Traffic Analysis Memo_Mesenbrink Federal Package_Chanhassen
1 | P a g e Mesenbrink Mixed Use, Mankato, MN
April 14, 2023
To: John Mesenbrink, Mesenbrink Construction
From: Vernon Swing, PE
Re: Traffic Analysis – Federal Package at Audubon Business Park, Chanhassen, MN
Per your request, SSTS LLC has conducted a traffic study for the Federal Package at Audubon Business Park
development (hereafter referred to as the Proposed Project) located to the west of Audubon Rd between
TH 5 to the north and Coulter Blvd to the south in Chanhassen, MN . This traffic study focuses on the
addition of traffic to local street system from two manufacturing buildings in the year 2024, one that is
proposed as 228,150 square feet (sf) and the other as 165,440 sf. The Proposed Project will be accessed via
two driveways from Coulter Blvd and via McGlynn Road. Figure 1, Vicinity Map, depicts the location. Figure
2, Site Plan, illustrates the site layout and access locations.
The study area for this memorandum has been identified through conversation with City staff and includes
the intersections listed below.
Galphin Blvd & TH 5
Galphin Blvd & Coulter Blvd
Coulter Blvd & Audubon Rd
Audubon Rd & McGlynn Rd
Audubon Rd & TH 5
Coulter Blvd & General Mills Access
Coulter Blvd & East Access
The existing AM and PM peak hour traffic conditions were documented in the traffic study completed by
Alliant Engineering for Excel Energy’s Chanhassen Service Center development. This study relies on the
accuracy of the analysis conducted by Alliant for the existing and 2024 Build conditions as the basis for our
background conditions. This analysis includes forecasts of the trip generation potential for the proposed
land uses and distribution of these trips through the study area. These trips are then added to the Alliant
Engineering 2024 Build forecasts to represent the 2024 Build conditions reflecting the Proposed Project.
(Relevant sections of the Alliant study are reproduced in this study for your convenience.)
Existing Conditions
The existing conditions of the roadways and intersection providing direct and indirect access to the
Proposed Project were documented and are noted in Table 1 (the descriptions reflect conditions adjacent to
the site).
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Table 1. Study Roadway Characteristics
Existing Traffic Volumes
AM and PM peak hour turning movement counts were conducted at the study area intersections in October
2022. The following notes the peak hour timeframes:
AM: 7:30 AM to 8:30 AM
PM: 4:00 PM to 5:00 PM
Exhibit 1 (from Xcel Study) illustrates the existing peak hour traffic volumes, and shows the lane
configuration and traffic control.
Traffic Operations
The operating conditions of transportation facilities, such as roadways, traffic signals, roundabouts and stop-
controlled intersections, are evaluated based on the relationship of the theoretical capacity of a facility to
the actual traffic volume on that facility. Various factors affect capacity including travel speed, roadway
geometry, grade, number of travel lanes, and intersection control. The current standards for evaluating
capacity and operating conditions are contained in Highway Capacity Manual1. The procedures describe
operating conditions in terms of driver delay represented as a Level of Service (LOS). Operations are given
letter designations with "A" representing the best operating conditions and "F" representing the worst.
Generally, level of service “D” represents the threshold for acceptable overall intersection operating
conditions during a peak hour. The Chart on the following page summarizes the level of service and delay
criteria for signalized and unsignalized intersections.
1 Highway Capacity Manual (HCM), Transportation Research Board, 6th Edition
Roadway Functional Class Typical Section Posted Speed AADT (Year)
TH 5 Minor Arterial 4-Lane Divided 55 mph 25,700 (MnDOT)
Galphin Blvd Minor Arterial 3 to 5-Lane Undivided 45 mph 5,700 (MnDOT)
Coulter Blvd Minor Collector 2-Lane Undivided 30 mph 1,920 (MnDOT)
Audubon Rd Major Collector 2 to 3-Lane Undivided 45 mph 3,740 (MnDOT)
McGlynn Rd Local Street 2-Lane Undivided 30 mph 418 (Estimated)
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For side street stop-controlled intersections special emphasis is given to providing an estimate for the level
of service of the minor approaches. Traffic operations at an unsignalized intersection with side street stop-
control can be described two ways. First, consideration is given to the overall intersection level of service.
This takes into account the total number of vehicles entering the intersection and the capability of the
intersection to support these volumes. Second, it is important to consider the delay on the minor
approaches, since the mainline does not have to stop. It is common for intersections with higher mainline
traffic volumes to experience increased levels of delay and poor level of service on the side streets.
