Utah Department of Transportation

A UDOT Project

Overview

As part of its mission to improve quality of life through transportation, the Utah Department of Transportation (UDOT) has initiated an environmental study along the I-15 corridor between Farmington and Salt Lake City.

In the Alternative Development Phase the team identified multiple alternatives along the I-15 corridor and in the surrounding communities and invited the public to learn about and comment on these alternatives.

Following the comment period (November 10, 2022 – January 13, 2023), we reviewed each of the more than 2,800 comments. Based on this feedback and additional technical evaluation, we have prepared an Alternatives Screening Report, which is posted directly below. We’ve also provided answers to frequently asked questions and themes taken from the comments. Updated design maps are also now available.

If you have any questions please contact the study team.

Let Your Voice Be Heard

Public Comment Period: November 10, 2022-January 13, 2023
Your comments will help the study team gain insight into how these alternatives could serve you and your community. While you can contact the project team any time during the study, official comments for this phase of the study must be received no later than January 13.
Ways to Comment
  • Comment directly on the maps. (Click on the image to the right to open the map)
  • Use the comment form below.
  • Send us an email to i15eis@utah.gov with your idea or comment.
  • Comment by mail: 392 E Winchester St., Ste. 300, Salt Lake City, UT 84107
What should I comment on?
  • Which alternatives address safety in areas/ways you care about?
  • Are there safety issues you don’t see addressed in the alternatives?
  • Do these alternatives help to better connect you to the places you want to travel?
  • Which alternatives best align with how you see the future of transportation in your area?
  • What do you think of the trade-offs between the two I-15 options?
  • Are there walking and biking connections you saw that work better than others?
  • Were there improvements/connections you hoped to see that you didn’t?
Interactive Alternatives Map

Use the interactive map to learn about the alternatives, then make comments directly on the map.

Comment Form

Alternatives Development and Screening Report

This report describes the alternatives development and screening process we used to develop options to address the needs on I-15 and the surrounding communities. In addition to information about how options were developed, the report also contains a description of how they were analyzed, which are being carried forward for further study and which are being eliminated from further review, and why. It also contains a record of public comment from the Draft Alternatives Screening Comment Period, which was conducted between November of 2022 and January of 2023.

Because detailed work on the options and potential impacts is ongoing, the report does not contain the fully engineered and refined alternatives, their final impacts, cost evaluations or final recommendations. The report is meant as an update for stakeholders about the current status of the options. 

Detailed alternatives will be available in Fall 2023 in the Draft Environmental Impact Statement (EIS). That will be the next opportunity for the public to give us feedback during a public comment period and hearing we will hold at that time.

Download the Alternatives Development and Screening Report (PDF)

Frequently Asked Questions

The questions and comments below were submitted to the Utah Department of Transportation (UDOT) during the November 10, 2022 through January 13, 2023, draft alternatives screening public comment period for the I-15 Farmington to Salt Lake City Environmental Impact Statement (EIS). These reflect the topics most frequently heard in the recent comment period.

Process Questions

Primary Response

  • We read all the comments and consider them as part of the overall analysis of transportation options. This analysis includes technical and environmental considerations, compatibility with current and future plans, and input from a variety of stakeholders, including the public.


Detailed Response

  • At the conclusion of the Alternatives Phase comment period, our team read every comment received and categorized each according to common categories and themes. Some of those themes have received responses in this document. A summary of the comments is contained in Appendix D of the Screening Report.
  • Public comment is one factor in the overall analysis of proposed transportation improvements. This analysis includes assessment of technical, regulatory, environmental and social factors and potential impacts, along with public comment. Given that public comment is one factor balanced among many other considerations, public comment is not a vote, meaning that if one alternative gets a lot of positive comments and another received a lot of negative, other consideration may still suggest moving forward with an option less preferred as indicated by comments received.
  • At this stage of the EIS process, comments will not receive an individual response. After the Draft Environmental Impact Statement (DEIS) hearing and comment period, categorized comments will receive a response from our team.

