Summary of Crash Characteristics on City Streets: 1996 -1998
At Repeated Locations
Location Total Number Accident Type Number of Notes
of Crashes Injury
Crashes
I" Avenue & 12 crashes 7-rear end 3
Railroad Street 3-right angle
1g Avenue & 9 crashes 3-rear end 0 (1)
Main Street 3-left turn, opposite direction
US 212 @ Railroad 9 crashes 3 single vehicle hit guardrail, 3
overpass east of town 5 involved deceleratin turnin
1q Street &
3`d Street 6 crashes Not available 2
1" Avenue & 7 crashes Not available 2 (2)
Main Street
Source: NOT Accident Records.
(1) Recorded on P-4
(2) Recorded on City Streets
The crash rates and severity comparisons in Table 2 indicate that P-4 has a higher crash
rate and higher severity of crashes than other arterial roadways within the state. The
statewide averages, however, represent rural conditions and are not indicative of more
urban type development, such as occurs between the Laurel interchange and Yard Office
Road.
The Safety Management Section identified Hazard Elimination projects on the interstate
and primary roadways based on the recorded crashes. The interstate recommendations
are not restated herein, however the recommendations on the primary route are
summarized below:
• P-4, 52.3-52.8, 1997: Recommendation for speed plates on curve signs near
railroad overpass (south of town).
• P-4, 57.5-58.2, 1997: Recommendation for chevron signing on curve prior to
bridge and curve on bridge (bridge over railroad, east of town near East
Laurel Interchange).
• P-4, 55.3-56.0: Recommendation for extending two way left turn lane to
Locust Avenue. May not be programmed. (Alder to Locust)
• P-4: Recommendation for traffic signal pending warrant study on both
eastbound and westbound 1-90 ramps at intersection with P-4.
15
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
7. INTERSECTION TRAFFIC CONTROL
Level-of-Service (LOS) is a qualitative measure of traffic operating conditions for both
roadway segments and intersections using an alphabetic scale from A through F. LOS A
represents free-flowing traffic with minimal delay while LOS F represents congestion
with long periods of delay. LOS C is considered acceptable operations for rural
conditions on Montana state highways.
The existing, signalized intersection at Main and 1St Avenue is assumed to meet the signal
warrants in the Manual of Uniform Traffic Control Devices. The intersection appears to
operate acceptably for vehicles. Pedestrians, however, have a significant expanse of
roadway to cross (approximately 100 feet) and there are no provisions for pedestrians to
cross on the south leg. The southwest corner does not currently provide any pedestrian
access.
7.1. Intersection Operations
Based upon the peak hour traffic counts shown in Figure 6, Table 4 indicates the level-of-
service for the peak hours of the day. Level-of-Service computations are contained in
Appendix C.
Table 4: 1999 Signalized Intersection Level-of-Service
ti
n
I
t Movement rime-of Da
n
ersec
o AM Mid-Da PM
Main Streetll Avenue
Eastbound Left B C C
Through /Right C B B
Westbound Left B B B
Through B B B
Right B C C
Northbound Left A A A
Through /Right B B B
Southbound Left A A B
Through /Right B B B
Overall Intersection B B B
Highway Capacity Manual Worksheets are contained in Appendix C.
7.2. Alternative Configurations for Intersections
Alternate intersection control could be considered to provide less delay, increased
capacity and better conditions for pedestrian access. A roundabout could possibly be
designed to handle the existing traffic volumes, however significant physical changes
would be required and adequate signing/sight distance and pedestrian demands need to be
ensured. A roundabout may be considered at this location after collection of physical data
(site characteristics). Projected traffic volumes will need to be developed and evaluated
for any alternative configurations.
16
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
To provide system consistency for drivers and for the traffic system, a roundabout may
also be considered at other locations, if alternate intersection traffic control would
support non-motorized and motorized travel. As the TCSP is developed, intersection
control alternatives may be developed with criteria for selection based on the needs at any
given intersection.
8. EVALUATION OF 1978 TRANSPORTATION GOALS
This section presents a comparison of the current roadway system to the previously
established transportation goals. The goals are restated below in italics.
8.1. Overall Goal,
Provide a street system that will serve the existing and future land uses, provide
increased mobility for present and future Laurel citizens, and enhance the overall quality
and livability of the city.
The intent of the TCSP will support this goal with a stronger emphasis on non-motorized
transportation modes. This is an ongoing goal and is not defined as being "met" or
"unmet".
