Interstate 84 in Utah

Interstate 84
Route information
Defined by Utah Code §72-4-114
Maintained by UDOT
Length:	119.77 mi[1] (192.75 km)
Existed:	1956 – present
Major junctions
West end:	I-84 at Idaho state line
	I-15 near Tremonton US-91 in Willard I-15 in Riverdale US-89 in Uintah
East end:	I-80 near Echo
Location
Counties:	Box Elder, Weber, Davis, Morgan, Summit
Highway system
Interstate Highway System Main Auxiliary Suffixed Business State highways in Utah Interstate • US State (Minor • Parks) Scenic ← SR-83 SR-85 →

Interstate 84 (I-84) is a part of the Interstate Highway System that links Portland, Oregon to I-80 near Echo, Utah. The 119.77-mile-long (192.75 km) segment in the U.S. state of Utah is the shortest of any of the three states the western portion of the Interstate Highway passes through, and contains the eastern terminus of the highway. I-84 enters Box Elder County near Snowville before becoming concurrent with I-15 in Tremonton. The concurrent highways travel south through Brigham City and Ogden and separate near the Ogden-Hinckley Airport. Turing east along the Davis County border, I-84 intersects U.S. Route 89 (US-89) and enters Weber Canyon as well as Morgan County. While in Morgan County, I-84 passes the Devil's Gate-Weber Hydroelectric Power Plant and Devil's Slide rock formation. Past Morgan, the highway crosses into Summit County, past the Thousand Mile Tree before reaching its eastern terminus at I-80 near Echo.

Construction of the controlled-access highway was scheduled in late 1957 under the designations Interstate 82S and Interstate 80N. The I-82S designation was only applied on paper for about a year, but the I-80N designation was the highway's official designation until 1977 when it was renumbered I-84 by the American Association of State Highway and Transportation Officials. By 1978, construction of the freeway had been completed across Utah, as well as Oregon and most of Idaho. I-84 is unusual as there are two noncontiguous segments: Oregon, Idaho, and Utah as well as Pennsylvania, New York, Connecticut, and Massachusetts. Average traffic in 2012, along the non-concurrent parts of I-84, ranged from as few as 6,655 vehicles traveling along I-84 at the interchange with SR-86 in Henefer, and as many as 18,945 vehicles used the highway at the SR-26 interchange in Riverdale.

Route description

Out of the three states that the western portion of I-84 passes through, the 119.77-mile-long (192.75 km) segment in Utah is the shortest. By comparison, the longest stretch of western I-84 through a single state is the 375.17-mile-long (603.78 km) segment in Oregon. I-84 also has a noncontiguous eastern segment that passes through Pennsylvania, New York, Connecticut, and Massachusetts: all four of these segments are shorter than the Utah segment.^[1]

Every year, the Utah Department of Transportation (UDOT) conducts a series of surveys on its highways in the state to measure traffic volume. This is expressed in terms of average annual daily traffic (AADT), a measure of traffic volume for any average day of the year. In 2012, UDOT calculated that as few as 6,655 vehicles traveled I-84 at the interchange with SR-86 in Henefer, and as many as 18,945 vehicles used the highway at the SR-26 interchange in Riverdale.^[2] Between 27 and 57 percent of the traffic recorded consisted of trucks.^[3] These counts are of the portion of the freeway in Utah and are not reflective of the entire Interstate, or of its concurrency with I-15. As part of the Interstate Highway System,^[4] 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.^[5]

Western segment

Crossing the Idaho-Utah state line, I-84 enters Box Elder County and the Curlew Valley near farmland that utilizes center pivot irrigation before intersecting SR-30 at a diamond interchange.^[6] The town of Snowville is crossed before passing to the north of the Hansel Mountains and the North Promontory Mountains. The town of Howell, accessible from an interchange with SR-83, lays to the southeast of Blue Creek Reservoir in the Blue Creek Valley. Access to the Golden Spike National Historic Site is provided by SR-83 south of Howell. The Blue Spring Hills form the southern border of Howell as I-84 continues southeast.^[7] Additional center irrigation farmland is passed before giving way to more traditional farmland outside of the city of Tremonton,^[6] where a trumpet interchange marks where I-15 turns north towards Malad City and Pocatello.^[8] Heading southeast from this interchange, I-84 and I-15 are concurrent for just over 38 miles (61 km).^[9]

