Existed: October 1998 – present Constructed October 1998 | Length 37.5 km | |
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South end: I-255 / I-270 in Pontoon Beach |
Illinois Route 255 (IL 255), also referred to as the Alton Bypass, is a northwesterly extension of Interstate 255 (I-255) in southwestern Illinois. IL 255 starts at I-270 in Pontoon Beach and ends at U.S. Route 67 (US 67) north of Godfrey near its junction with IL 267 and IL 111, at a total length of approximately 23.3 miles (37.5 km).
Contents
Map of IL-255, Illinois, USA
Route description
IL 255 is a four-lane, limited-access freeway for its entire length. It serves as an important circumferential artery for the northeastern portion of the St. Louis, Missouri, metropolitan area. The final segment was completed on November 23, 2012, and runs 4.3 miles (6.9 km) from Seminary Road to US 67 north of Godfrey near its junction with IL 267 and IL 111. The highway passes just to the west of the St. Louis Regional Airport.
Although IL 255 was designed to federal Interstate Highway standards, it was built by the Illinois Department of Transportation (IDOT) using state-provided funds.
History
Described as "the Road to Prosperity" by business leaders and government officials who initially proposed it in the late 1970s, IL 255 was part of a region-wide effort to create a high-speed alternative to US 67 over the Clark Bridge through the city-center of Alton, and to two congested local routes (IL 3 and IL 111) that roughly parallel the IL 255 corridor. Although it was part of the much larger Corridor 413 plan, the local politicians focused mostly on the segment from I-270 to what was then IL 267 north of the Godfrey "Y" intersection. At that time, the Berm Highway, the Beltline extension, and the Madison Avenue connector were not built and both IL 3 and IL 111 were over capacity between Alton and I-270. In 1975, a six-month detour related with the closing of the Old Clark Bridge exposed the need for the Alton Bypass along with the other three routes. However, until 1985, the Alton Bypass was a low priority, as other local road projects in the area were considered more important.
The first 6.5-mile (10.5 km) segment of IL 255, from I-270 to IL 143, was completed in October 1998 at the cost of $40 million (excluding land acquisition).
The second segment, a 7.2-mile (11.6 km) extension from IL 143 in Roxana to Fosterburg Road, was opened on October 20, 2006, approximately one year behind schedule, owing to the 2005 collapse of the Wisconsin-based construction company that held the contracts for that portion of the roadway. The second segment was completed at a cost of approximately $78.1 million.
The third segment of IL 255 from Fosterburg Road to Seminary Road in rural northeast Alton opened on August 22, 2008. Construction costs for this portion of the roadway totaled $25.1 million.
The fourth and penultimate segment of the highway from Seminary Road in Alton to Humbert Road in Godfrey opened on October 26, 2012.
The fifth and final segment of the highway runs 4.3 miles (6.9 km) from Seminary Road to US 67 north of Godfrey near its junction with IL 267 and IL 111 at a cost of $22 million.
Future
Now complete, the IL 255 route may or may not be redesignated as an Interstate Highway. If the corridor were to be signed as an extension of the current I-255 bypass, all exits north of I-270 would have to be renumbered. As a standalone spur route, IL 255 numbered as I-255 would violate the American Association of State Highway and Transportation Officials scheme for Interstate numbering that requires an odd-number first digit (although as part of the larger I-255 bypass the route is not technically a spur even though it extends past the segment of I-55 that it bypasses). The entire corridor from Godfrey to Mehlville, Missouri, comprising both I-255 and IL 255 could also carry secondary signage as US 67 Bypass, since it would be a true bypass of US 67, which passes through the St. Louis urban agglomeration, actually connecting with US 67 at both endpoints.
Construction of a new expressway route for US 67 between Jacksonville and Alton is planned to follow the corridor through White Hall, Carrollton, and Jerseyville. It will end in Godfrey near the IL 255 extension.
Exit list
The entire route is in Madison County.