Primary Response

  • Ultimately, UDOT will make the final determination of what – if any – project moves forward within the study area. The public will have a chance to weigh in again when we release the Draft Environmental Impact Statement (DEIS), which will include additional detail on impacts and further analysis. The DEIS release will include a public hearing and comment period.


Detailed Response

  • The next step in the process is the release of a Draft Environmental Impact Statement (DEIS), which is planned for fall 2023. That release will include a public hearing and a public comment period.
  • Following the comment period, UDOT will assess and respond to comments and prepare and release a Final Environmental Impact Statement (FEIS). A final decision on the path forward will then be recorded in a Record of Decision (ROD) that, once signed, is the final approval for a project to proceed.

Primary Response

  • Funding for both the current Environmental Impact Statement and the potential construction of any improvements approved as part of the environmental study have been provided by the State of Utah.


Detailed Response

  • Existing State funding is supporting the current Environmental Impact Statement (EIS) effort.
  • State transportation funding has been allocated for future construction, pending environmental approval.

Primary Response

  • The Alternatives Development and Screening Report documents how UDOT evaluated each potential transportation solution and made decisions about which would be carried forward into the Draft Environmental Impact Statement for further study and which would be eliminated.


Detailed Response

  • The alternatives development and screening process described in the Alternatives Development and Screening Report provides critical information about how well an alternative or concept satisfies the project’s purpose. This process also assists with determining whether an alternative meets the regulatory standards under a variety of federal statutes, such as the National Environmental Policy Act (NEPA), the Clean Water Act, Section 4(f) of the Department of Transportation Act of 1966, and Section 6(f) of the Land and Water Conservation Fund Act of 1965.

I-15 Questions

Primary Response

  • While the growing population of Utah and the aging pavement and bridges along I-15 in the study area require that we look at ways to improve mobility along the freeway itself, including adding capacity to meet the growing demand, we have put significant focus on a holistic approach to transportation within this corridor. That includes how best to get people where they’re going safely and easily, whether it be in a vehicle, on a bus or train, or on a bicycle or by foot. Widening I-15 is part of a comprehensive approach to meeting transportation demand through the year 2050 that includes added capacity to FrontRunner, additional bus service, local and regional roadway improvements and new facilities for those who walk and bike.


Detailed Response

  • Our analysis of travel demand assumes that all projects in the current Regional Transportation Plan – including roadway, transit and bike/pedestrian trails – are successfully implemented in addition to any improvements to I-15.
  • After all those other improvements were assumed, it was clear additional freeway capacity was needed. Our team assessed how many lanes it would take to not just improve conditions today, but to improve conditions in 2050. We looked at several different widening options, alongside what would happen if we added no capacity to I-15. The widening options included the following:
    • Widening to 3-4 general purpose lanes + 3 High Occupancy Toll (HOT) lanes
    • Widening to 5 general purpose lanes + 2 reversible lanes (presented during the Alternatives Phase Comment Period)
    • Widening to 5 general purpose lanes + 1 HOT lane (presented during the Alternatives Phase Comment Period)
    • Widening to 5 general purpose lanes + 2 HOT lanes
    • Widening to 6 general purpose lanes + 1 HOT lane
  • Only the 5 general purpose + 1 HOT lane option and the 5 general purpose lanes + 2 reversible lanes option were presented during the Alternatives Phase because these provided benefit in 2050 with less impact as compared to the other, wider options. At Level 2 screening, it was determined that the 5 general purpose lanes + 1 HOT lane concept would provide benefit while minimizing impact the most.
  • If no capacity is added to I-15, even with all the other transportation improvements successfully implemented, we project it would take more than an hour to travel through the study area. By comparison, by implementing the 5 general purpose + 1 HOT lane option, we project a travel time of 30 minutes. While this is still an increase in travel time over today, we feel this best balances travel improvement with impact to the surrounding community.

Primary Response

  • As Utah grows, people will need many options to get around, including by vehicle, transit, bicycle and walking. To accommodate the population growth we expect by 2050, we will need to expand all travel options. Our models account for projected growth, including demand from more people and the additional trips that may be taken by car because there is capacity. We have planned to accommodate some – but not all – of the expected growth in demand for travel on I-15. To fully meet the expected demand for freeway travel it would require more lanes than UDOT understands the community would like to see.