Concurrency with I-15

Northbound along I-15/84 in Ogden

Concurrent highways I-15/84 continue south, parallel to rail belonging to the Union Pacific Railroad (UP) past the Wellsville Mountain Wilderness, to an interchange at 1100 West in Brigham City, also known as US-91, which once in Brigham City becomes concurrent with US-89 and the two highways travel northeast from Brigham City into Box Elder Canyon towards Logan in the heart of the Cache Valley. US-89 closely parallels I-15/84 east,as the highways pass Willard Bay, the Willard Bay State Park and Bear River Migratory Bird Refuge before crossing into Weber County.^[6][7]

Upon entering Weber County the rail line that the highway has paralleled since Tremonton splits off eastwards near Defense Depot Ogden, as the concurrent highways continue south past Farr West and Slaterville before a Southern Pacific Railroad rail line, which traverses the Great Salt Lake on a causeway, crosses under the freeway. The city of Ogden is bypassed by the Interstates, with US-89 serving downtown. US-89 is accessible via interchanges with SR-39, SR-79 and SR-104 in addition to I-84 further southeast. I-84 splits from I-15 at the south end of the Ogden-Hinckley Airport, with I-15 continuing south towards Salt Lake City and Provo.^[6][10]

Eastern segment

The Thousand Mile Tree

Splitting from I-15 near Roy, I-84 passes between Hill Air Force Base, which is to the south of the highway, and Washington Terrace before clipping the extreme northern portions of Davis County.^[10] While in Davis County, I-84 intersects 475 East, also known as the Adams Avenue Parkway,^[6] before coming to a hybrid partial cloverleaf/half-diamond interchange with US-89 along the Davis-Weber county line.^[10][11]

I-84 follows the Weber River into Weber Canyon, Morgan County, and the Wasatch-Cache National Forest. Once in the canyon, the carriageways of the highway split to accommodate the Devil's Gate-Weber Hydroelectric Power Plant. Following the river south, I-84 exits the forest and enters the county seat of Morgan. Leaving the city the highway turns back east,^[6][12] passing Devil's Slide, an unusual rock formation just off the freeway.^[13]

Upon entering Summit County, I-84 passes the Thousand Mile Tree, planted by Union Pacific Railroad workers to mark the construction of 1,000 miles (1,600 km) of rail from its origin in Omaha, Nebraska.^[14][15] The tree was said to be the only pine tree between Omaha and Salt Lake City.^[16] Another tree was planted as the original tree had died in 1900 and was removed in 1926 to during the conversion from single track to double track through the canyon.^[17][18] Past the tree the freeway passes through the town of Henefer before terminating at a directional T interchange with I-80 just south of the census-designated place of Echo. Immediately south of the interchange is Echo Reservoir and Echo Dam.^[6][19]

History

I-84 approaching its eastern terminus

Earlier roads

Most of the original routing of what is now I-84 existed as early as 1923; however the portion of now I-84 into Idaho was not yet constructed.^[20] In 1926, much of the route was signed as US-30S, from the now eastern terminus at I-80 (US-530 then), northwest into Ogden. Between Ogden and Brigham City, the highway was to be concurrent with US-91, then US-30S split off northwest to the Idaho border.^[21] The entire western branch of US-30S was an unimproved road, however the concurrency into Ogden was paved. The remainder of the route to its now terminus was mostly graded with a few improved sections,^[22] and by 1937, the entire route was paved.^[23]

Current road

The first Utah State Route to have the number 84 is what is now known as SR-126. SR-126 was originally numbered SR-84 until the 1977 renumbering of Utah State highways. Previously, the freeway's legislative designation was SR-3.^[24] Like the other two main Interstate Highways in Utah, I-15 (the Veterans Memorial Highway) and I-80 (the Purple Heart Trail), I-84 has also been given a special name of "Vietnam Veterans Memorial Highway". House Bill HB275 authorizing the name designation was signed into law by Utah Governor Gary Herbert on March 30, 2015.^[25][26] The highway loosely follows the path of the First Transcontinental Railroad.^[27] The original routing of US-30S had the highway passing into Idaho west of Black Pine Peak however,^[28] the new I-84 was constructed to the east. The original roadways are now numbered SR-30, SR-42 and Idaho State Highway 2847.^[6][29]

