The two major corridors considered for Interstate 82 were (1) the Umatilla route, beginning at I-84 in Stanfield, Oregon and traveling northwest through Umatilla toward Prosser, Washington or (2) from Interstate 84 at Pendleton, then northwest to Wallula and then northwest to Prosser in Washington. Washington and Oregon disagreed on which cities would be served by the proposed route of I-82. The states of Washington and Oregon however did not agree on where to build the freeway, and the alignment of I-82 would remain incomplete and undergo several corridor studies. I-82 was an original route included in the Interstate Highway System by the federal Secretary of Commerce in 1956, based on a Department of Defense recommendation. Known as McNary Highway Number 70 in Oregon, Interstate 82 stays to the west through agricultural areas outside Herimiston to end at I-84 adjacent to Umatilla Army Depot. 395 breaks away from the freeway at Umatilla just south of the state line to combine with U.S. The bridge consists of separate spans the eastbound crossing opened in 1955 and the westbound was completed in 1987. Once at Plymouth, the two meet the east end of Washington Route 14 and the Columbia River. The pair depart the Tri-Cities for a southerly route over Horse Heaven Hills along side Bofer and Fourmile Canyons. Staying south of Badger Mountain along the periphery of Horse Heaven Hills, Interstate 82 bypasses Kennewick to the merge with U.S.

12 separates with I-82 for Interstate 182, a freeway spur leading east through Goose Gap to Richland and Pasco. 12 remain paired through eastern reaches of Yakima Valley to Grandview and Prosser before ascending along the northern slopes of Horse Heaven Hills east to Benton City and the Tri-Cities area. 12 shift southeast along the Yakima River toward Snipes Mountain and Sunnyside. 97 parts ways with the corridor for Wapato and Toppenish while I-82/U.S. 12 and 97 through eastern reaches of the city adjacent to the river. Yakima used to include a Business Loop for I-82 through Downtown, while I-82 combines with U.S.

Highway 82 washington