Out of the 11 states which I-80 passes through, the segment in Utah is the fourth shortest. As part of the
Interstate Highway System, the entire route is listed on the
National Highway System, a system of roads that are important to the nation's economy, defense, and mobility. Every year, the
Utah Department of Transportation (UDOT) conducts a series of surveys on its highways to measure traffic volumes. This measure is expressed in terms of
annual average daily traffic (AADT), a measure of traffic volume for any average day of the year. In 2012, UDOT calculated that as few as 6,765 vehicles traveled I-80 at the interchange with
SR-58 in Wendover, and as many as 121,205 vehicles used the highway at the
Spaghetti Bowl in
Downtown Salt Lake City. Between 7 and 58 percent of the traffic recorded consisted of trucks. These counts are for the portion of the freeway in Utah.
Tooele County The freeway enters Utah from Nevada in the city of
Wendover on the edge of the
Bonneville Salt Flats. The cities of
West Wendover, Nevada, and Wendover are accessible by I-80's only
business loop in Utah, whose interchange is just south of
Danger Cave. The highway closely follows the historical routes of the
Wendover Cut-off,
Victory Highway, and formerly
Western Pacific Railroad's Feather River Route (now part of the
Union Pacific Railroad Central Corridor) across the salt flats and the larger
Great Salt Lake Desert.
Bonneville Speedway, home to many
land speed records, is accessible from I-80. In the middle of the salt flats is a concrete sculpture,
Metaphor: The Tree of Utah, which stands just off the westbound carriageway of I-80, east of Wendover. Bounded on each sides by military training grounds, the I-80 corridor is overflown by commercial airliners traveling west from
Salt Lake City International Airport. The freeway veers north around the
Cedar Mountains in a small gap between them and the
Lakeside Mountains. Further east, the highway passes the
Stansbury Mountains, which are located in the
Wasatch–Cache National Forest. After the mountain ranges, the freeway arrives at the southern shore of the
Great Salt Lake and closely follows the shore toward the western suburbs of Salt Lake City. However, the historical routes from which the route of I-80 was derived were routed further from the lake, passing through the towns of
Grantsville and
Tooele; these communities are now served by
SR-138 and
SR-36, respectively. After an interchange with SR-36 at
Lake Point, the highway crosses a bottleneck between the
Oquirrh Mountains and the Great Salt Lake.
Salt Lake County and
SR-201 in Salt Lake County While traversing the neck, views can be had from I-80 of the lake and
Antelope Island. After passing the neck, the road forks, with I-80 proceeding toward the north end of Salt Lake City and
SR-201 proceeding toward the south end. Historically, this intersection was the separation of US-40 and
US-50. After the intersection, the freeway corridor is again bottlenecked with the Great Salt Lake to the north and the
Kennecott Utah Copper smelter and
tailings pond to the south. The Kennecott Utah Copper's
Bingham Canyon Mine, which was once considered to be the largest open-pit copper mine, can be seen in the distance. The
Kennecott Garfield Smelter Stack is one of the
tallest freestanding structures in the United States. Along this portion, the freeway passes the historical site of
Saltair. In the southwestern corner of the Spaghetti Bowl is another portion of the UTA TRAX Green Line as it travels towards
West Valley City. After separating from I-15, the freeway continues easterly through
South Salt Lake, loosely following an alignment just south of 2100 South and the UTA
S Line streetcar through the
Sugar House neighborhood and past
Sugar House Park—once the home of the
Sugar House Prison—toward the clockwise terminus of the
I-215 270-degree
beltway around Salt Lake City. It continues through
Parleys Canyon, Between the mouth of the canyon and the Summit County line, the route reenters the
Wasatch National Forest. Both the canyon and summit were named for
Parley P. Pratt, an early settler to the Salt Lake Valley and an early
Mormon leader who was asked to survey a new route across the mountains to replace the route through
Emigration Canyon. Between 1848 and 1851, Pratt surveyed, completed, and operated the Golden Pass toll road through the canyon that today bears his name. Pratt had unsuccessfully solicited for $800 (equivalent to $ in ) to build the road and sold it for $1,500 (equivalent to $ in ). On- and offramps for the Wyoming port-of-entry are located just within Utah. Beyond Parleys Summit lies
Park City, a mining town today better known for its many ski resorts. The
Historic Union Pacific Rail Trail State Park travels in the median between carriageways of I-80 before paralleling the highway until the southern end of
Echo Reservoir. The freeway turns north upon reaching the
Rockport Reservoir at
Wanship following the tributaries of the
Weber River toward Echo Reservoir and Dam. Upon reaching Echo Canyon and the junction with the eastern terminus of the western section of
I-84, the freeway follows the canyon east until it reaches the Wyoming state line near
Evanston. I-80 forms the northeastern border between
Rich and Summit counties. The portion through Echo Canyon follows the historical routes of the
Mormon Trail,
US-30S, and the
first transcontinental railroad. A rest area in the canyon just east of the junction with I-84 features signs pointing out features that were obstacles for both the Mormon pioneers and the railroad construction workers, including Pulpit Rock, which was partially demolished when the I-80 was built through the canyon. ==History==