The overall goal of the Transportation and Community Sustainability Plan could be the
same as this goal with the addition underlined below to read as:
Provide a street system that will serve the existing and future land uses, provide
increased motorized and non-motorized mobility for present and future Laurel
citizens, and enhance the overall quality and livability of the city.
17
Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
8.2. Specific Goal #1.
Overcome the significant barrier to travel formed by the BNrailroad tracks and yard
The railroad tracks currently serve a fairly high volume of trains that constrains north-
south travel in Laurel. Current concerns center on:
• The only grade separation, the 1" Avenue underpass, is limited to two travel
lanes, with no shoulders, substandard vertical clearance, steep grades and
minimal sight distance. No additional vehicle capacity is available under
current conditions.
• The two at-grade crossings, 5t` Avenue and South 4 h Street, can be blocked
by trains for extended periods of time. Trains can block these at-grade
crossings simultaneously. The railroad would likely allow relocation of
existing crossings but would not encourage any additional at-grade crossings
due to the accident potential.
• Isolation of southwest corner of town when trains block both the 5t` Avenue
at-grade crossing and the South 4"' Street at-grade crossing, effectively
isolating the southwest residential section of town from both local access and
from emergency services. No alternate route currently exists to access this
portion of town.
This goal has not been met since its establishment in 1978. The tracks continue to
impede north-south travel in the area by restricting it to one, capacity-restricted underpass
and two at-grade crossings which maybe blocked simultaneously. Any future roadway
plans or improvements should encourage additional grade-separations of the railroad
tracks.
8.3. Specific Goal #2.
Provide improved access to I-90.
Laurel's access to regional roadways appears to be excellent with three interchanges
serving the area. However, the west interchange only serves traffic to/from the west,
which does not serve commuter travel or travel to/from businesses. Although the eastern
interchange serves commuter travel patterns and travel to/from businesses outside the
Laurel area, it does not effectively serve the business or residential sections of Laurel.
Therefore, the center interchange effectively best serves Laurel's business, commercial
and residential uses. This interchange may have additional roadway capacity (which may
be increased in the future by signalization), however it channels all traffic through the
existing I" Avenue railroad underpass with limited capacity and outdated design.
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Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
Therefore, regional access is primarily restricted to the Laurel interchange at 1St Avenue,
causing travel patterns to concentrate at the 1 s` Avenue railroad underpass, as the only
railroad grade separation to access the interstate. Additional commercial development
between the railroad underpass and the interchange has also increased the number of
turning vehicles in the area, reducing the through-vehicle capacity of 1St Avenue.
This goal has not been met. Construction of a new interchange is not likely, however
increasing the access to the existing interchanges would improve regional access to the
Laurel area.
This goal should be evaluated in the development of the TCSP to prioritize the need for:
• increasing capacity of the available accesses (expand 1St Avenue capacity) or
• decreasing travel demand on the available access (shift travel from 1St Avenue
to other interchanges) or
• increasing capacity of other accesses (expand West Laurel interchange and/or
East interchange) or
• lessening the emphasis of this goal to increase non-motorized opportunities in
the city.
8.4. Specific Goal #3.
Establish a basic grid of arterial streets which will provide alternative travel routes and
greater mobility of travel within the Laurel urban area as well a providing a frame-work
for future urban growth.
The existing arterial system in Laurel is comprised of Main Street and 1St Avenue. These
streets provide a backbone for the arterial system and generally provide acceptable traffic
operations under current traffic volumes and patterns except for sections of 1St Avenue.
Traffic flow on 1St Avenue is beginning to experience congestion due to commercial
growth between the interchange and the overpass and to limited capacity at the railroad
underpass. However, the need for additional arterial capacity to handle future growth is
increasing as growth occurs within Laurel and the surrounding area.
This goal was established in 1978 with no further implementation since then. The issue of
transportation sustainability is balancing land used for the street system with the livability
of the area. This goal may be reevaluated within the TCSP.
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Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
8.4.1. Arterial Streets-Existing Capacity
Adequate vehicle capacity exists on Main Street, with its wide right-of-way and
multi-lane configuration. The current traffic volumes would also operate
acceptably with two travel lanes, if adequate consideration were provided for
turning vehicles.
Ist Avenue, south of Main Street, currently carries considerably higher traffic
volumes than Main Street on fewer travel lanes. The capacity of 1St Avenue
between Main Street and the interchange is often less than the travel demand due
to three factors:
• Limited capacity of the two lane railroad underpass (outdated design
standards provide no shoulders and sub-standard sight distance and
grades)
• Substandard vehicle clearance in the railroad underpass restricts trucks
from utilizing this route
• High turning vehicle demand in the three-lane section between the
underpass and the interchange, based on recent commercial growth.
