Is I-15 in St. George Under Construction? Quick Answer
Not yet, but soon. The Utah Department of Transportation (UDOT) says construction to widen I-15 between Bluff Street (Exit 6) and St. George Boulevard (Exit 8) is expected to begin in November 2026. As of Nov. 8, the project's "Impacts and Updates" page says no traffic impacts are scheduled.
Bluff Street (SR-18) is already a work zone. UDOT's Bluff Street project page says construction is ongoing, the speed limit through the zone is now 35 mph and traffic fines are doubled.
| I-15 widening | Bluff Street (SR-18) | |
|---|---|---|
| Where | I-15, Bluff Street (Exit 6) to St. George Boulevard (Exit 8) | Bluff Street, described by UDOT as St. George Boulevard to Main Street |
| Status (Nov. 8) | Construction expected to begin November 2026; no traffic impacts scheduled yet | Under construction |
| Cost (UDOT, March 26) | $175 million | $38.3 million |
| Finish | Spring 2029 (project page) / winter 2028 (March release) | Winter 2028 (March release) |
| Hotline | (435) 280-2266 | 435-531-1358 |
UDOT has published two different schedules for the I-15 work. Its project page says construction runs fall 2026 through spring 2029. Its March 26, 2026, statewide construction release said work would begin in the summer and end in winter 2028. We list both because UDOT has not reconciled them.
What Will the I-15 Project Change?
According to UDOT's project page, crews will:
- Widen I-15 from two lanes to three in each direction between Exit 6 and Exit 8. The new lanes go on the inside, toward the median, to avoid substantial property impacts.
- Replace and raise the I-15 bridges at 100 South and 700 South to fit the added lanes and meet minimum clearance height.
- Build new bridges over 400 East and 900 South so those streets can pass under I-15 and connect the two sides of town.
- Improve drainage along I-15 and local cross streets to reduce flooding.
- Build two noise walls on the east side of I-15.
- Realign existing utilities and install new ones.
Two things the project won't do: UDOT says it won't build the single-point urban interchange at 700 South that its 2022–2023 environmental assessment recommended. That waits for a later phase "due to fiscal constraints."
Is it funded? Yes. In its FAQ, UDOT says the project "is not cancelled. It is funded and will be constructed." State transportation funds cover the widening and the noise walls. The raised interstate and the new 400 East and 900 South bridges are funded by UDOT, the City of St. George and a $23.5 million federal BUILD grant from the U.S. Department of Transportation.
What Is Happening on Bluff Street Right Now?
UDOT's latest Bluff Street update lists this work along the corridor:
- New sidewalk along the west side of the project, scheduled Nov. 2–10, plus sidewalk and pedestrian accessibility work between 900 South and Main Street.
- Asphalt paving throughout the corridor, with access to nearby properties maintained. UDOT says paving is underway just south of Spilsbury Mortuary.
- 800 South night closures: sewer installation at 800 South is complete, but crews will temporarily close 800 South at night to install a sewer manhole.
- Utility work on a water loop and sewer conflicts near Spilsbury Mortuary, and gas and electrical work between 700 South and 900 South.
- A new traffic signal at 900 South.
- Curb, gutter, driveway approaches, and gutter along the top of the soil nail wall.
UDOT also says 950 South is now open.
The finished project, per UDOT, will increase intersection capacity, improve stormwater collection, resurface the road, add landscaping and add raised medians to cut down on conflict points. Raised medians mean some left turns into businesses will change, so watch the signs and allow extra time.
When Do Crews Work on Bluff Street?
Monday through Friday. UDOT says two crews may work at once: days from 7 a.m. to 7 p.m. and nights from 9 p.m. to 6 a.m. Schedules can change with weather and material availability. UDOT asks drivers to allow extra travel time, watch for crews and equipment, and keep shopping at the businesses along the corridor.
How Do I Get Construction Updates?
- I-15: (435) 280-2266 or i15stgeorge@utah.gov. The project page has a sign-up form for updates.
- Bluff Street: 435-531-1358 or stgeorgedowntown@utah.gov. To get updates, email with "Project Updates" in the subject line.
UDOT also posts live traffic data on its UDOT Traffic website.
More road and growth news from St. George: the city council's Nov. 5 agenda included a $440,778 oversight contract for the SR-7 Exit 5 interchange, and heading to Zion, UDOT has nightly Zion tunnel closures Nov. 16–20. Planning a holiday trip into town? See things to do in St. George this November.
Frequently Asked Questions
When does the I-15 widening in St. George start?
UDOT's project page says construction is expected to begin in November 2026. As of Nov. 8 it lists no scheduled traffic impacts. UDOT has published two end dates: spring 2029 on the project page and winter 2028 in its March 26 release.
Which part of I-15 is being widened?
I-15 between Bluff Street (Exit 6) and St. George Boulevard (Exit 8). UDOT will add a third lane in each direction, widening toward the median to limit property impacts.
Is UDOT building an interchange at 700 South?
Not in this project. UDOT says it will not build the single-point urban interchange recommended for 700 South in the 2023 environmental study because of fiscal constraints. It will replace and raise the I-15 bridges at 100 South and 700 South.
What is the speed limit in the Bluff Street construction zone?
35 mph. UDOT's Bluff Street project page says traffic fines are doubled in the work zone.
What hours do Bluff Street crews work?
Monday through Friday. Day crews work 7 a.m. to 7 p.m. and night crews 9 p.m. to 6 a.m. UDOT says schedules can change with weather and material availability.
Who do I call about I-15 or Bluff Street construction?
The I-15 project hotline is (435) 280-2266 or i15stgeorge@utah.gov. The Bluff Street hotline is 435-531-1358 or stgeorgedowntown@utah.gov.
Sources: UDOT, "I-15 | St. George Boulevard to Bluff Street" project page (overview, Impacts and Updates, FAQ and timeline, accessed Nov. 8, 2026); UDOT, "Bluff Street | St. George Blvd to Main Street" project page (Impacts & Updates and schedule, accessed Nov. 8, 2026); UDOT, "UDOT announces $2.8 billion in new and ongoing 2026 construction," March 26, 2026.
