List of gaps in Interstate Highways
For the most part, the Interstate Highway System in the United States is a connected system, with most roads completed; however, some Interstates still have gaps. This is a list of gaps in the Interstate Highway system where the roadway carrying an Interstate shield does not conform to the standards set by the Federal Highway Administration (FHWA), the body that sets the regulations for the Interstate Highway System. These gaps can be due to an unintended disconnection between two segments of the same route, failure of the roadway to be a full freeway, usage of traffic signals, or movable bridges (lift bridges and drawbridges). This article deals with present day gaps, not the rampant examples of gaps when the Interstate Highway System was in its infancy since gaps were more expected back then. Temporary gaps, such as lane closures that reduce traffic to one lane in each direction with a reduced speed limit for a short distance from reconstruction, are also excluded.
True gaps
True gaps are where two sections of road are intended to be part of the same Interstate, but the two sections are not physically connected, are only connected by non-Interstates, or are connected but the connection is not signed as part of the highway.
- Interstate 69 has four sections: the original alignment runs from Indianapolis, Indiana, to Port Huron, Michigan. On October 2, 2006, a segment of I-69 opened in Tunica and DeSoto counties in Mississippi. Another section exists near Evansville, Indiana. This section, however, is expected to be connected to the original I-69 in Indianapolis in 2016. In December 2011, a section southwest of Corpus Christi, Texas opened, as well.
- Interstate 73 has two sections: a section of the Greensboro Urban Loop in Greensboro, North Carolina, the only section of I-73 signed with normal Interstate shields,[1] and one concurrent with the entire section of I-74 from Ulah to Ellerbe, North Carolina.[2] Other sections up to freeway standards are signed with I-73 shields that have FUTURE instead of INTERSTATE.
- Interstate 74 currently has five sections,[3] one heading west from Cincinnati, Ohio, to Davenport, Iowa; one from the Virginia/North Carolina line along Interstate 77 south/east to a point southeast of Mount Airy, North Carolina; one running concurrent with US 311 around High Point connecting with I-85; one concurrent with the entire section of I-73 from Ulah to Ellerbe, North Carolina; and from west of Laurinburg to south of Lumberton, North Carolina, at Interstate 95. Other sections up to freeway standards are signed with I-74 shields that have FUTURE instead of INTERSTATE. Future I-73 shields are also placed along some of these sections. North Carolina is currently working on connecting all its sections of I-74, though the gap to Cincinnati will remain for the foreseen future.
- The eastern Interstate 86 currently has three sections. One runs from I-90 in North East, Pennsylvania, to Exit 56 in Elmira, New York. The second section is a 9.9-mile (15.9 km) stretch outside of Binghamton running from I-81 in Kirkwood to exit 79 in Windsor. In 2009, a third section opened near Middletown, New York. I-86 will eventually run from North East, Pennsylvania, to Harriman, New York, connecting to I-87. All the designated sections and gaps are a part of the NY 17 expressway.
- Interstate 95. Probably the best-known and most notoriously confusing of all the Interstate gaps, I-95 is discontinuous in Lawrence Township, New Jersey (near Trenton). Coming north from Philadelphia, Pennsylvania, I-95 loops around the north side of Trenton and ends at U.S. Route 1, where it becomes I-295, which heads back south, heading to southern New Jersey. The other section of I-95 begins on the Pennsylvania Turnpike at the Pennsylvania/New Jersey state line, heads east into New Jersey along a spur of the New Jersey Turnpike, then heads north along the New Jersey Turnpike mainline. Originally I-95 was planned to have left the alignment north of Trenton and headed northeast to Interstate 287 and run east along I-287 to Exit 10 on the Turnpike, but the Somerset Freeway was never built. Extensions over the years have taken I-95 several miles further north to the US-1 interchange northeast of Trenton, and along the New Jersey Turnpike to the Pennsylvania state line. An interchange is under construction, connecting the southern alignment with the Pennsylvania Turnpike, and I-95 will be rerouted via it, with the part north of that interchange becoming an extension of I-195.[4] (It was originally considered to be an extension of I-295.)
Disputed gaps
Gaps where different criteria constitute contradictory circumstances.
- I-90 at the Chicago Skyway — Historically, the Skyway was commonly considered to be, and was signed as, part of I-90 (originally I-94). However, around 1999, the City of Chicago, Illinois, determined it may never have applied for approval to sign it as an Interstate. (It also is not designed to Interstate standards.) The city re-signed the Skyway, and it is now mostly posted with "TO I-90" signs with a few older signs remaining. However, the Illinois Department of Transportation has always and continues to report the Skyway as part of the Interstate system, and the Federal Highway Administration still considers it as such. A FHWA legal memo says "There is no doubt about it. The Chicago Skyway is officially part of I-90 that (has) always been included in the Dwight D. Eisenhower National System of Interstate and Defense Highways."[5][6]
- I-265. The Indiana portion of I-265 does not yet connect with the Kentucky portion of I-265. Each of the two segments, circling the outskirts and suburbs of Louisville, ends before crossing the Ohio River, making them completely in separate states. Plans for constructing a bridge to connect the two segments have been finalized, though the project is far from complete.[7]
Freeway gaps
Freeway gaps occur where the Interstate is signed as a continuous route, but part or all of it is not up to freeway standards. This includes drawbridges where traffic on the Interstate can be stopped for vessels. This does not include facilities such as tollbooths, toll plazas, agricultural inspection stations, or border stations.