North of Main Street, traffic volumes decrease on 1St Avenue showing lower
travel demand. In this section, 1St Avenue provides adequate capacity for existing
traffic volumes via two travel lanes within a wide right-of-way. North of Main
Street, I" Avenue also provides a pleasant pedestrian environment due to
landscape buffers between the curb and sidewalk and parking along the roadway
and the general residential nature of the area.
The arterial roadway system needs to expand the capacity or lessen the demand
on 1" Avenue, between the interchange and the railroad underpass. Alternatives
may be developed as part of the TCSP.
8.4.2. Arterial Streets-Future Need
The TCSP needs to plan for additional arterial roads in the city, which would
support increased travel demand and also would provide alternate routes to attract
vehicles from existing arterials, potentially lessening the demand on the existing
arterials. Arterial spacing would support a north-south roadway on both the west
side and the east side of Laurel near the current city limits. Ideally these arterials
would have regional access, i.e., would connect to I-90.
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Existing Traffic Conditions
Laurel - Transportation and Community Sustainability Plan
The west side arterial should connect to the West Laurel interchange. The cross
street could be aligned due north of the current interchange or could shift to the
west to the approximate alignment of the Golf Course Road. However to ensure
continuity, any alignment along Golf Course Road should connect to the west
interchange and continue south of the interstate and railroad tracks, preferably
utilizing the existing structures. Connection to the 8"' Avenue overpass over the
interstate should be considered to improve access to the southwest residential
section.
An east-west arterial roadway also needs to be provided at the north edge of the
city to accommodate future growth. Based on current development patterns and
the location of the irrigation ditches, the Laurel Airport Road would be a good
location for the east-west arterial. The existing topography west of S 532 may
limit future development and therefore could terminate the proposed arterial
roadway. This termination and the proposed roadway section should coordinate
with development plans in future portions of the TCSP.
The section of Laurel south of the interstate needs an east-west arterial roadway
that is not blocked by railroad traffic to provide both local access and emergency
service access. Although future growth in this area does not seem as likely as
growth in the northern edges of town, the need to provide adequate access needs
to be weighted with regional priorities during the TCSP process.
8.5. Specific Goal #4.
Designate a basic system of collector streets in Laurel, which will provide primary access
to the proposed arterial street system.
Laurel's current system of collector roadways serves the existing residential land uses
well, with acceptable service to the manufacturing facilities south of the railroad tracks.
However, as residential growth continues, collector roadways need to be continually
planned to maintain connections to arterials and access to local land uses.
This goal was established in 1978 with no further implementation since then.
8.6. Specific Goal #5.
Investigate alternatives for improving travel on US 212 south of Laurel.
This goal has been met with the widening of US 212, south of the I-90 interchange
including reconstruction of the bridge over the Yellowstone River. This goal does not
affect travel within Laurel's city limits.
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Existing Traffic Conditions
i a„ra1 - Trmmnnrtntinn and Communitv Sustainabilitv Plan
9. CONCLUSIONS
The goals identified in the 1978 Transportation Plan still provide good direction for
transportation planning in the Laurel area. The general goal supports a sustainable
community, recognizing that quality and livability factors are influenced by the
transportation system. The specific goals still are applicable for Laurel's transportation
system but should be prioritized as part of the TCSP process.
The following general recommendations for Laurel's transportation system are based on
existing conditions (to be refined after consideration of future growth) and are
summarized below:
Retain Laurel's general grid street system, which encourages easy vehicular and non-
motorized access and mobility.
2. Maintain and expand the arterial street network so traffic can travel easily to
destinations and not seek alternate routes due to congestion.
Increase interstate access at Laurel's western limits to reduce the number of vehicles
using the 1St Avenue underpass. Improve roadway connectivity at the West Laurel
interchange.
4. Determine if increased access to the east Laurel interchange would benefit the
sustainability of the community.
5. Recognize that the 1st Avenue underpass is a bottleneck and influences traffic
operations both upstream and downstream. This bottleneck is a critical point because
no other grade separations are available.
6. Designate and plan for arterial and collector streets to ensure they are located in
advance of development and to provide continuity. Define and ensure connectivity to
the I-90 (the regional roadway network) for future arterial roadways.
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