Detailed Response

  • Utah, the Wasatch Front and Intermountain West (Idaho, Montana, Colorado, and Nevada) are growing and are projected to continue to grow between now and 2050. The population of Utah in 1960 when this segment of I-15 was initially constructed was less than 900,000. In 2022 Utah’s population was approximately 3.3 million. The population in Utah is projected to be 5.0 million in 2050, with around 3.6 million people just in the Wasatch Front counties (Salt Lake, Davis, Weber, and Utah Counties).
  • We consider both current and future demand in our transportation planning process. We need to accommodate our fastest-in-the-nation population growth, while keeping our system running smoothly and supporting the long-term plans of our cities, counties and metropolitan areas.
  • We know that preparing for the future requires many transportation options, so we work closely with our partners – like UTA, local governments, regional planning agencies – to create more choices so people can get where they want in the way they want.
  • We focus on identifying feasible improvements that provide the most value, because we’re committed to being good stewards of taxpayer funds and getting the most out of finite resources.
  • It’s also important to note that I-15 is a regional facility serving national, regional, and local traffic. The interstate system fills an important role in the western U.S., not just Utah. In addition to moving people, it is estimated that the nation’s roadway system carries 71% of the freight we use as a society.
  • UDOT uses the regional travel demand model that is jointly maintained by the Wasatch Front Regional Council (WFRC) and Mountainland Association of Government (MAG) to forecast future travel demand. This model has been reviewed by the Federal Highway Administration and Federal Transit Administration for use in transportation planning and is the best available model for this purpose. The travel demand model uses existing travel data and then predicts future travel demand based on projections for land use (from city, county, and region master plans), socioeconomic patterns such as population and employment growth, and the planned transportation networks (for all modes).

Transit/Travel Behavior Questions

Primary Response

  • Traffic analysis shows that to meet the travel needs of all the people we expect to be in this area of Utah by 2050, all travel modes – roadways, transit, bike and pedestrian paths – will need to be expanded. Either transit or road expansion alone will not meet the need. Our study assumes that all other planned projects – roadway, transit and bike/pedestrian – are constructed when we evaluate what travel in the study area would look like without improvements to I-15. We then assess how improvements to I-15 and its adjacent roadways can help meet the transportation needs, not only for vehicles but also to better connect people to transit and bike and pedestrian opportunities.


Detailed Response.

  • There are currently funds programmed for both the FrontRunner Double Track (called FrontRunner Forward by UTA) and a potential I-15 project.
  • Double tracking FrontRunner is a planned project on the 2050 RTP and is part of the I-15 EIS’s no-action scenario, which assumes all other roadway, transit, and active transportation projects in the 2050 RTP are constructed except the I-15 EIS project. The FrontRunner Double Track is currently in the environmental review and design process. The timing of construction has not been determined yet, but it is anticipated to begin construction shortly after the completion of the environmental and design process.
  • UDOT is actively coordinating with UTA on the FrontRunner Forward/double track project. The I-15 alternative designs preserve space needed for UTA to construct the double track in areas where FrontRunner and I-15 are adjacent to one another (primarily in West Bountiful, Centerville and Farmington). UDOT, UTA, Woods Cross and Farmington are coordinating on ways to improve pedestrian, cyclist, and roadway connections to the Woods Cross and Farmington FrontRunner stations with the I-15 EIS project.

Primary Response

  • Our study assumes all other projects – roadway, transit, bike and pedestrian – are completed and successful before assessing potential improvements to I-15. Even with all those other projects in place, I-15 remains a critical piece of mobility solutions now and in the coming decades. Further, the aging infrastructure of I-15 must be rebuilt for maintenance and safety reasons.


