5.1. PCSR Additional Information - Traffic Study Memo 9-25-22
1 | P a g e Scooters Coffee, Mankato, MN
September 25, 2022
To: Pat Briggs, The Briggs Companies
From: Vernon Swing, PE
Re: Traffic Study – Jackson Hills Apartments – Phase 2-4, Elk River, MN
Per your request, S2 Traffic Solutions, LLC has reviewed the traffic impacts associated with the
completion of phase 2-4 of the Jackson Hills Apartments (hereafter referred to as Proposed Project) in Elk
River, MN. The Proposed Project will complete 132 low-rise multi-family apartment units, and will be
accessed via 4 driveways, two from Jackson Ave NW and two from 6th Street NW, however, for the
purposes of this analysis the site access is assumed to occur at one location directly from Jackson Ave
NW. The site is located adjacent to the west side of Jackson Ave NW and is south of School St NW, and
for the purposes of this analysis the Proposed Project is expected to be fully occupied by 2025. (See
Attached Vicinity Map and Site Plan.)
To determine the impacts to the traffic capacity of Jackson Ave from the Proposed Project, traffic data
collected by MnDOT was acquired, the trip generation of the proposed use was forecast, and traffic
queuing analysis was conducted. This memorandum summarizes the findings.
Traffic Counts
The traffic data used in this study was acquired by S2 Traffic Solutions from MnDOT including AM and
PM peak hour turning movement counts at the intersections of Jackson Ave NW and TH 10, Jackson Ave
NW and TH 169, and School St NW and Freeport Ave NW. These counts were used to estimate the
existing traffic conditions at Jackson Ave NW and School St NW. The existing traffic volumes are shown
on the Figures Below. Also, the daily traffic volumes from MnDOT (5200 trips per day) on Jackson
Avenue near the site are used to identify the roadway capacity with and without the project.
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Existing AM Peak Traffic Existing PM Peak Traffic
Future Conditions
To quantify the impacts of a development on the surrounding roadway system, it is necessary to first
forecast and analyze traffic conditions that would be present on the roadway system without the inclusion
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of the proposed project. For this study, it is anticipated that the Proposed Project will be completed and
fully occupied by 2025. Review of historical traffic counts in the vicinity of the site suggest traffic has
declined over the last 20 years, however, to provide a conservative analysis this study assumes traffic will
grow at an annual rate of 0.5 percent through the 2025 design year. The figures below illustrates the No-
Build traffic volumes for year 2025 with the growth factor applied to existing traffic volumes.
2025 No Build AM Peak Traffic 2025 No- Build PM Peak Traffic
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Trip Generation and Distribution
The trip generation for the Proposed Project discussed in the introduction has been estimated based on the
methodology described by the Institute of Transportation Engineers (ITE) in Trip Generation, 11 th
Edition. The ITE land use code coinciding with the development is Code 220 for Low-Rise Multi-Family
Housing. Table 1 summarizes the findings.
Table 1
Trip Generation Forecast
Land Use AM Peak Hour PM Peak Hour Daily Trips Enter Exit Enter Exit
Low Rise Multi-Family (132 Units) 13 Trips 40 Trips 42 Trips 25 Trips 890 Trips
TOTAL 53 Trips 67 Trips 890 Trips
The ITE data indicates the Propose Project will generate 53 trips during the AM Traffic Peak, 13 entering
and 40 exiting, 67 trips during the PM Traffic Peak, 42 entering and 25 exiting, and 890 trips per day.
These trips were assigned to the local street network through a single access point onto Jackson Ave NW
to test the impact of a 100 percent concentration at one location (very conservative and not likely since
there are four driveways with the development).
The distribution of site traffic to area roadways is based on existing traffic patterns in the area and travel
times from Google Maps and Apple Maps. In general, 20 percent of site traffic is destined to/from the
north, 25 percent to/from the west and 55 percent to/from the south and east. The figures below illustrate
the trip assignment.
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AM Peak Trip Assignment PM Peak Trip Assignment
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The trip assignment shown above has been combined with the 2025 No Build Traffic volumes to generate
the 2025 Build traffic volumes shown on the Figures below.
2025 Build AM Peak Traffic 2025 Build PM Peak Traffic
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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 below summarizes the level of service
and delay criteria for signalized and unsignalized intersections.
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.
1 Highway Capacity Manual (HCM), Transportation Research Board, 6th Edition
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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 (11th Edition) to analyze
the 2025 No-Build and Build conditions for the AM and PM peak hours at the site access intersection,
and at the Jackson Ave NW intersections with School St NW and with TH 10. It is noted the site access
intersection is stop controlled and the other intersections are traffic signal controlled. The results of the
capacity analysis are summarized in Tables 2.
Table 2
Peak Hour Operations
The results shown in Table 2 indicate the overall operations of the study area intersections are providing
acceptable overall LOS with manageable vehicle queues for both the No-Build and Build conditions.
The roadway capacity conditions on Jackson Ave NW were also reviewed. In the vicinity of the site
Jackson Ave NW is generally a two-lane road with turn lanes at critical intersections which has a capacity
for approximately 15,000 trips per day. Currently Jackson Ave NW carries 5,200 trips per day or utilizes
approximately 35 percent of its capacity. The addition of the site traffic will add approximately 712 trips
per day in the southerly direction (greatest increase) increasing the daily traffic to approximately 5,912
trips per day. The addition of the new trips will change the roadway capacity usage to 39 percent. There
is sufficient capacity for future growth on Jackson Ave NW.
Conclusion
The proposed Jackson Hills Apartments Phase 2-4 to the Jackson Ave NW corridor will not result in poor
operations or excessive queuing at the study area intersections. Please contact Vernon Swing at
vswingtraffic@gmail.com or 612-968-4142 with any questions.
Attachments: Vicinity Map; Site Plan
LOS (Delay in sec) plus Vehicle Queuing in Feet
Intersection No. 2025 NB AM 2025 NB PM 2025 B AM 2025 B PM
Jackson Ave/TH10 C (24.1) C (22.7) C (25.9) C (21.9)
Worst Movement E (64.8) E (61.1) E (61.1) EBL E (64.5) WBL
95th Percentile Q EBT-445' WBL-480' EBT-519' WBT-461'
Jackson Ave/School St B (11.7) B (14.7) B (12.6) B (15.1)
Worst Movement C (25.8) EBL C (24.4) WBL C (21.1) WBT C (24.1) EBL
95th Percentile Q WBT-170' EBL-246' WBT-164' EBL-270'
Jackson Ave/Site Access A (2.3) A (3.1)
Worst Movement A (7.7) EBL A (6.4) NBL
95th Percentile Q EB-44' EB-43'
N/A N/A
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Vicinity Map
10 | P a g e Jackson Hills Apartments – Phases 2-4, Elk River, MN
Site Plan from Others