Interstate 40 (I-40) is an Interstate Highway in Oklahoma that runs 331 miles (530 km) across the state from Texas to Arkansas. West of Oklahoma City, it parallels and replaces Old US-66, and east of Oklahoma City, it parallels US-62, US-266 and US-64.
Cities along the route include Erick, Sayre, Elk City, Clinton, Weatherford, El Reno, Oklahoma City, Shawnee, Okemah, Henryetta, Checotah and Sallisaw.
Interstate 40 enters Oklahoma near Texola, in Beckham County. It crosses the North Fork of the Red River near Sayre and runs through the south side of Elk City. It then cuts across the northwest corner of Washita County before entering Custer County, where it passes through Clinton and Weatherford. After leaving Weatherford, I-40 then runs across the northern tip of Caddo County before it enters Canadian County.
I-40 runs through the south side of El Reno, entering the Oklahoma City metro. It then passes through Yukon before entering Oklahoma City proper. There, it has a junction with Interstate 44 (the Amarillo Junction). It then runs just south of downtown Oklahoma City on an elevated, dilapidated structure called the I-40 Crosstown, which is scheduled for replacement in 2012. It next meets Interstate 35 in the Fort Smith Junction complex, forming a concurrency with it for about two miles (3 km). It then passes through Del City and Midwest City on a freeway known as the Tinker Diagonal, providing access to Tinker Air Force Base in Oklahoma City.
In far eastern Oklahoma City, I-40 meets Interstate 240 in a partial junction before passing through the north side of Shawnee. In Henryetta, I-40 serves as the northern terminus of the Indian Nation Turnpike. In McIntosh County, it crosses the northernmost arm of Lake Eufaula and meets the US-69 freeway south of Checotah.
Near Webbers Falls, I-40 is the southern terminus of the Muskogee Turnpike. It then crosses the Arkansas River before heading around southern Sallisaw. The interstate crosses into Arkansas north of Moffett.
West of Oklahoma City, Interstate 40 parallels and replaces Old US-66. US-66 was decommissioned in Oklahoma in 1985.
The I-40 bridge over the Arkansas River/McClellan-Kerr Navigation System near Webbers Falls was struck by a barge on May 26, 2002, causing the bridge to collapse and resulting in the death of 14 people.
Oklahoma City Crosstown realignment
The I-40 Oklahoma City Crosstown Expressway was built in 1966; however, this stretch of elevated highway is too narrow for existing traffic, and is in disrepair. In response, I-40 is being relocated a few blocks south of the exiting route, with the current elevated route torn down, and a landscaped boulevard built on the old right-of-way, similar to the I-30 reconstruction through downtown Fort Worth, Texas. The project was completed in February 2012.
Business routes and old alignments
I-40 has eight business routes in Oklahoma, six of which are old alignments of US-66. A number of other old alignments of US-66 are also present west of Oklahoma City.
Erick I-40 Business Loop (formerly US-66) is a Business Loop that runs from I-40 two miles (3 km) west of Erick to the old alignment of US-66, through Erick, and back to I-40, four miles (6 km) east of Erick.
Sayre I-40 Business Loop (formerly US-66) is a Business Loop that begins two miles (3 km) south of Sayre at US-283, runs north into the city, and then leaves Sayre to the east, rejoining I-40 two miles (3 km) east of US-283.
Elk City I-40 Business Loop (formerly US-66) is a Business Loop that begins at Exit 32, seven miles (11 km) west of Elk City. It runs for ten miles (16 km) through Elk City, rejoining I-40 at Exit 41.
Clinton I-40 Business Loop (formerly US-66) is a Business Loop that begins at Exit 65, runs five miles (8 km) through Clinton, and rejoinds I-40 at Exit 69.
Weatherford I-40 Business Loop (formerly US-66) is a Business Loop that exits I-40 at Exit 82B, runs four miles (6 km) through Weatherford, and rejoins I-40 at Exit 82.
El Reno I-40 Business Loop (formerly US-66) is a Business Loop through El Reno. It exits I-40 at Exit 119, runs eight miles (13 km) through El Reno, and rejoins I-40 at Exit 125, the interchange with US-81.
Henryetta I-40 Business Loop (formerly US-62/US-75) is a Business Loop that leaves I-40 at Exit 237, runs four miles (6 km) through Henryetta, and rejoins I-40 at Exit 240, the interchange with US-75 and the Indian Nation Turnpike.
Sallisaw I-40 Business Loop is a Business Loop that leaves I-40 at Exit 308, US-59, runs four miles (6 km) through Sallisaw, and rejoins I-40 at Exit 311, US-64.