A final fundamental component of operational analyses is a study of vehicular queuing, or the line of
vehicles waiting to pass through an intersection. An intersection can operate with an acceptable Level of
Service, but if queues from the intersection extend back to block entrances to turn lanes or accesses to
adjacent land uses, unsafe operating conditions could result. In this report, the Industry Design Standard
95th percentile queue length is used. The 95th Percentile Queue Length refers to that length of vehicle queue
that has only a five-percent probability of occurring during an analysis hour.
This study has utilized the industry current Synchro/SimTraffic software package (11 th Edition) to analyze the
Existing and 2024 Build conditions for the AM and PM peak hours. It is noted, the reported results are from
the aggregate of 10 SimTraffic simulations which use a random number generator to seed the network with
vehicles. These results reflect dynamic conditions and are more accurate for the non-roundabout
intersections than the results of the static analysis reported by Synchro. Due to the random number
generator results can sometimes show slightly better operations on minor movements under higher traffic
conditions when the intersections are operating well. This can be seen when delays and queues noted in the
Build Scenario are slightly less than the No-Build Scenarios.
Analysis Results – Existing Conditions
Tables 2 summarizes the results of the operational analysis for the Existing Conditions.
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Table 2 – Existing Operations
The results of the analysis of existing conditions indicate that each study area intersection currently
operates at overall LOS C or better during the AM and PM peak hours. Due to the long, coordinated cycle
along TH 5 moderate to long delay occurs on the side streets. However, the side street delay did not result
in excessive vehicle queuing, thus intersection capacity is not an issue requiring mitigation.
Future Conditions
As mentioned above, the future conditions are based on the Alliant traffic study for Xcel Energy. In their
study, the existing traffic volumes were grown by one percent per year from 2022 to 2024 and the
estimated traffic for the Xcel site was added to the grown up 2024 numbers to reflect the build conditions.
The 2024 Build conditions from the Xcel study is the baseline for our study upon which the traffic forecast
(trip generation estimates) for the Proposed Project is added to. Figure 3 summarizes the 2024 No-Build
conditions (including Xcel traffic)
Trip Generation and Distribution
The trip generation estimates reflect the land uses discussed for the Proposed Project including two
industrial buildings, one with a 228,150 sf footprint and the other with a 165,440 sf footprint. The volume of
vehicle trips generated by the Proposed Project has been estimated for the weekday AM and PM peak hours
and on a daily basis using the data methodology described in the Institute of Transportation Engineers’ Trip
Generation Manual 2, 11th Edition. ITE’s Land Use Codes corresponding to proposed is 140-Manufacturing.
It is noted there are two independent variables to estimate the trips, building size and number of
employees. In this case we chose building size as it resulted in a larger number of trips allowing us to
2 Trip Generation Manual, Institute of Transportation Engineers (ITE), 11th Edition
Overall LOS & Delay C 31.6 C 21.6
Worst Appro LOS & Delay E 73.9 (SB) D 41.3 (SBL)
95th Percentile Queue
Overall LOS & Delay A 4.4 A 3.3
Worst Appro LOS & Delay A 8.4 (EB) A 6.8 (WB)
95th Percentile Queue
Overall LOS & Delay A 2.3 A 2.5
Worst Appro LOS & Delay A 5.1 A 6.0 (EB)
95th Percentile Queue EB - 51' EB - 52'
Overall LOS & Delay A 2.8 A 2.7
Worst Appro LOS & Delay A 5.6 A 8.8
95th Percentile Queue EB - 55' EB - 51'
Overall LOS & Delay B 16.7 B 19.9
Worst Appro LOS & Delay F 87.3 (SB) E 66.6 (SB)
95th Percentile Queue
McGlynn Rd & Audubon Rd
(Side Street Stop)
EB - 261' EB - 245'
TH 5 & Audubon Rd (Signal)
Coulter Blvd & Galphin Blvd
(Side Street Stop)EB - 48' EB - 38'
TH 5 & Galphin Blvd (Signal)
Coulter Blvd & Audubon Rd
(Side Street Stop)
Intersection
EBT 296'
Existing
AM Pk Hr PM Pk Hr
Measure of Effectiveness (Delay in Sec and Queue in Ft)
Criteria
SBT - 238'
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analyze a more conservative condition. Table 3 summarizes the trip generation estimate for the Proposed
Project.
Table 3 - Trip Generation
As shown in Table 3, the Proposed Project will generate 268 trips (204 entering and 64 exiting) during the
morning traffic peak hour, 291 trips (87 entering and 204 exiting) during the evening traffic peak hour and
1,870 daily trips.
