Big Cottonwood Canyon averaged 15,300 vehicles on Saturdays in recent weeks, nearly double the 8,900 Saturday average recorded in May.

The Utah Department of Transportation (UDOT) reviewed traffic sensor data at the mouths of Big Cottonwood Canyon, Little Cottonwood Canyon and the Alpine Loop, as ABC4 first reported Friday, Oct. 9. Big Cottonwood Canyon topped all three routes.

Weekday counts jumped, too. The canyon averaged 9,300 vehicles per weekday in the fall weeks leading up to Oct. 9, up from 4,700 in May. During peak hours, more than 1,200 vehicles passed through the canyon mouth in a single hour.

For Millcreek residents who use Big Cottonwood Canyon for hiking, biking and fall color drives, the numbers translate to longer waits at the canyon entrance on weekends.

Little Cottonwood Canyon and the Alpine Loop saw similar surges. Peak days across all three routes topped 15,000 vehicles, according to ABC4's report.

A Sept. 9 Salt Lake Tribune report forecast Salt Lake County's peak fall foliage between Sept. 30 and Oct. 6, though the prediction carried a margin of up to 15 days. OpenSnow forecaster Evan Thayer told the Tribune at the time that "the Cottonwood Canyons are always a safe bet for seeing the leaves change." UDOT collected its traffic data in the weeks following that forecast.

The Utah County Sheriff's Office advised Alpine Loop visitors to expect the heaviest congestion between noon and 6 p.m. and to park with all wheels off the pavement on the narrow, centerline-free road.

UDOT finalized a long-term transportation plan for Big Cottonwood Canyon in May 2026 that includes expanded bus service and congestion-based tolling, projected to begin in November 2028, according to the conservation group Save Our Canyons. The plan also calls for a 1,750-stall mobility hub near the base of the canyon.

Until that infrastructure arrives, Millcreek canyon-goers heading up Big Cottonwood on a Saturday should plan for 15,000-plus vehicles sharing the road.

Upcoming

  • Nov. 7, 2026: Salt Lake County general election, including the $128M parks bond that would fund trail and open-space improvements
  • November 2028 (projected): UDOT enhanced bus service and congestion tolling begin in Big Cottonwood Canyon