The Utah Department of Transportation (UDOT) plans to expand I-15 from north Salt Lake to Davis County by adding new lanes in each direction at an estimated cost of $1.6 billion. 


The purpose of the expansion is to repair aging infrastructure and build highway capacity to meet the demands of a growing population. Community members, however, have expressed concerns about the potential negative impacts of the project, including increased noise and air pollution, loss of property and wildlife habitat, disruption to businesses, and the high cost to taxpayers. There are concerns that the expansion may only temporarily reduce traffic congestion and that alternative options like faster and more reliable public transportation, including double-tracking FrontRunner, should be considered instead.

How will this impact our environment and communities?

The environmental and community impacts of expanding  I-15 from Salt Lake City to Farmington include the potential for increased air pollution and greenhouse gas emissions, noise pollution, and destruction of wildlife habitat. Additionally, the expansion may require the acquisition of private property, which could result in the displacement of residents and businesses. And finally, there is no evidence that an expanded freeway is the answer for a growing population.



UDOT’s stated intention is to relieve traffic congestion and repair infrastructure along this route. However, with induced demand, the expansion could result in increased traffic congestion and accidents, negatively affecting the surrounding communities.  

Utah’s most significant contributor to air pollution is vehicle emissions, which cause PM2.5 pollution throughout the Wasatch Front. In Salt Lake Valley alone, residents experience an average of 40 days per year of pollutant levels exceeding the U.S. National Ambient Air Quality Standards (NAAQS) for fine particulate matter. This is due to weather-related events, topography, and emissions. 


Countless studies have shown that the expansion of freeways and highways incentivizes car use and does not result in shorter driving commutes. Instead, the result is an increase in traffic as well as air pollution.

 A typical passenger vehicle emits about 4.6 metric tons of carbon dioxide per year, which exacerbates the human and environmental consequences of global warming. These negative impacts include extreme heat waves and heat islands, drought, and more severe fire seasons in Utah and the West. These environmental and human impacts will only worsen unless we shift away from relying primarily on private passenger vehicles for transport. 


Many people living in areas surrounding the I-15 section, especially west side residents of Salt Lake City, worry about the increased environmental and social economic impacts that communities will face with the proposed expansion. There is a need for more details and data on the potential displacement of surrounding residents and businesses.

Salt Lake City is currently experiencing a crisis in affordable housing. Unfortunately, the situation could worsen due to the proposed expansion of a local freeway. This expansion could displace homes and worsen the existing problem of increased living costs, which is already making it difficult for many residents to make ends meet. It is crucial to note that the expansion project may involve acquiring private property, which could lead to the displacement of residents and businesses. During the construction phase, local businesses may also experience some level of disruption. This displacement of homes and businesses could leave many families without a place to live and add to the already existing problem.

Due to past practices like redlining and discriminatory policies from city and state regulators, the west side of Salt Lake City, which is historically Black, Indigenous, Asian Pacific Islander, and Latinx, is disproportionately exposed to higher levels of environmental hazards. Recent studies indicate a higher concentration of air pollution and urban heat island effects in West Side communities. 

_____ over Freeways coalition

Better ways to keep Utah moving.

If Utah wants to tackle the issue of traffic congestion and population growth, there are better options than expanding freeways. One alternative is to invest in public transportation, such as buses and trains, to provide a more efficient and sustainable way for people to commute between Farmington and Salt Lake City. Investing in safe bike lanes and pedestrian paths provides an alternate mode of transportation for shorter trips. These alternatives are more cost-effective and improve air quality while still keeping people moving.

 It is important to prioritize funding for public transit instead of investing in more roads. However, if we do invest in roads, it should focus on improving pedestrian and bicycle safety and repairing old infrastructure, rather than expanding the road network. Our resources should be spent on finding ways to increase ridership by providing fair access to public transportation. By investing in public transit and maintaining existing infrastructure, we can effectively reduce vehicle emissions and improve air quality throughout the Wasatch Front. To mitigate the increased demand caused by widening I15, double-tracking FrontRunner would be a better solution to spread the demand for transportation.

It is crucial for state agencies like UDOT to work with community members when proposing big projects that could negatively impact residents. This collaboration helps ensure that the community’s concerns and needs are considered and addressed in the project planning and implementation processes. It also helps build trust and transparency between the agency and the community, leading to a more successful and sustainable project outcome. Ultimately, involving community members in the decision-making process can help avoid conflict and ensure that the project benefits everyone involved.

What can you do?

With approval from the State Legislature and under the guidance of the Wasatch Front Regional Council’s Regional Transportation Plan, UDOT allocated 1.6 billion in taxpayer dollars for this highway expansion project. Therefore, you have the opportunity to address your concerns to multiple actors in this process.