Detailed Response

  • The 2050 RTP includes all transit projects identified by the Utah Transit Authority (UTA). The I-15 EIS’s no-action scenario assumes all other roadway, transit, and active transportation projects in the 2050 RTP are constructed except the I-15 EIS project. I-15 is one component of the region-wide transportation system. The WFRC 2050 RTP shows that additional capacity is needed on both I-15 and FrontRunner (as well as many other roadway and transit projects) to meet 2050 travel demand.
  • A transit only alternative does not meet the project purpose. As stated in the project’s purpose and needs, in addition to mobility/capacity needs, the I-15 needs also include addressing aging infrastructure, improving access and providing safer pedestrian and bicyclist facilities.

Primary Response

  • The traffic model we used to assess the needs along and around I-15 does account for expected changes in travel behavior between now and 2050. Even accounting for those changes and accounting for shifts to other modes of travel as those modes are improved and expanded, improvements to I-15 are still needed.


Detailed Response

  • UDOT does not have jurisdiction on whether to allow or not allow development. The local cities and private property owners make decisions on local land use and development.

Impact Questions

Primary Response

  • Detailed engineering and analysis are still taking place, so specific impacts to properties will not be known until later in the process. If you have already heard from someone about assessing or compensating you for impacts – such as someone trying to purchase your home – please know UDOT has not initiated any such actions, and we’d encourage you to contact our team for the latest information before pursuing that kind of conversation.


Detailed Response

  • In some cases, the necessary improvements will result in impacts to a portion or all of a property. In those cases, UDOT must follow federal and state ROW procedures and processes (Acquisition Services | UDOT (utah.gov)).

Primary Response

  • While we are still assessing potential impacts to adjacent properties, some impact information is available in the Alternatives Development and Screening Report. After more detailed engineering and analysis, we expect to release more detailed information about potential impacts in the Draft Environmental Impact Statement (DEIS) later this fall.


Detailed Response

  • When we shared the proposed alternatives, we only knew an alternative or option could meet the purpose and need. We are now in the process of refining the alternatives through detailed engineering work. This includes working to minimize impacts to surrounding properties as much as possible.
    • In some areas, like Salt Lake City for example, there is some space between the northbound and southbound lanes of I-15 to add capacity toward the center, reducing needed width toward the outside of the current freeway footprint.
    • In other areas there is more available space on one side of the freeway or cross-street, and where that is the case, we are doing our best to use that available space before impacting homes or businesses.
    • In some cases, the necessary improvements will likely result in impacts to a portion or all of a property. In those cases, UDOT must follow federal and state ROW procedures and processes (Acquisition Services | UDOT (utah.gov)).
  • Detailed assessment of property impacts will be provided as part of the DEIS after engineering design is more advanced and more detailed information about property impacts can be determined.

Primary Response

  • Generally, emissions from cars and trucks that contribute to our air quality challenges will continue to decrease even as we grow, thanks primarily to improvements in vehicle technology. Our study will assess the effect of any proposed project on the overall air quality in the region as part of the Regional Transportation Planning process.


Detailed Response

  • Transportation is one source/sector that contributes to air quality issues in the Salt Lake Valley and includes vehicle emissions from personal vehicles, FrontRunner, buses, airplanes, and motorcycles. Other primary sources include industrial and commercial point sources, and area sources, which include emissions from residential and commercial development (furnaces, dry cleaners, restaurants, lawn mowers, etc.).
  • Air quality impacts from the project (localized air quality analysis) will be analyzed in the EIS and follow FHWA and UDOT policies and procedures using approved air quality models. Generally, localized air quality is better with free-flowing traffic than with congested conditions due to there being less concentrated vehicle emissions over time in the same location.
  • We are also aware of a study being conducted by the US Environmental Protection Agency (EPA) on air quality on the west side of Salt Lake City. We have connected with those leading the study and will use any learnings from that effort in our planning.
  • The number of lanes on I-15 proposed with the I-15 EIS alternatives is consistent with the assumptions in the WFRC 2050 RTP. The WFRC 2050 RTP conducts a regional air quality conformity analysis, which takes into account all existing and planned 2050 major transportation facilities (Microsoft Word – AQ memo39_RTP_2019-2050_FINAL.docx (wfrc.org)).

Primary Response

  • Noise is an impact assessed as part of the Draft Environmental Impact Statement (DEIS). More information on noise will be available when that is released in fall of 2023.


