 Interstate 84 | |
|---|---|
 I-84 highlighted in red | |
| Route information | |
| Length | 769.62 mi[1] (1,238.58 km) |
| Existed | 1956 (as I-80N)–present |
| NHS | Entire route |
| Major junctions | |
| West end |   I-5 /US 30 inPortland, OR |
| Major intersections |
|
| East end |   I-80 /US 189 inEcho, UT |
| Location | |
| Country | United States |
| States | Oregon,Idaho,Utah |
| Highway system | |
Interstate 84 (I-84) is anInterstate Highway in thenorthwestern United States. The highway runs almost 770 miles (1239 km) fromPortland, Oregon, to a junction withI-80 nearEcho, Utah. The highway serves and connects Portland,Boise, andOgden, Utah. With connections to other highways, I-84 connects these cities to points east and also serves as part of a corridor betweenSeattle andSalt Lake City. The sections running through Oregon and Idaho are also known as the Vietnam Veterans Memorial Highway.[2][3]
The highway originally served as a fork of I-80 to serve thePacific Northwest, and was originally numberedInterstate 80N. It was generally built along the corridor ofU.S. Route 30 (US 30) andUS 30S, which themselves largely followed theOregon Trail; the US 30S designation was decommissioned in the 1970s after the freeway replacement was mostly complete. The highway was signed with the I-84 designation in 1980, when a 1977 change in guidelines took effect that discouraged highway numbers with directional suffixes.[4] The renumbering resulted in two highways being numbered I-84, with theother located in theNortheastern United States.
| mi[1] | km | |
|---|---|---|
| OR | 379 | 610 |
| ID | 275.74 | 443.76 |
| UT | 118.71 | 191.05 |
| Total | 769.62 | 1,238.58 |
In thePortland metropolitan area, I-84 is sometimes referred to as the "Banfield Freeway" or simply "the Banfield", although the official name is the Banfield Expressway. This freeway is named after Thomas H. "Harry" Banfield (1885–1950), the chairman of the Oregon Transportation Commission from 1943 to 1950. As I-84 heads east, it also follows US 30 in a majority of I-84 from Portland, Oregon, to near Rupert, Idaho, with splits being variant in Oregon and Idaho, but before leaving Portland, there is a junction withI-205, along with citiesGresham,Fairview,Wood Village andTroutdale.[clarification needed]
Immediately after leaving Troutdale, I-84 and US 30 runs east along the south bank of theColumbia River (and the northern Oregon border, as well) for nearly 150 miles (240 km) with the first 80 miles being in theColumbia River Gorge National Scenic Area, running from Troutdale to theDeschutes River, passing through the cities ofHood River andThe Dalles in the Scenic Area. It also passes throughBiggs Junction, Rufus,Arlington, andBoardman outside of the Scenic Area before heading southeast to the junction with southern end ofI-82 immediately southeast of theUmatilla Chemical Depot nearHermiston. From the junction it continues southeast on toPendleton.
East of Pendleton, I-84 climbs Emigrant Hill, a 6% grade, into theBlue Mountains. The westbound lanesswitchback twice on its descent into Pendleton. Eastbound lanes feature the tightest curves allowed on the Interstate Highway system, even though those curves are on the uphill (eastbound) direction. This grade is also well known because of the distance between eastbound and westbound lanes, nearly 2 miles (3.2 km) between the opposite directions of travel at some points.
The road summits at 4,193 feet (1,278 m)above sea level before descending to theGrand Ronde River andLa Grande. It passes byNorth Powder andBaker City and through theBurnt River canyon. AroundHuntington, it crosses into theMountain Time Zone then briefly follows the southwest bank of theSnake River (Brownlee Reservoir), then continues toOntario before crossing the Snake River intoIdaho.
On March 1, 2016, the speed limit from The Dalles to Ontario was raised to 70 miles per hour (110 km/h), while the truck speed was raised to 65 miles per hour (105 km/h).[5]
I-84 enters Idaho by crossing theSnake River atOntario, Oregon. From there, it continues on to the major cities of theTreasure Valley (orBoise metropolitan area) includingCaldwell,Nampa,Meridian, andBoise (whereI-184 connects travelers to downtown). From Boise, I-84 continues southeast passing near several small cities (Mountain Home,Glenns Ferry, andJerome) on its way toTwin Falls.
Just east of Jerome, I-84 passes within five miles (8.0 km) of Twin Falls, but does not cross theSnake River Canyon or intoTwin Falls County. Access to Twin Falls is afforded by an intersection withUS 93 at Exit 173; US 93 southbound crosses the Snake River via thePerrine Bridge.
