182 km.

Interstate 182 (I-182) is an east–west auxiliary Interstate Highway in the U.S. state of Washington. It serves as a connector from I-82 to the Tri-Cities region that crosses the Columbia River on the Interstate 182 Bridge between Richland and Pasco. I-182 is 15 miles (24 km) long and entirely concurrent with U.S. Route 12 (US 12); it also intersects State Route 240 (SR 240) and US 395.
Business leaders in the Tri-Cities began lobbying for a freeway in 1958 after early alignments for I-82 were routed away from the area. I-182 was created by the federal government in 1969 as a compromise to the routing dispute, which allowed for direct access to the Tri-Cities and a bypass for other traffic. The new freeway would also include construction of a bridge between Richland and Pasco, proposed since the 1940s at the site of an earlier cable ferry that ran until 1931.
Construction on I-182 was scheduled to begin in 1971, but was delayed by opposition from conservation groups, disputes over interchange locations, and a federal freeze on highway funding in 1980. The first section to be built, over the Yakima River west of Richland, began construction in late 1980 and opened to traffic three years later. The Interstate 182 Bridge opened in November 1984 and linked to a longer section opened a month earlier in Pasco connecting to the existing US 12 bypass. The final sections of the freeway, between I-82 and Richland, opened to traffic in March 1986.

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