| Interstate 581 in Virginia |
Interstate 581 in Virginia is the 6.75-mile-long freeway from I-81 in Roanoke County to downtown City of Roanoke. I-581 serves as an Interstate spur from I-81 to the central business district of the City of Roanoke, and the freeway continues as the 3.54-mile-long Roy Webber Highway (Southwest Expressway) to the VA-419/US-220 junction near the southwest edge of the City of Roanoke. The entire I-581/Webber Highway facility is a limited-access highway and it is co-signed as US-220. The I-581 designation ends in the downtown.
The 5.69-mile-long section of I-581 from I-81 to US-460 Orange Avenue opened in 3 sections from Dec. 21, 1964 to Sept. 14, 1965. The remaining 1.06 miles opened in 2 sections, with the last 0.66 mile to the downtown opening on Oct. 12, 1967. The Southwest Expressway was completed in 1980. The I-581 highway was built with 6 lanes, and there have been no widening projects.
I-581 serves the Roanoke Regional Airport. I-581 and part of I-81 serve as the bypass route for traffic on north-south US-220 which is part of the Arterial System of intra-state highways in Virginia. Arterial US-220 runs from the North Carolina border south of Martinsville to I-64 at Clifton Forge.
VDOT 1997 traffic volume data follows. Figures are published rounded to the nearest 100. Traffic volumes on I-581 near I-81 are 47,000 AADT with 5% large trucks. Volumes increase progressively toward the downtown, reaching 79,000 and 4% large trucks in the downtown. The US-220 freeway between Bus. US-220/VA-419 and Wonju Street carries 30,000 AADT, and between Wonju Street and I-581 the volume is 52,000 AADT; and truck volumes are 15%.