Interstate 80N
Location:	Idaho state line to Echo
Existed:	1958–1977[30][31]

Passage of the Federal Aid Highway Act of 1956 formed the Interstate Highway System,^[32] however only the western segment of now I-84 was approved at this time, and a designation of I-82S was assigned to a then unconstructed controlled-access highway across Box Elder County in 1957.^[33] The eastern segment of the highway was added later in 1957,^[34] and the route was numbered I-80N by 1958.^[30] By 1968, portions of the western half of the freeway had been completed, along with the segment between Tremonton and Brigham City. A portion of the freeway was completed around Morgan as well.^[35] By 1971, most of the western portions of the freeway had been constructed with two sections remaining that had at-grade intersections. Along the concurrency, there were gaps between Brigham City and Pleasant View, and one small gap near the Devil's Slide.^[36]

The I-80N designation was changed to I-84 in 1977 by the American Association of State Highway and Transportation Officials, over objections from the Washington State Department of Transportation and the Idaho Transportation Department, and with the support of UDOT and the Oregon Department of Transportation.^[24][31] By 1978, construction of I-84 was complete across Utah, Oregon and most of Idaho.^[37]

In 1994 I-84 was planned to be used to transport low-level radioactive waste from the Idaho National Engineering Laboratory to Waste Isolation Pilot Plant in Carlsbad, New Mexico via Wyoming.^[38] This did not start until 1999 however due to the delay in the opening of the New Mexican plant.^[39] A $20 million (equivalent to $33.9 million in 2015)^[40] reconstruction of the US-89 interchange at the mouth of Weber Canyon was financed partly by the funding obtained by the state in preparation for the 2002 Winter Olympics in 1998,^[41] and was scheduled to begin in 2000.^[42] Reconstruction of a 10-mile-long (16 km) segment of I-84 between Mountain Green and Morgan was done between 2004 and 2005 at a cost of $19 million (equivalent to $25.3 million in 2015).^[40][43] One of the sub-contractors on the job was found guilty of lying about sub-par work done on installation of roadside impact absorbers along this stretch.^[44]

Exit list

County	Location	mi[9]	km	Exit	Destinations	Notes
Box Elder		0.000	0.000	Idaho–Utah state line I-84 continues into Idaho
		4.660	7.500	5	SR-30 west – Park Valley, Elko	West end of SR-30 overlap; Former US-30S
	Snowville	7.125	11.467	7	Snowville
		11.978	19.277	12	Ranch Exit
		15.808	25.441	16	Hansel Valley
		17.385	27.978	17	Rattlesnake Pass
		20.317	32.697	20	Blue Creek
		24.457	39.360	24	Pocatello Valley
	Howell	26.567	42.755	26	SR-83 south – Howell, ATK	Access to Golden Spike National Historic Site
		32.414	52.165	32	Ranch Exit
		39.508	63.582	39	Garland, Bothwell
	Bothwell Junction	40.824	65.700	40	SR-102 – Tremonton, Bothwell
		42.012	67.612	41	I-15 north (SR-30 east) – Pocatello	West end of I-15 overlap; east end of SR-30 overlap; no exit number westbound
				I-84 overlaps Interstate 15 for 38.309 mi (61.652 km)
Weber	Riverdale	81.043	130.426		I-15 south – Salt Lake City	East end of I-15 overlap; westbound exit is via exit 81
		81.727	131.527	81	SR-26 – Riverdale
Davis	Uintah	84.594	136.141	85	Uintah, South Weber (Adams Avenue Parkway)	Adams Avenue Parkway is a private toll road
Davis–Weber county line	Uintah Junction	87.771	141.254	87	US-89 – South Ogden, Salt Lake City, Ogden	Signed as exits 87A (north) and 87B (south) westbound
Morgan		91.240	146.837	Rest area Eastbound exit and entrance only
		92.339	148.605	92	SR-167 – Mountain Green, Huntsville	Westbound exit is via exit 96
		93.904	151.124	Rest area Westbound exit and entrance only
		96.504	155.308	96	Stoddard, Peterson
	Morgan	103.333	166.298	103	SR-66 – Morgan
		106.173	170.869	106	Ranch Exit
		108.272	174.247	108	Taggart
		111.313	179.141	111	Croydon	Former SR-158
		110.761	178.253	Devil's Slide View Area
Summit		112.739	181.436	112	Henefer (SR-86)
	Henefer	115.399	185.717	115	Henefer, Echo (SR-65)
		119.773	192.756	120	I-80 – Salt Lake City, Cheyenne	I-80 exit 168; signed as exits 120A (east) & 120B (west); eastern terminus; directional T interchange.
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus       Incomplete access

