Interstate 184 (I-184) is a short

auxiliary Interstate Highway Auxiliary Interstate Highways (also called three-digit Interstate Highways) are a supplemental subset of the freeways within the Interstate Highway System of the United States. Auxiliary routes are generally classified as spur routes, which con ...

Boise, Idaho Boise (, , ) is the capital and most populous city of the U.S. state of Idaho and is the county seat of Ada County. On the Boise River in southwestern Idaho, it is east of the Oregon border and north of the Nevada border. The downtown are ...

, United States. It is a spur route of

I-84 Interstate 84 may refer to: * Interstate 84 (Oregon–Utah), passing through Idaho, formerly known as Interstate 80N * Interstate 84 (Pennsylvania–Massachusetts) Interstate 84 (I-84) is an Interstate Highway in the Northeaster ...

that connects the freeway to

Downtown Boise Downtown Boise is the central business district of Boise, Idaho, located north of the Boise River. It is the largest city center in the state of Idaho. Economy Largest private sector employers * Note: this list only includes companies who hav ...

, terminating at US Highway 20 (US 20) and US 26.

Route description

Interstate 184 westbound from Orchard Street, Boise, ID

I-184, also known as the Boise Connector, begins at the "Flying Wye" interchange with

and US 30 in southwestern Boise. The six-lane freeway travels northeast through suburban Boise, crossing over a spur railroad near an interchange with Franklin Street on the south side of the Boise Towne Square shopping mall. I-184 intersects Curtis Road near the Saint Alphonsus Regional Medical Center and turns due east along Fairview Avenue, which acts as a

frontage road A frontage road (also known as an access road, outer road, service road, feeder road, or parallel road) is a local road running parallel to a higher-speed, limited-access road. A frontage road is often used to provide access to private drivew ...

. On the west side of the

Boise River The Boise River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. , accessed May 3, 2011 tributary of the Snake River in the Northwestern United States. It drains a rugged portion of the Sawtooth Range in sou ...

in Rotary Park, I-184 terminates after an interchange with US 20 and US 26, which serve northwestern Boise on Chinden Boulevard. US 20 and US 26 supersede I-184 and cross into

, where it splits into Front and Myrtle streets. I-184 is the only auxiliary Interstate Highway in Idaho and the state's shortest, at . The highway is maintained by the

Idaho Transportation Department The Idaho Transportation Department (ITD) is the state of Idaho governmental organization responsible for state transportation infrastructure. This includes ongoing operations and maintenance as well as planning for future needs of the state and it ...

(ITD), which conducts an annual survey of traffic on certain highway segments that is expressed in terms of

annual average daily traffic Annual average daily traffic, abbreviated AADT, is a measure used primarily in transportation planning, transportation engineering and retail location selection. Traditionally, it is the total volume of vehicle traffic of a highway or road for a y ...

(AADT), a measure of traffic volume for any average day of the year. The sole traffic recording device on I-184 reported a daily average of 81,140 vehicles on the highway in 2017.

History

The Boise Connector was planned in the early 1960s to connect the Boise freeway bypass to Downtown Boise and its inner neighborhoods. One version of the plan proposed a full loop bisecting Downtown Boise to carry I-80N, but it was rejected in favor of a less costly spur route. The westernmost section of the connector, including a sprawling wye interchange with I-80N, was opened to traffic on December 12, 1968, a year before the rest of the bypass. Parts of the connector were signed as part of State Highway 55 (SH-55) until it was realigned in the 1980s. The freeway was numbered Interstate 180N (I-180N) until October 13, 1979, when I-184 was adopted to match I-84, which was planned to succeeded I-80N. It was the only signed suffixed auxiliary Interstate Highway in the nation. When I-80N was redesignated I-84, this highway was redesignated Interstate 84 Business (I-84 Bus) through Boise. The current I-184 designation was signed when the construction upgrading the route to

Interstate standards Standards for Interstate Highways in the United States are defined by the American Association of State Highway and Transportation Officials (AASHTO) in the publication ''A Policy on Design Standards: Interstate System''. For a certain highway to ...

was completed in 1990. The new bridge across the Boise River was opened on August 7, 1992, replacing a pair of smaller bridges to the north. The westernmost segment of I-184, including the Flying Wye interchange, was rebuilt from 1999 to 2004 to accommodate an additional set of lanes. The project cost $86 million (equivalent to $ in ) and was delayed approximately six months due to financial constraints and delays in bridge construction in the initial phase of the project.

Exit list

References

External links

{{authority control 84-1 84-1 1 Transportation in Ada County, Idaho Boise, Idaho