The new trips have been assigned to the surrounding roadways according to the existing traffic patterns,
and according to travel time forecasts from Apple Maps, and Google Maps. In general, the site traffic is
distributed to the study area as follows:
To/from the north 5 percent
To/from the west 30 percent
To/from the south 25 percent
To/from the east 40 percent
It is noted the site will generate the most traffic during shift changes, which may occur during non-peak
hours. However, to provide the most conservative analysis it is assume the shift changes occur during the
peak traffic times. Figure 4 illustrates the 2024 Build conditions including the Xcel traffic couple and
Proposed Project traffic.
Analysis Results – 2024 Build Conditions
Tables 4 summarizes the results of the operational analysis for the 2024 Build Conditions. Note the 2024
Build operations reflect the additional traffic associated with the annual growth rate applied to existing
traffic volumes and the Xcel Energy Chanhassen Service Center traffic. Additionally, the Build operations
include the new traffic forecast for the Proposed Project.
Trips Generated:
Enter Exit Enter Exit
Manufacturing Industrial 1 140 393,590 s.f.R 204 64 R 87 204 R 1,870
204 64 87 204
268Totals Trips
PM Peak Weekday
ADT
291 1,870
Land Use Type
Block
No.Land Use Code Size AM peak
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Table 4
2024 Build Traffic Operations
The results shown in Table 4 indicate the 2024 Build operations of the study area intersections are
acceptable with LOS C or better for overall operations. Similar to the existing conditions, moderate to
lengthy delay times for the side street movements at the TH 5 intersections is forecast due to the lengthy
coordinated traffic signal timing. Again, the anticipated vehicle queuing is short indicating that there are no
anticipated traffic capacity issues that would require mitigation.
Summary and Conclusions
The following provides a summary of the study, traffic operations and recommendations:
AM and PM peak hour traffic operations were analyzed for the Existing and 2024 Build conditions.
The Proposed Project will generate 268 trips (204 entering and 64 exiting) during the morning traffic
peak hour, 291 trips (87 entering and 204 exiting) during the evening traffic peak hour and 1,870
daily trips.
Results of the traffic analysis for Existing conditions during both the AM and PM peaks indicate
acceptable operations with minimal vehicle back-ups at adjacent intersections.
Overall LOS & Delay C 27.1 C 26.9
Worst Appro LOS & Delay EB - 20'56.6 (SB) E 57.9 (SB)
95th Percentile Queue
Overall LOS & Delay A 5.7 A 4.3
Worst Appro LOS & Delay C 21.9 (EB) C 15.1 (EB)
95th Percentile Queue
Overall LOS & Delay A 3.2 A 2.9
Worst Appro LOS & Delay A 6.5 (EB) A 7.4 (EB)
95th Percentile Queue EB - 58' EB - 69'
Overall LOS & Delay A 3.6 A 2.9
Worst Appro LOS & Delay A 8.8 (EB) A 9.5 (EB)
95th Percentile Queue EB - 63' EB - 77'
Overall LOS & Delay C 23.2 C 20.5
Worst Appro LOS & Delay D 48.0 (SB) E 55.4 (SB)
95th Percentile Queue
Overall LOS & Delay A 4 A 3.8
Worst Appro LOS & Delay A 7.3 (NB) A 6.3 (NB)
95th Percentile Queue NB - 55' NB - 71'
Overall LOS & Delay A 0.8 A 1.3
Worst Appro LOS & Delay A 4.4 (SB) A 5.6 (SB)
95th Percentile Queue
Coulter Blvd & West Access
Coulter Blvd & East Access
SB - 36' SB - 47'
EB - 276' WB - 264'
McGlynn Rd & Audubon Rd
(Side Street Stop)
TH 5 & Audubon Rd (Signal)
Coulter Blvd & Galphin Blvd
(Side Street Stop)WB - 59' EB - 58'
Intersection
Measure of Effectiveness (Delay in Sec and Queue in Ft)
Criteria 2024 Build
AM Pk Hr PM Pk Hr
TH 5 & Galphin Blvd (Signal)
EB - 315' EB - 251'
Coulter Blvd & Audubon Rd
(Side Street Stop)
7 | P a g e Federal Package at Audubon Business Park, Chanhassen, MN
Results of the traffic analysis for year 2024 for both the AM and PM peaks with the Proposed Project
indicate acceptable operations with minimal vehicle back-ups.
Attachments: Figures 1-4; Exhibit 1
(The Appendices with Synchro/Simtraffic Worksheets are available upon request.)
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Exhibit 1 (By Others)
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