SR 14 was established in 1968 as the successor to US 830, created in 1926 with the original United States Numbered Highways, and Primary State Highway 8 (PSH 8). PSH 8 was added to the state highway system in 1905 as a short road along the Columbia River between Washougal and Lyle and was extended westwards to Vancouver and eastwards to Maryhill by 1913. PSH 8, designated as the Evergreen Highway, was extended east to the Tri-Cities in 1949 and this section was retained during the 1964 state highway renumbering and the decommissioning of US 830.
Every year, the Washington State Department of Transportation (WSDOT) conducts a series of surveys on its highways in the state to measure traffic volume. This is expressed in terms of annual average daily traffic (AADT), which is a measure of traffic volume for any average day of the year. In 2012, WSDOT calculated that the busiest section of SR 14 was east of its interchange with I-205 in Vancouver, serving 72,000 vehicles, while the least busiest section of the highway was in Maryhill, serving 500 vehicles.[22] SR 14 between Vancouver and Maryhill is designated as part of the National Highway System for its whole length,[23] classifying it as important to the national economy, defense, and mobility.[24] WSDOT designates the same corridor as a Highway of Statewide Significance,[25] which includes highways that connect major communities in the state of Washington.[26]
The North Bank Highway was constructed with macadam pavement and was dedicated from Lyle to Dallesport in 1934,[38] shortly before State Road 8 was re-designated as PSH 8 and the Evergreen Highway in 1937,[39] traveling east from Vancouver to Mayhill and north to Yakima.[40] SSH 8E, a branch of PSH 8, was also established in 1937 and ran east from PSH 8 in Maryhill to Paterson and north to PSH 3 in Prosser.[40][41] SSH 8E was replaced by the Maryhill–Kennewick branch of PSH 8 in 1943,[42] amidst proposals to extend the Evergreen Highway to the Tri-Cities in 1949.[43]US 197, a spur of US 97, was created in 1952 and became concurrent with US 830 and PSH 8 from the Dallesport area to a junction with its parent route in Maryhill.[44] A section of the winding PSH 8 between Maryhill and Roosevelt was replaced with a new highway running along the north bank of the river in June 1964.[45]
The western terminus at I-5 in Vancouver was rebuilt in 1984 with more ramps to allow for fully-directional navigation, at the cost of land from Fort Vancouver Park.[54] Several new interchanges were built in the late 1980s in eastern Vancouver to bring SR 14 to full grade separation.[55]
The Vancouver Land Bridge, a pedestrian bridge over SR 14 with earthen approaches, was completed in 2008 near Fort Vancouver. It was built as part of the Confluence Project, following the route of an ancient Native American trail while also providing access to the Columbia River waterfront from Fort Vancouver.[56]
SR 14 has a 0.39-mile-long (0.63 km) spur route in Maryhill that connects the eastbound lane of the main highway to US 97 northbound.[1][20] The spur route was established in 1991 during a re-alignment of the two highways in Maryhill and, during its annual AADT survey, WSDOT calculated that 1,400 vehicles used the highway in 2012.[22]
^Washington State Legislature (January 26, 1905). "Chapter 7: Providing for the Establishment and Repair of Certain State Highways". Session Laws of the State of Washington (1905 ed.). Olympia, Washington: Washington State Legislature. p. 22. Retrieved April 23, 2013. For the building of a State wagon road in Klickitat, Skamania and Clarke Counties as follows: Beginning at Lyle in Klickitat County, Washington, and running thence westerly by the most practicable course along the north bank of the Columbia river and above high water mark, at Washougal in Clarke County, Washington, the sum of $15,000.
^Washington State Legislature (March 13, 1907). "Chapter 151: Providing for the Establishment, Construction and Maintenance of State Roads and Making Appropriations for Certain State Roads". Session Laws of the State of Washington (1907 ed.). Olympia, Washington: Washington State Legislature. pp. 310–311. Retrieved April 23, 2013. State Road No. 8, or the Columbia River road: This road shall begin at the town of Washougal in Clarke county, Washington, and run thence over the line as surveyed for such state road through Clarke and Skamania counties, and thence over the most practicable route to the town of Goldendale, in Klickitat county.
^Washington State Legislature (March 17, 1913). "Chapter 96: Establishing a Secondary Highway". Session Laws of the State of Washington (1913 ed.). Olympia, Washington: Washington State Legislature. p. 277. Retrieved April 23, 2013. Extension of secondary highway No. 8, beginning at the town of Washougal, in Clarke county, the present western terminus of secondary highway No. 8, and extending westerly by the most feasible route to Vancouver, Washington. Also commencing at the town of Goldendale, in Klickitat county, the present eastern terminus of said road, and extending the same northeasterly by the most feasible route to Mabton, in Yakima county.
^Washington State Legislature (March 12, 1919). "Chapter 92: Public Highway Appropriations". Session Laws of the State of Washington (1919 ed.). Olympia, Washington: Washington State Legislature. pp. 223–226. Retrieved April 23, 2013.
^Washington State Legislature (March 19, 1923). "Chapter 185: Primary and Secondary State Highways". Session Laws of the State of Washington (1923 ed.). Olympia, Washington: Washington State Legislature. p. 629. Retrieved April 23, 2013. A primary state highway, to be known as State Road No. 8 or the North Bank Highway, is established as follows: Beginning at Vancouver, in Clarke County, thence by the most feasible route in an easterly direction through Stevenson, Underwood, Lyle, Maryhill; thence in a northerly direction through Goldendale to a connection with State Road No. 3 at or in the vicinity of Buena in Yakima County.
^Washington State Legislature (March 17, 1937). "Chapter 190: Establishment of Primary State Highways". Session Laws of the State of Washington (1937 ed.). Olympia, Washington: Washington State Legislature. pp. 937–938. Retrieved April 23, 2013. A primary state highway to be known as Primary State Highway No. 8, or the Evergreen Highway, is hereby established according to description as follows: Beginning at Vancouver on Primary State Highway No. 1, thence in an easterly direction by the most feasible route by way of Stevenson to Goldendale, thence in a northeasterly direction by the most feasible route by way of Satus Pass to a junction with Primary State Highway No. 3, southeast of Yakima.
^Washington State Legislature (March 18, 1937). "Chapter 207: Classification of Public Highways". Session Laws of the State of Washington (1937 ed.). Olympia, Washington: Washington State Legislature. p. 1005. Retrieved April 23, 2013. Secondary State Highway No. 8E; beginning at a junction with Primary State Highway No. 8 in the vicinity south of Goldendale, thence in an easterly direction by the most feasible route to the north of the Columbia river to Paterson, thence in a northerly direction by the most feasible route to Prosser on Primary State Highway No. 3.
^Washington State Legislature (March 20, 1943). "Chapter 239: Public Highways". Session Laws of the State of Washington (1943 ed.). Olympia, Washington: Washington State Legislature. p. 715. Retrieved April 23, 2013. There is hereby established an extension to Primary State Highway No. 8, described as follows: Beginning in the vicinity of Maryhill, running thence easterly by the most feasible route along the north bank of the Columbia river to a point in the vicinity of Plymouth, thence in a northeasterly direction to a junction with Primary State Highway No. 3 in the vicinity of Kennewick.
^Prahl, C. G. (December 1, 1965). "Identification of State Highways"(PDF). Washington State Highway Commission, Department of Highways. Retrieved April 23, 2013.
^The Dalles, 1971(JPG) (Map). 1:250,000. United States Geological Survey. 1971. Retrieved April 23, 2013.