Detailed Response

  • Noise impacts and mitigation will be addressed in the DEIS for alternatives advanced through screening. The assessment of noise impacts and mitigation will follow the UDOT Noise Abatement Policy and procedures (Noise Walls | UDOT (utah.gov)).

Primary Response

  • We understand that alternatives we are studying have potential to cause impacts to historically underserved populations. Further, we know I-15 is a barrier within communities. With this study we are looking at ways to provide better connections across I-15 via vehicle, bicycle or walking and to better connect to transit options to improve conditions while also minimizing any impacts to specific communities as much as possible.


Detailed Response

  • UDOT is aware of EJ communities and will try to minimize impacts from the project and provide new amenities/improvements to help mitigate current and past impacts related to I-15. A more detailed Environmental Justice (EJ) analysis will be provided as part of the DEIS and will follow all current federal rules, regulations, and guidance for both public involvement and impacts assessment.

Primary Response

  • UDOT acknowledges impacts of past decision-making on the west side of Salt Lake City. With this study, we are seeking ways to not only minimize further transportation impacts to these communities, but also to provide better connections across I-15 via vehicles, bicycle or walking and to better connect to transit options, to enhance mobility for all people in this portion of the study area.


Detailed Response

  • UDOT is aware of past actions and impacts, particularly in Salt Lake City (from I-15 and other actions unrelated to UDOT). UDOT will attempt to minimize impacts to the adjacent neighborhoods as much as possible during design while meeting the needs for the project. Consistent with its Quality of Life Framework and the purpose and need for the project, UDOT is proposing new connections (e.g., 400 N.) and safer, more community friendly access points and crossings (e.g., 600 N.) and an upgraded Warm Springs interchange to try to take some truck traffic out of residential areas around 600 N. to help reduce the east-west divide and improve community connections.
  • Proposed transportation improvements are meant to benefit all transportation users in the area, including those who use I-15, 600 North and 1000 North. A functional/less congested I-15 and I-15/600 North interchange that improves mobility is also a benefit to adjacent EJ neighborhoods who use I-15 to access their neighborhoods.
  • A more detailed Environmental Justice (EJ) analysis will be provided as part of the Draft Environmental Impact Statement (DEIS) and will follow all current federal rules, regulations, and guidance for both public involvement and impacts assessment. This will include any EJ communities on the west side of Salt Lake City. UDOT will also coordinate with EPA and Salt Lake City on the EPA study planned for the west side of Salt Lake.

Questions by Specific Geography

  • Options Moving Forward:
    • Based on the Level 2 screening analysis and comments from the public and agencies received during the draft alternatives public comment period, UDOT advanced Salt Lake Option A for detailed evaluation in the Draft EIS.
      • The advanced Salt Lake Option A includes two 1000 North options, the Salt Lake City 1000 North – Northern Option and the Salt Lake City 1000 North – Southern Option.
  • Key features of Salt Lake Option A include:
    • 400 North: new underpass of I-15 with sidewalks and roadway crossing.
    • Diamond interchange at 600 North with collector-distributor ramps to 1000 North.
      • Buffered or barrier-separated bike lanes and 8‑foot-wide sidewalks on both sides of 600 North.
      • No free right-hand turns and better sight lines for vehicles at the 600 North interchange, thereby enhancing safety for bicyclists and pedestrians.
    • Full access (northbound on and off, southbound on and off) to I-15 will be provided with this collector-distributor system at 1000 North (for both of the 1000 North options).
      • 12‑foot-wide shared-use path on 1000 North that crosses under I‑15 and connects to Warm Springs Road east of I‑15.
    • Full access diamond interchange at 2100 North/Warm Springs; this interchange includes a new road connection to U.S. 89/Beck Street with a grade-separated overpass of the railroad tracks to reduce truck traffic on 600 North and 300 West in the Marmalade neighborhood.
    • New U.S. 89 12‑foot-wide shared-use path between Eagle Ridge Drive in North Salt Lake and Wall Street/200 West in Salt Lake City.
  • Eliminated Options:
    • Because the 600 North SPUI and 1800 North interchange would not meet the Level 1 screening criteria of better connecting communities and supporting bicyclists and pedestrians, UDOT eliminated this alternative during Level 1 screening.
    • During Level 2 screening, UDOT eliminated all four tunnel options to bury I‑15 in Salt Lake City and the roundabout option at 600 North 800 West. See response below for more information on the four tunnel options.
  • See Section 3.2.3, Level 2 Screening for Interchange and Bicycle and Pedestrian Concepts in Salt Lake, of the Alternatives Screening Report for more information.

