UDOT outlines timeline and traffic findings for SR‑189/US‑40 bypass study

Craig Hancock of UDOT Region 3 told the Wasatch County Council on Dec. 11 that the agency remains on schedule for the SR‑189/US‑40 bypass study, with an alternatives screening report planned for early spring 2025, a draft Environmental Impact Statement in fall 2025 and a Record of Decision targeted for spring 2026.

Hancock said the study has refined alternatives into two main families: at‑grade options that add lanes on the North 40 alignment and free‑flow options that use interchanges and direct‑connect ramps so drivers can traverse the bypass without stopping. "Our goal is to, complete the screening process and have a report out for the community to to see that, early spring of 20 25," Hancock said.

UDOT presented PM peak travel‑time modeling on representative paths. On one example path from SR‑32 to US‑189, an at‑grade alignment was modeled at about 10 minutes 20 seconds while another at‑grade alignment took about 8 minutes 20 seconds; free‑flow alternatives reduced the same path to roughly six to seven minutes. Hancock contrasted those results with current conditions on the existing route, which he said can take about 11 minutes 30 seconds in the PM peak.

The presentation also broke down vehicle composition during peak hours: roughly 92% of the traffic stream is private passenger vehicles and about 8% is trucks and other larger vehicles. UDOT told the council that, weighted by vehicle length, trucks occupy a larger share of roadway space. UDOT estimated that about 50% of peak‑hour vehicles on Main Street are local trips, 25% are commuter trips (for example to or from Park City) and 25% are pass‑through traffic. Truck counts vary by hour, with about 20 trucks per hour in the morning and peaks near midday of about 60 trucks per hour.

When asked how counts are made, UDOT said the work uses a combination of physical counts and computer simulations and that modern approaches fuse multiple data sources. Hancock cautioned that the agency prefers to keep the travel‑demand model 'clean' while screening alternatives, and that formally proposed new developments or annexations should be incorporated only after they enter local planning processes.

Councilmembers raised operational concerns, including that the fire district will need reliable north–south access for a planned station near Fitzgerald Lane. Hancock said access needs are on UDOT's radar and that staff will coordinate with the fire district. He also said safety is embedded in UDOT's evaluation even if it is not presented as a separate line item.

The study identified diversion potential onto the bypass ranging by alignment; UDOT showed scenarios where 8–18% of traffic could shift from US‑40 onto the bypass and — depending on the connection to US‑189 — roughly 40% of drivers would take the bypass once they reach that connection.

UDOT said it will continue coordination with Wasatch County, Heber City and stakeholders including NRCS and Utah Open Lands as it finalizes alternatives and prepares the draft EIS.