See also

• U.S. Roads portal
• Utah portal

References

1. Adderly, Kevin (January 19, 2012). "Table 1: Main Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways". FHWA Route Log and Finder List. Federal Highway Administration. OCLC 47914009. Retrieved December 27, 2013.
2. Staff (2012). Traffic on Utah Highways (PDF) (Report). Utah Department of Transportation. p. 16. Retrieved December 27, 2013.
3. Staff (2012). Truck Traffic on Utah Highways (PDF) (Report). Utah Department of Transportation. p. 15. Retrieved December 25, 2013.
4. Slater, Rodney E. (Spring 1996). "The National Highway System: A Commitment to America's Future". Public Roads 59 (4). Retrieved January 24, 2011.
5. National Highway System: Utah (PDF) (Map). 1:772200. Federal Highway Administration. November 18, 2013. Retrieved December 27, 2013.
6. Google (December 27, 2013). "Interstate 84 Overview" (Map). Google Maps. Google. Retrieved December 27, 2013.
7. Box Elder County (Map). 1:29040. General Highway Map. Utah Department of Transportation. 2005. p. 6. Retrieved December 27, 2013.
8. Box Elder County (Map). 1:29040. General Highway Map. Utah Department of Transportation. 2005. p. 7. Retrieved December 27, 2013.
9. "Route 84". Highway Reference. Utah Department of Transportation. January 2, 2013. Retrieved December 27, 2013. External link in |work= (help)
10. Weber County (Map). 1:22440. General Highway Map. Utah Department of Transportation. 2005. p. 1. Retrieved December 27, 2013.
11. Davis County (Map). 1:22440. General Highway Map. Utah Department of Transportation. 2005. Retrieved December 27, 2013.
12. Morgan County (Map). 1:29040. General Highway Map. Utah Department of Transportation. 2005. Retrieved December 27, 2013.
13. Powell, Allan Kent (2003). The Utah Guide (3rd ed.). Golden, Colo.: Fulcrum Publishing. p. 84. ISBN 9781555911140. Retrieved December 27, 2013.
14. Leng, Sir John (1877). America in 1876: Pencillings During a Tour. Dundee, Scotland: Dundee Advertiser Office. p. 109. OCLC 1658991. Retrieved December 28, 2013.
15. Hayden, F.V.; Davis, Daniel M. "Sun Pictures of Rocky Mountain Scenery, Photographic Collection". Utah State University Special Collections and Archives. Retrieved January 6, 2007.
16. Wilcox, H. K. W. (1870). "Famous Trees". Appleton's Journal of Literature, Science and Art (D. Appleton & Company): 675. OCLC 8241845. Retrieved December 27, 2013.
17. Staff. "Historic Sites". Morgan County Historical Society. 2007. Retrieved December 27, 2013.
18. Smith, Linda H. (1999). A History of Morgan County (PDF). Utah Centennial County History. Salt Lake City: Utah State Historical Society. p. 260. ISBN 978-0913738368. Retrieved December 27, 2013.
19. Summit County (Map). 1:22440. General Highway Map. Utah Department of Transportation. 2005. p. 3. Retrieved December 27, 2013.
20. Map of Strategic Routes between Salt Lake City, Utah and California (Map). 1:2500000. Cartography by Matthews-Northrup Works. Lincoln Highway Association. 1923. OCLC 36006905. Retrieved December 27, 2013.
21. United States System of Highways Adopted for Uniform Marking by the American Association of State Highway Officials (Map). 1:7,000,000. Cartography by U.S. Geological Survey. Bureau of Public Roads. November 11, 1926. OCLC 32889555. Retrieved December 27, 2013.
22. Utah (northern) (Map). 1:237600. Rand McNally Junior Road Map. Rand McNally. 1926. OCLC 39724225. Retrieved December 27, 2013.
23. Texaco Road Map Idaho, Montana, Wyoming (Map). 1:1,774,080. Cartography by Rand McNally. Texaco. 1937. § L5-M7. OCLC 52950564. Retrieved December 26, 2013.
24. "Route 84". Highway Resolutions. Utah Department of Transportation. November 2007. Retrieved September 21, 2008. External link in |work= (help)
25. http://le.utah.gov/~2015/bills/static/HB0275.html