Primary Response

  • We have looked at several different options for reconstructing I-15 underground in the Salt Lake City area. Because all of these options increase impacts to the surrounding communities significantly, and due to many technical challenges – such as hydraulic, geotechnical, roadway configurations and utility impacts – we have screened out putting I-15 underground. Other options to better connect the community in this area are included in the detailed analysis of the Draft Environmental Impact Study (DEIS).


Detailed Response

  • Based on comments and requests received during the draft alternatives public comment period, UDOT also evaluated burying I‑15 in Salt Lake City between North Temple and 600 North. Four different versions of a buried tunnel option for I‑15 in Salt Lake City were evaluated
  • Compared to Salt Lake Option A, any of the four tunnel options would have substantially more impacts to the adjacent residential properties, churches, commercial properties, and historic properties in just the section of I‑15 between North Temple and the 600 North interchange area. For just one data point, the tunnel options would require relocation of 180 to 1,270 more residential households more than the 24 potential residential relocations estimated for Salt Lake Option A. All of these impacted properties are located in areas that are identified as having lower-income and/or minority populations and several of the apartment buildings are low-income housing apartments. All four tunnel options were screened out due to the substantially higher impacts to the community compared to Salt Lake Option A.
  • See Section 3.2.3, Level 2 Screening for Interchange and Bicycle and Pedestrian Concepts in Salt Lake, and Appendix B, Salt Lake City Tunnel Options, of the Alternatives Screening Report for more information.
  • Option Moving Forward:
    • Based on the Level 2 screening analysis and comments from the public and agencies received during the draft alternatives public comment period, UDOT advanced North Salt Lake/Woods Cross Option B for detailed evaluation in the Draft EIS.
  • Key features of North Salt Lake/Woods Cross Option B include:
    • New U.S. 89 12‑foot-wide shared-use path between Eagle Ridge Drive in North Salt Lake and Wall Street/200 West in Salt Lake City.
    • New I-15/I-215/U.S. 89 local interchange in North Salt Lake.
    • Center Street buffered or barrier-separated bike lanes on both sides, 6‑foot-wide sidewalk on north side, and 12‑foot-wide shared-use path improvements on south side of Center Street between I‑15 and 400 West.
    • Wider bridge over Main Street to accommodate future bicyclist and pedestrian improvements.
    • 2600 South SPUI interchange
      • At 2600 South, no free right-hand turns for vehicles and better sight lines, thereby enhancing safety for bicyclists and pedestrians.
      • Buffered or barrier-separated bike lanes on both sides of 2600 South.
      • 8‑foot-wide sidewalk on the north side of 2600 South.
      • 14‑foot-wide grade-separated shared-use path on south side of 2600 South.
    • 800 West (Woods Cross): new underpass of I‑15 with new 12‑foot-wide shared-use path. 12‑foot-wide shared-use path connection between 800 West and 2600 South on west side of I‑15.
    • Wider bridge over 1500 South to accommodate future bicyclist and pedestrian improvements.
  • Eliminated Options:
    • UDOT eliminated North Salt Lake/Woods Cross Option A because it would duplicate Option B and would result in similar impacts as Option B. Although both Options A and B can suitably accommodate the projected traffic volumes at the 2600 South interchange, Option B has more capacity and is able to move the projected traffic more efficiently. The quarter interchange at Center Street (with the southbound off‑ramp) was eliminated during Level 1 screening. The City of North Salt Lake has a desire for Center Street to cross over or under the UTA FrontRunner and Union Pacific railroad tracks at 300 West. The I‑15 project would be forward-compatible with either option. Removing the Center Street southbound off‑ramp would improve operations on I‑15 by reducing the number of off‑ramps in North Salt Lake between the 2600 South on-ramp and the I‑215 off-ramp. See Section 3.2.3, Level 2 Screening for Interchange and Bicycle and Pedestrian Concepts in North Salt Lake/Woods Cross, of the Alternatives Screening Report for more information.
  • Option Moving Forward:
    • Based on the Level 2 screening analysis and comments from the public and agencies received during the draft alternatives public comment period, UDOT advanced Bountiful/West Bountiful Option A for detailed evaluation in the Draft EIS. Option A would be the most consistent with current traffic patterns and would maintain all existing business accesses. Option A would also have the fewest impacts to the business and commercial properties between 400 North and 500 West on the east side of I‑15.
      • The advanced Bountiful/West Bountiful Option A includes two 500 South options, the Bountiful 500 South – Northern Option and the Bountiful 500 South – Southern Option; and two 400 North options, the Bountiful 400 North – Northern Option and the Bountiful 400 North – Southern Option.
  • Key features of Bountiful/West Bountiful Option A include:
    • Diamond interchange at 500 South in Woods Cross/Bountiful/West Bountiful.
      • 12‑foot-wide shared-use path on both sides of 500 South (Figure 4‑13).
