Interstate 82: route, history, and key features of a Pacific Northwest corridor

Route and characteristics

Beginning at a junction with Interstate 90 and U.S. Route 97 in Ellensburg, I‑82 descends southeast into the Yakima Valley, passing the city of Yakima. It continues across irrigated farmland and through river canyons toward the Columbia River basin and the Tri‑Cities area, serving the cities commonly grouped as the Tri‑Cities (Richland, Pasco and Kennewick). East of the Tri‑Cities the highway crosses into Oregon near Umatilla and terminates at an interchange with Interstate 84 near Hermiston. Major functional characteristics include multiple lanes in each direction on busiest segments, long rural stretches with truck traffic, and grade-separated interchanges where it traverses urban areas.

Major junctions and connections

• Western terminus: I‑90 / US‑97 at Ellensburg (Ellensburg).
• Yakima area: regional access to Yakima and agricultural distribution points.
• Tri‑Cities connections: interchange networks serving Richland, Pasco, and Kennewick.
• Eastern terminus: I‑84 near Hermiston after passing Umatilla.
• Spur route: Interstate 182 (I‑182) provides a direct link into Richland and Pasco.

The spur I‑182 is signed and constructed as part of the regional interstate network; it shortens urban travel and improves river crossings compared with routing all traffic on I‑82.

History and numbering oddity

I‑82 was built in stages during the mid‑20th century as part of the Interstate Highway System. A notable historical detail is that I‑82 lies north of I‑84 for part of its route, which appears to contradict the Interstate numbering convention that east–west even numbers increase from south to north. This anomaly resulted from the renumbering of an older route designated I‑80N to I‑84 during a systemwide change around 1980 to eliminate split lettered numbers; the renumbering left I‑82 situated north of the new I‑84 on the map.

Notable structures and engineering

One of I‑82's prominent engineering features is the Fred G. Redmon Bridge near Selah Creek, which spans a deep canyon and provided, at its opening in the early 1970s, one of the longest concrete arch spans in North America. The highway also includes long elevated sections, river crossings and interchanges designed to accommodate heavy truck flows associated with agricultural and industrial commerce.

Uses, importance and proposals

I‑82 carries regional passenger traffic and substantial freight movements between inland distribution centers and the Columbia River corridor. It links orchards, vineyards and processing facilities in the Yakima Valley with rail and river terminals. Over the years there have been proposals to extend or modify portions of the route to improve traffic flow or to provide new connections in Oregon; some proposals have been studied but not constructed. Local authorities periodically evaluate improvements for safety, capacity and maintenance, reflecting the highway's role in regional economic activity.

For deeper technical details, official mileposts and project histories consult state transportation pages and planning documents via the cited resources: route information, I‑90 connection, Ellensburg, Yakima, Tri‑Cities, Umatilla, Hermiston and I‑84, and the spur page for I‑182 serving Richland and Pasco.