After Twin Falls, I-84 continues throughBurley andHeyburn. Approximately seven miles (11 km) east ofDeclo in ruralCassia County, I-84 meets the western terminus of the western section ofI-86. While I-86, along with US 30 heads east, then northeast toAmerican Falls andPocatello (following theOregon Trail), I-84 heads southeast to the border withUtah.
In 2014, the speed limit on rural sections of I-84 in Idaho was raised to 80 miles per hour (130 km/h).[6]
From Idaho, I-84 enters Utah at a point approximately 7 miles (11.3 km) fromSnowville inBox Elder County. It proceeds southeast through Rattle Snake Pass towardsBrigham City where I-84 joinsI-15 (just west ofTremonton) for its next 40 miles (64 km).
Just north of Brigham City, atCorinne, Utah, I-84 joins the route of theFirst transcontinental railroad which the highway follows to its terminus. I-15/I-84 heads south to the cities of the Wasatch Front (Or the Ogden-Clearfield Utah Metropolitan part) passing through several smaller communities and then the west side ofOgden before I-84 separates towards Cheyenne, Wyoming, while I-15 heads to Salt Lake City, I-84 follows theWeber River east.
As the freeway gradually ascends throughWeber Canyon it also passes through several small farming communities, includingMorgan, where theBrowning Arms Company headquarters can be seen from the freeway. Also visible in the canyon isDevil's Slide, an unusual rock formation just off the freeway.[7] Farther up the canyon is theThousand Mile Tree, planted byUnion Pacific Railroad workers to mark 1,000 miles (1,600 km) from the railroad's origin inOmaha, Nebraska.[8]
The freeway ends atEcho, a near ghost town that before served as a stopover for the railroad, at a junction withInterstate 80, to Cheyenne, Wyoming, and US 189, to Jackson, Wyoming. Also near the junction are Echo Reservoir andEcho Dam.
The Utah sections of I-84 that are not concurrent withInterstate 15 are defined at Utah Code Annotated § 72-4-114(4).[9]
The Portland to Utah corridor was proposed as one of the national "toll superhighways" in a 1939 report by theBureau of Public Roads.[10] It was formally included in theInterstate Highway System, created in 1956, and was originally proposed to be numbered as Interstate 82;[11] however, it was never signed with this designation, and theInterstate 82 designation was later assigned to a different road that connectsEllensburg, Washington, toYakima, Washington, theTri-Cities region, andHermiston, Oregon. The freeway was assigned the designation of I-80N in the 1958 plan, in part to correspond with US 30.[12][13] The Portland segment of then-I-80N was proposed to run on theMount Hood Freeway and a section ofI-205.[14][15] Plans for this were officially dropped in 1974 after a successfulfreeway revolt.[16]
TheAmerican Association of State Highway and Transportation Officials established guidelines recommending that "suffixed" highways, such as I-80N, be renumbered. In 1977, Idaho officials recommended that I-80N be renumbered to I-84. The motion was seconded by officials in Utah (who initially proposed this as I-82), but opposed by Oregon and Washington. The motion passed on July 7, 1977, and the states were given until July 1, 1980, to implement a coordinated renumbering strategy.[4] After renumbering, I-84 violated the Interstate Highway Numbering Convention by being south of the modern incarnation of I-82.[17]
All junctions withUS 30 are not listed.[18]
I-5 /US 30 inPortland
I-205 in Portland
US 30 /US 197 inThe Dalles
US 97 inBiggs Junction
US 730 nearBoardman
I-82 nearHermiston
US 395 nearStanfield; joined untilPendleton
US 95 nearFruitland
US 20 /US 26 nearMiddleton, joined untilCaldwell
I-184 inBoiseUS 20 /US 26 in Boise; joined untilMountain Home andBliss respectively
US 93 nearTwin Falls
I-86 /US 30 nearDeclo
I-15 inTremonton; joined untilRiverdale
US 91 inBrigham City
US 89 inSouth WeberI-80 /US 189 inEcho
Geographic data related toInterstate 84 (Oregon–Utah) atOpenStreetMap PrimaryInterstate Highways | |
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| Signed | |
| Unsigned | |
| Lists | |
| Other | |
Routes initalics are no longer a part of the system. Major Interstates are highlighted. | |
Auxiliary routes of highways designated as Interstate 84 | ||
|---|---|---|
| Oregon–Utah segment | | |
| Pennsylvania–Massachusetts segment | ||
1Former | ||
| International | |
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| Geographic | |