26. Utah's Special Highways (Map). Not to scale. Utah Department of Transportation. Retrieved December 28, 2013.
27. United States Congress (1969). Congressional Record. Volume 115, Part 2. Government Printing Office. p. 29631. Retrieved December 27, 2013.
28. Highway Map of Utah (Map). 1:1203840. Cartography by H.M. Gousha Company. Shell Oil Company. § C2. Retrieved December 26, 2013.
29. Idaho Official State Highway Map (PDF) (Map). M5-6. Idaho Transportation Department. Retrieved December 26, 2013.
30. Official Route Numbering for the National System of Interstate and Defense Highways as Adopted by the American Association of State Highway Officials (Map). Scale not Given. Public Roads Administration. June 27, 1958. Retrieved December 27, 2013.
31. Staff (August 13, 1977). "Interstate 80 to become 84". Deseret News (Salt Lake City). pp. A3. OCLC 367900151.
32. Lewis, Tom (1997). Divided Highways: Building the Interstate Highways, Transforming American Life. New York: Viking. pp. 120–1, 136–7. ISBN 0-670-86627-X.
33. Official Route Numbering for the National System of Interstate and Defense Highways as Adopted by the American Association of State Highway Officials (Map). Scale not given. Cartography by Public Roads Administration. Public Roads Administration. August 14, 1957. Retrieved December 26, 2013.
34. Routes to be Added to the National System of Interstate and Defense Highways (Map). Scale not given. Public Roads Administration. October 17, 1957. Retrieved December 27, 2013.
35. Western United States (Map). 1:3104640. Cartography by Rand McNally & Co. Union Oil Company of California. 1968. § H7-8.
36. Utah Official Highway Map (Map). 1:1,102,464. Cartography by Rand McNally. State Road Commission of Utah. 1971. § B4-C5.
37. Staff (December 3, 1978). "Other Projects Get $5 Billion in Interstate Road 'Trades': Fewer Than 11,000 Miles Complete". The New York Times. OCLC 1645522. Retrieved December 27, 2013 – via ProQuest. (subscription required (help)).
38. Staff (September 1, 1993). "N-Waste shipments to Pass Through N. Utah in 1994". The Salt Lake Tribune. Associated Press. p. C3. OCLC 8086936. Retrieved December 27, 2013 – via ProQuest. (subscription required (help)).
39. Staff (March 23, 1999). "Judge's Ruling May Open Path Through Utah for Nuke Waste". The Salt Lake Tribune. Associated Press. p. A8. OCLC 8086936. Retrieved December 27, 2013 – via ProQuest. (subscription required (help)).
40. United States nominal Gross Domestic Product per capita figures follow the Measuring Worth series supplied in Johnston, Louis; Williamson, Samuel H. (2016). "What Was the U.S. GDP Then?". MeasuringWorth. Retrieved April 10, 2016. These figures follow the figures as of 2015.
41. Gorrell, Mike (October 28, 1998). "Fed Funds Pave Way For Roads; Most of $90M transportation grant will go to Olympic highway work; Grant Provides $75M for Olympic Roads". The Salt Lake Tribune. p. A1. OCLC 8086936. Retrieved December 27, 2013 – via ProQuest. (subscription required (help)).
42. Gorrell, Mike (October 19, 1999). "As Feds Divvy Up Last of Highway Funds, SLOC Holds Breath". The Salt Lake Tribune. p. B2. OCLC 8086936. Retrieved December 27, 2013 – via ProQuest. (subscription required (help)).
43. "Granite Construction Awarded $19.0 Million Highway Reconstruction Project in Utah" (Press release). PR Newswire. December 22, 2003. OCLC 44297296. Retrieved December 27, 2013 – via ProQuest. (subscription required (help)).
44. Manson, Pamela (July 8, 2009). "Orem construction company admits lying". The Salt Lake Tribune. OCLC 8086936. Retrieved December 27, 2013 – via ProQuest. (subscription required (help)).

External links

Route map: Bing / Google

• Media related to Interstate 84 in Utah at Wikimedia Commons
• Interstate 84 in Utah on AARoads