About
The Utah Division of Transportation (UDOT) has recently initiated the public outreach phase of their environmental study of the I-15 corridor between Farmington and Salt Lake City. UDOT launched the overall environmental study to propose solutions for projected transportation needs in surrounding communities.
Proposed I-15 expansion

- Option A would include six lanes in each direction, including an auxiliary lane on the sides, plus a single high-occupancy vehicle (HOV) lane in the middle. This proposal would bring the corridor to 18 lanes, including emergency lanes.
Option B would have 20 lanes across, including a reversible HOV lane open to southbound motorists in the morning and northbound at night. Barriers would protect option B’s addition of a reversible HOV lane.
How will this impact our environment and 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). This is due to weather-related events, topography, and emissions.
Countless studies have shown evidence 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 and air pollution.
- UDOT has yet to disclose how many homes and businesses will be affected by the expansion. We encourage UDOT to first study and publish a report of displacement from expansion before moving forward with any proposal.
- Investment in Public Transit will prioritize getting people off the road and lead to a decrease in vehicle-source emissions. We know from past studies and free fare programs that investing in public transit leads to increased ridership and better air quality days.
- HEAL advocates for expanded access to and use of a fair public transportation system to combat the climate crisis, address the air quality issues that negatively affect public health, and benefit both users and communities. To achieve these goals, transportation planning must be based on the needs and voices of those who use it most often, as we seek to address disparities in mobility and access.
- Prioritize maintenance of existing infrastructure and safety measures for walking and biking, especially in communities close to high-speed roads or without sidewalks.
Better ways to keep Utah moving and include community input
- 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, has disproportionately been exposed to higher levels of environmental impacts. Recent studies indicate a higher concentration of air pollution in West Side communities and a higher concentration of urban heat islands in surrounding communities
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 on passenger vehicles.
Take Action- CLOSED
Thank you to everyone who submitted public comments. Our team will continue to watch this issue and alert you on any upcoming opportunities to engage.
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Climate Change and Air Quality (Vehicle Source Emissions)
- Air Pollution: Know Your Enemy
- Nearly 9 out of 10 Salt Lakers Drives to Work Alone
- Monitoring of greenhouse gases and pollutants across an urban area using a light-rail public transit platform
- Driving Down Emissions: The urgency of the climate crisis demands it
Costs
- Paying for Poor Air: The Cost of Regional Air Pollution
- The staggering economic cost of air pollution
- Air pollution emissions and damages from energy production in the U.S.: 2002–2011
- BYU: Air pollution costs Utahns billions annually and shortens life expectancy by two years
- Highway Boondoggles
- Innovative Ways to Deal with Traffic Congestion & Road Funding
- CO2 AND CARBON EMISSIONS FROM CITIES: Linkages to Air Quality, Socioeconomic Activity, and Stakeholders in the Salt Lake City Urban Area
- No More Freeways: Urban Land Use-Transportation Dynamics without Freeway Capacity Expansion
Public Health
- How Mobile Source Pollution Affects Your Health
- BYU: Air pollution costs Utahns billions annually and shortens life expectancy by two year
- HumanHealth and Economic Costs of Air Pollution in Utah: An Expert Assessment
- Living Near Highways and Air Pollution
Environmental Justice/Community Impacts