SR-164 Corridor Study
Introduction
With the assistance of UDOT Region #3, Payson City, Salem City, Spanish Fork City, MAG staff, and Utah County staff this corridor study identifies future traffic and development impacts to the SR-164 corridor from 2200 West (just west of I-15) to SR-198 (Main Street). This study proposes a recommended corridor concept with cross sections, active transportation plan updates, corridor preservation recommendations, safety improvements from a crash analysis, a short-term and long-term implementation plan and a cost estimate based on UDOT’s latest 2024 construction bids.
Large amounts of development pressure is occurring along the SR-164 Corridor on the border of Salem and Spanish Fork with likely potential impacts to the roadway system and I-15 interchange. As shown in the image to the right, Spanish Fork is expect to grow from a current population of 42,001 to 95,818 by 2050 and Salem is expected to grow from 10,146 to 55,829 by 2050.
Recommended Corridor Concept
WCG has evaluated the SR-164 Corridor from 2200 West to SR-198 and has developed a preferred roadway concept layout that shows the preferred number of lanes, interchange type, and intersection control necessary to provide adequate levels of service for the future planning year in 2050.
7- Lane Section
Salem City Cross Section
5- Lane Section
Spanish Fork Cross Section
Salem City Cross Section
SR-164 Corridor Concept
Download Roadway Concepts
Utah County Public Works has been working with the adjacent landowners to determine an alignment of 1600 West (Spanish Fork) / Loafer Mountain Parkway (Salem) north of SR-164 that is as least impactful as possible. Coordination will continue as roadway planning efforts progress.
Traffic Analysis
WCG has conducted a traffic analysis examining Existing (2024), Future (2034) and Future (2050) conditions to determine the appropriate number of lanes, interchange type, and intersection control necessary to provide adequate levels of service.
Access Management
The Transportation Research Board defines access management as “the systematic control of the location, spacing, design, and operation of driveways, median openings, interchanges, and street connections to a roadway” (TRB Access Management Manual, 2nd Edition, 2014). Access management has been documented to include the following safety and operational benefits:
Lower crash rates
Less severe crash severity
Increased traffic signal efficiency
Decreased delay
Increased capacity
UDOT Classifies SR-164 as an Access Category 4 – Regional-rural importance roadway, which is to meet the following access spacing requirements. The adjacent map shows which accesses do or do not meet current access spacing standards.
The map on the right shows the proposed build-out intersection spacing and control type for the SR-164 corridor necessary to meet UDOT Access Category 4 – Regional-rural importance roadway spacing standards (listed above).
As adjacent development occurs and as opportunities arise, the Cities, Utah County, and UDOT Region #3 should continue to work to consolidate accesses to meet spacing requirements.
Access Management Recommendation:
- Update the corridor agreement with a focus on consolidating accesses as the adjacent land develops.
Active Transportation
Active transportation includes any form of non-motorized transportation such as walking or biking. The map below shows existing planned active transportation improvements in the study area. As shown, a robust shared-use path network is planned on the corridor and the surrounding area.
One major challenge for active transportation facilities along SR-164 is the difficulty of crossing major intersections, such as Loafer Mountain Parkway and the I-15 interchange. The intersection at SR-164 and Loafer Mountain Parkway is expected to carry heavy vehicle volumes and will be a lengthy pedestrian crossing. While shared-use facilities are planned on all legs of this intersection, careful consideration is needed to ensure the safety and convenience of active transportation users. Pedestrian crossings at the I-15 interchanges will likely require a pedestrian overpass or underpass to comfortably accommodate active transportation users. When planning for designing the corridor it will be essential to accommodate active transportation crossings.
SR-164 & SR-198 intersection looking west
Active Transportation Recommendations:
- [#1] Salem and Spanish Fork to coordinate active transportation plans along city borders - Existing plans show bicycle facilities terminating at the border with Spanish Fork, such as on Loafer Mountain Parkway.
- [#2] Evaluate the feasibility of grade separated crossings at the I-15 interchange - Loafer Mountain Pkwy, 1200 West (Spanish Fork), and Mill Road to be constructed in conjunction with the roadway improvements. Emphasis is to be placed on regionally significant active transportation corridors.
Safety
The most recent six full years of available crash data (January 1, 2018 to December 31, 2023) from UDOT Traffic & Safety were used to perform a safety analysis within the study area. Historic crash patterns were analyzed to develop project recommendations.
Crash severity is reported according to a five-category scale ranging from no injury to fatality. UDOT, like many other places, has taken on the goal of Zero Fatalities . This zero fatalities approach is guided by the Safe System framework. The Safe System approach consists of the following five elements.
FHWA Safe System Approach
Key Takeaways:
The only discernible trend in crash data along the corridor was identified at the SR-164 / I-15 Southbound Ramp intersection. Since the installation of a traffic signal at the intersection in 2021, there have been fewer intersection crashes and no fatal or serious injury crashes. Prior to the installation of the signal there was a fatality and two possible injury crashes.
All Crashes (2018 - 2023)
There were 155 reported crashes recorded between 2018 and 2023.
Severe Crashes (2018 - 2023)
There were 6 suspected serious injuries and 2 fatalities between 2018 and 2023.
SR-164 / I-15 Southbound Ramp Intersection
There was one fatality at the SR-164 / I-15 Southbound Ramp in 2018 with a left turn conflict involving a motorcycle. This was the only fatal crash documented since 2010.
Since the signal was installed in 2021 there were:
- 18 reported crashes
- 13 property damage only
- 2 minor injury
- 3 possible injury
- Fewer southbound front to rear crashes
- No fatal or serious injury crashes
Regarding westbound left turning and eastbound through vehicle movements and using 2018 to 2023 data:
- Prior to the installation of the signal in 2018, there was a fatality and two possible injury crashes
- From 2021 to 2022, all five crashes resulted in property damage only
- In 2023, there were two crashes
- One possible injury
- One suspected minor injury
Corridor Preservation
Corridor Preservation Recommendation:
- Use the local government development approval process to acquire right of way.
- Coordinate with MAG and UDOT Region 3 on both the local corridor preservation process and the UDOT Statewide corridor preservation process.
Implementation Plan
Cost Estimate
The cost estimate provided is based on UDOT’s latest 2023 pricing estimates.