      • No free right-hand turns for vehicles and better sight lines, thereby enhancing safety for bicyclists and pedestrians.
    • New shared-use path connection from 500 South to Woods Cross FrontRunner Station west of I‑15.
    • Half diamond/split diamond interchange at 400 North/500 West in Bountiful/West Bountiful
      • Northbound off-ramp and southbound on-ramp at 400 North
      • Northbound on-ramp and southbound off-ramp (from right side of I-15) at 500 West
      • Buffered or barrier-separated bike lanes on both sides of 400 North
      • 12‑foot-wide shared-use path on the north side of 400 North
      • 6-foot-wide sidewalk on the south side of 400 North
    • Wider bridge over 1600 North/Pages Lane to accommodate future bicyclist and pedestrian improvements.
  • Eliminated Options:
    • UDOT eliminated Bountiful/West Bountiful Options B and C during Level 2 screening. UDOT eliminated Bountiful/West Bountiful Options B and C because they would duplicate Option A and would result in similar, but slightly higher, impacts compared to Bountiful/West Bountiful Option A.
  • See Section 3.2.3, Level 2 Screening for Interchange and Bicycle and Pedestrian Concepts in Bountiful/West Bountiful, of the Alternatives Screening Report for more information.
  • Option Moving Forward:
    • Based on the Level 2 screening analysis and comments from the public and agencies received during the draft alternatives public comment period, UDOT advanced Centerville Option B for detailed evaluation in the Draft EIS. Because Option A would have slightly higher impacts and because Option B would provide more traffic benefits, UDOT advanced Centerville Option B through Level 2 screening.
  • Key features of Centerville Option B include:
    • Parrish Lane SPUI interchange
      • At Parrish Lane, no free right-hand turns for vehicles and better sight lines, thereby enhancing safety for bicyclists and pedestrians.
      • 14‑foot-wide shared-use path on the north side of Parrish Lane.
    • Grade-separated 14‑foot-wide shared-use path crossing of I‑15 and railroad tracks at 200 North (south of Parrish Lane).
    • New grade-separated 14‑foot-wide shared-use path crossing at Centerville Park over I‑15/railroad tracks/Legacy Parkway.
  • Eliminated Options:
    • UDOT eliminated Centerville Option A because it would duplicate Option B and would result in similar, but slightly higher, impacts as Option B. Although both Options A and B can suitably accommodate the projected traffic volumes at the Parrish Lane interchange, Option B has more capacity and is able to move the projected traffic more efficiently. UDOT eliminated Centerville Option A because it would duplicate Option B and would result in impacts slightly higher than those of Option B.
  • See Section 3.2.3, Level 2 Screening for Interchange and Bicycle and Pedestrian Concepts in Centerville, of the Alternatives Screening Report for more information.
  • Options Moving Forward:
    • Based on the Level 2 screening analysis and comments from the public and agencies received during the draft alternatives public comment period, UDOT advanced Farmington Option A for detailed evaluation in the Draft EIS. Because Farmington Option A would be the most consistent with the current access and would have the fewest impacts, it was advanced to Level 2 screening.
      • The advanced Farmington Option A includes two options by State Street; the Farmington 400 West Option and the Farmington State Street Option.
  • Key features of Farmington Option A include:
    • Updated half interchange at 200 West in Farmington.
      • Maintains the existing northbound off-ramp and southbound on-ramp at 200 West
      • New design has a new interchange for 200 West and the frontage road that provides improved access to both northbound and southbound frontage road from 200 West and maintains a free-flow movement to the northbound frontage road from the 200 West off-ramp
      • No free right-hand turns for vehicles and better sight lines, thereby enhancing safety for bicyclists and pedestrians
    • Glovers Lane bridge over I‑15 and the railroad tracks is widened to include a 10‑foot-wide sidewalk on the north side, a 6‑foot-wide sidewalk on the south side and buffered or barrier-separated bike lanes on both sides to match the facilities going over Legacy Parkway.
    • State Street/Clark Lane bridge over I‑15 and the railroad tracks is widened to include buffered or barrier-separated bike lanes and sidewalks on both sides that match the facilities going over Legacy Parkway.
  • Eliminated Options:
    • UDOT eliminated Farmington Option B (Glovers Lane SPUI) in Level 2 screening due to the substantially higher impacts to residential properties and the change in traffic patterns that would result in higher traffic volumes on residential roads that have not been planned to accommodate traffic accessing an I‑15 interchange.
    • Farmington Option C (200 West full interchange) would potentially require relocation of three more residential properties on the east side of I‑15 near 200 West due to a wider footprint on the east side of I‑15 to accommodate the new full-access interchange and local road connections with Option C. UDOT eliminated Farmington Option C because it would substantially duplicate Farmington Option A and would result in substantially similar, but slightly higher, impacts compared to Farmington Option A.
  • See Section 3.2.3, Level 2 Screening for Interchange and Bicycle and Pedestrian Concepts in Farmington, of the Alternatives Screening Report for more information.

