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Paper Highways: The Unbuilt New Orleans Bypass (Proposed I-410)


There are many examples around the United States of proposed freeway corridors in urban areas that never saw the light of day for one reason or another. They all fall somewhere in between the little-known and the infamous and from the mundane to the spectacular. One of the more obscure and interesting examples of such a project is the short-lived idea to construct a southern beltway for the New Orleans metropolitan area in the 1960s and 70s. Greater New Orleans and its surrounding area grew rapidly in the years after World War II, as suburban sprawl encroached on the historically rural downriver parishes around the city. In response to the development of the region’s Westbank and the emergence of communities in St. Charles and St. John the Baptist Parishes as viable suburban communities during this period, regional planners began to consider concepts for new infrastructure projects to serve this growing population. 

The idea for a circular freeway around the southern perimeter of the metro gradually came together in the 1960s as a combination of five separate projects, including plans for two new Mississippi River Bridges, one each at the eastern and western fringes of the metro, an east-west “relief route” for the Westbank Expressway in southern Jefferson Parish known as the “Dixie Freeway”, and a freeway upgrade to the Paris Road corridor in St. Bernard Parish and New Orleans East. These separate projects were coalesced by planners into a much larger single continuous freeway, but initially lacked the funding necessary for such a large-scale effort. Opportunity arose in the late 1960s when provisions in the Federal Aid Highway Act of 1968 enabled a 1,500-mile expansion of the interstate system nationwide. The southern bypass, the entirety of it now colloquially known as the Dixie Freeway, was added into the interstate system as part of this expansion later that year. Additional interstate mileage for Louisiana was made available the following year a upon the cancellation of the Vieux Carre Riverfront Expressway through downtown New Orleans, which had been proposed as I-310. By 1972, with federal funding for the project secured under the interstate highway program, the southern bypass was designated as proposed Interstate 410, a 48-mile loop connecting to Interstate 10 both in St Charles Parish to the west and New Orleans East on the other side of the city.

This c. 1972 map provided by "" shows the proposed alignment of the southern New Orleans Bypass, known as the "Dixie Freeway" and intended to be signed as Interstate 410. The Hale Boggs Memorial Bridge was planned as the western of the two new Mississippi River bridges intended as part of the plan. A second bridge would have crossed the Mississippi downriver from downtown New Orleans near Chalmette.

The exact path the freeway would have taken was never clearly defined. Various alignments were studied during the early 1970s and while a preferred alignment was identified around this time, nothing definitive enough emerged that enabled engineers to begin final design work along the length of project. Heading east from the present southern terminus of Interstate 310, it’s likely that the highway would have turned east to parallel the US Highway 90 corridor to the south. After crossing the wetlands around Lake Cataouatche and Bayou Segnette, perhaps on a series of elevated causeways like the I-55 bridges across the Manchac Swamp west of New Orleans, the freeway may have roughly paralleled Lapalco Boulevard and the Gulf Intracoastal Waterway as it crossed the Westbank suburbs in southern Jefferson Parish. A new Mississippi River bridge would have been constructed somewhere in the vicinity of lower Algiers in southeastern Orleans Parish and Chalmette in St. Bernard Parish. Since a final location was never determined, no final renderings for this bridge were produced. It is likely that this bridge would have taken the form of a high-rise steel truss bridge similar in appearance to bridges such as the nearby Crescent City Connection or the Veterans Memorial Bridge in Gramercy. Once in St. Bernard Parish, the freeway would have roughly paralleled Paris Road (LA Highway 47) as it crossed additional wetlands north and east of Chalmette, again likely on lengthy elevated causeway structures common to southern Louisiana. A high-rise bridge, known locally as the “Green Bridge”, was built over the Gulf Intracoastal Waterway and the Mississippi River Gulf Outlet and opened in 1967. This bridge, which carries Paris Road (LA 47) today, would have been included as part of this highway.

The Hale Boggs Memorial Bridge was completed in 1983 and was originally part of the proposed Interstate 410 corridor. Today it is part of I-310.

Despite the clear interest in the project at the local, state, and federal level, momentum for building the highway stalled shortly thereafter. Concerns over the projected extreme costs associated with building a freeway mostly on elevated viaducts and causeways across the combination of swamps and suburbia proved to be too daunting a vision for everyone to agree on. Other factors riding against the highway’s construction were the rise of the environmental conservation movement in the 1970s, the creation of the Environmental Protection Agency (EPA), and changes to federal laws that placed highway projects in areas near sensitive wetlands under greater scrutiny. Environmentalist groups across the region threatened legal action against the project, with the aim of indefinitely postponing construction across the wetlands of Jefferson and St. Bernard Parishes. As a result of the growing environmental opposition to the project, as well as the lack of a clear path forward in terms of a physical right-of-way for the freeway, FHWA approved Louisiana’s written request to remove the I-410 designation from its roster in January 1977. The request included a provision that left open the possibility for the eastern & westernmost fringes of the proposed loop to be built as separate projects at a later date and these areas retained their interstate system status as a result, though both would be renumbered in the ensuing years.

Final design for the proposed Algiers-Chalmette Bridge downriver from downtown New Orleans never took place so it's not known what the bridge would have looked like. One possibility is that it would have been modeled in a fashion similar to the Veterans Memorial Bridge in Gramercy, LA.

Following the cancellation of the southern bypass, both these eastern & westernmost legs of the corridor remained active proposals into the 1980s and both eventually were constructed mainly as planned. The western leg, which connects Interstate 10 with US Highway 90 in Boutte was completed in 1993 and is signed as Interstate 310, the second iteration of the designation in the state of Louisiana. The eastern leg, which connects Interstate 10 with the Paris Road Bridge and St. Bernard Parish was completed in 1992 and is signed as Interstate 510. The central 34 miles of the unbuilt I-410 between Boutte and New Orleans East were traded in and utilized for the new I-49 corridor between Lafayette and Shreveport, construction of which began in the 1980s and was completed in 1996.

This c. 1972 map (overlaid with highlights by show the various studied alignments of the proposed I-410 bypass across the Westbank of New Orleans. A preferred alignment was identified (labelled in bright green), however the project did not advance to final design.

The Unbuilt Bridges of the Mississippi River were featured in the "Bridges of the Lower Mississippi River" webinar on the 'roadwaywiz' YouTube channel, beginning at the 2:40:00 mark:

Further Reading & Sources:


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