Primary Response

  • The Rio Grande plan is not an adopted part of the Regional Transportation Plan or part of a locally adopted transportation plan. Further, it does not address the needed upgrades to aging infrastructure on I-15, nor does it directly improve transportation options between Salt Lake City and Farmington as identified in our study’s purpose and need.


Detailed Response

  • The Rio Grande Plan does not address the I-15 project’s purpose and need. Aging infrastructure on I-15 is one element of the purpose and need that needs to be satisfied by an alternative. The Rio Grande Plan would not address the maintenance, safety, economic, or mobility needs for I-15. The I-15 project is still needed whether the Rio Grande Plan is implemented or not.

Draft Alternatives Design

The below image links to the current DRAFT design for remaining I-15 alternatives. Please remember that design is still being refined, and that this map shows the draft alternatives as of May 2023. Any updates to the draft alternatives and more detailed information about impacts will be available at the time of the Draft EIS, which is currently anticipated in fall 2023. Once on the map, please use the drop down menu on the upper right hand side of the map to select and unselect design options to view throughout the study area.

DRAFT I-15 EIS Alternatives Design

Environmental Study Timeline

Environmental Study Process

The study team is following the EIS process established by the National Environmental Policy Act (NEPA). This includes:

  • Learning about issues, needs and potential solutions from the public and other stakeholders.
  • Establishing a purpose and need for any proposed improvements.
  • Developing a broad range of potential transportation solutions.
  • Evaluating environmental impacts of those proposed solutions.
  • Selecting an alternative that best meets the needs.
  • Continuous public and stakeholder engagement.

NEPA Process Video (English)

NEPA Process Video (Español)

Quality of Life Framework

As the population in Utah continues to grow at a record pace, transportation planning and development play a key role in keeping Utah moving, facilitating a strong economy, and maintaining a high quality of life. As such this study will use the Quality of Life Framework outlined below to inform decision making including in developing the study Purpose and Need.

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