At-grade intersections and traffic lights
Several Interstates in rural areas of the U.S. have at-grade intersections (including median breaks) with minor farm access roads. This is usually due to the lack of an old highway; the need to provide access to property that was accessed via the road prior to upgrade to Interstate; and the high cost to construct an interchange for the small amount of traffic that would use such a connection or to build a frontage road parallel to the freeway to the nearest interchange.
- I-70 uses part of US 30 along a surface road in Breezewood, Pennsylvania, to get between the freeway heading south to Hancock, Maryland, and the ramp to the Pennsylvania Turnpike. This is probably the best-known instance of traffic lights on an interstate. There used to be a sign of a policeman pointing at drivers leaving the Pennsylvania Turnpike to enter US 30, saying, "You! Slow Down!" Local businesses have lobbied to keep the gap to avoid loss of business (Map).[8]
- I-78 travels along a one-way pair of surface streets, 12th Street and 14th Street, in Jersey City, New Jersey, between the end of the New Jersey Turnpike Newark Bay Extension and the Holland Tunnel, which leads into New York City. Between the two aforementioned points are four signalized intersections.[9]
- I-180 in Cheyenne, Wyoming, has no parts built to Interstate standard; in fact the interchange with I-80 is just a simple diamond interchange with two traffic lights on I-180, however it is expressway-quality with a few grade-separations (Map).
- I-585 in Spartanburg, South Carolina, is cosigned with US 176, in which I-585 shields are present in beyond the point where it ceases to be a freeway, having passed through traffic lights. There also exists a sign that marks the road there as "I-585 Business Spur" and hence it is unclear whether that surface section of US 176 also belongs to I-585.
- I-676 has a surface street section at the west end of the Ben Franklin Bridge in Philadelphia, Pennsylvania, because of historically significant areas. Signage and the Federal Highway Administration consider I-676 to use the surface streets; the Pennsylvania Department of Transportation and the New Jersey Department of Transportation consider I-676 to be continuous across the Ben Franklin Bridge, even though the bridge, built in 1926, is not up to Interstate standards (Aerial photo).
- I-690 in Syracuse, New York, has a traffic light 12 days each year for buses to carry Great New York State Fair attendees from parking areas across the road to the fair.
- Several at-grade access points exist for cattle ranches along I-35 in the Flint Hills in Kansas, and for cattle ranches along I-10 and I-40 in remote areas of West Texas.
Undivided and narrow freeways
This section addresses two-lane freeways and other narrow or undivided freeway sections of the Interstate, excepting instances of continuing routes using one-lane ramps and merge leads.
- Interstate 93 is a two-lane, divided parkway, or a super-two, through Franconia Notch in New Hampshire. A four-lane Interstate Highway was once proposed here, but the concept was abandoned because of environmental concerns, in part because of vibrations that could harm the Old Man of the Mountain rock formation, prior to the formation's 2003 collapse. This section of highway was for many years marked as U.S. Route 3 and "To I-93", but these have now been replaced with regular Interstate 93 signs. The Federal Highway Act of 1973 exempts this stretch from the Interstate Highway standards that apply elsewhere, and this highway is considered to be I-93 for all practical purposes.[10]
- Some stretches of Interstate highway use a barrier transfer machine on some bridges where it would be too costly to upgrade/rebuild to a higher-capacity bridge. In any case the traffic distribution is strongly asymmetric depending on the hour of the day. This kind of bridge typically contains undivided lanes without the flexible Jersey barrier that is manipulated by machines.
Movable bridges
By Interstate standard, all bridges on the Interstate system must be fixed as to not interrupt the flow of traffic. Several bridges on the system, however, are movable:
- Interstate 95 and Interstate 495 pass together as the Capital Beltway over the Potomac River on the Woodrow Wilson Bridge, a double-leaf bascule span. Even though the original bridge was replaced in the 2000s, the new bridge also has a draw span, albeit with more vertical clearance resulting in fewer openings than the old bridge — about 65 per annum, an average of about one every six days.
Other movable bridges on the Interstate System have been replaced after spending many years as part of the system. These include:
- Interstate 75 (Michigan) had a bascule bridge from 1960 to 1988 at Zilwaukee, just north of Saginaw; the high-level Zilwaukee Bridge replaced it on December 23, 1987, for northbound traffic, and on September 19, 1988, for southbound traffic.[14] Interstate 675 was built as an in-town bypass of the bascule bridge prior to the construction of the tall Zilwaukee bridge. Since the completion of the tall Zilwaukee bridge in 1987, I-675 has had less traffic than its capacity; though it is a feasible detour for bridge, or other maintenance between both ends of the loop.
Connection gaps
Auxiliary Interstates (also known as 3-digit Interstates) are intended to connect to their parent either directly or via a same-parented Interstate (like I-280 in California being connected to I-80 via I-680). Often, these connection gaps occur to eliminate concurrencies between other 3-digit routes.
- Interstate 210 in California does not connect directly to Interstate 10, although I-210 is continuous with California State Route 210, which does connect to I-10, and California is petitioning to have that portion signed as Interstate 210 also. When that happens, this gap will disappear. I-210 does not connect to any of the spurs of I-10, with the exception of a short, unsigned, unfinished section of Interstate 710 which connects to State Route 110 only via surface streets.
- None of the spurs of I-78 (I-278, I-478, I-678, I-878) connect to its parent. I-78 was planned to extend through New York City and end as two branches, where I-295 and I-695 now end at I-95. I-478 comes the closest, and would have intersected if the Westway project were not canceled; I-278, the only I-78 spur to leave New York City, was planned to extend northwest to I-78 at Route 24. Since all the spurs are interconnected, only one of them needs to be eventually connected to its parent route for all of them to conform to standards.
- Freeway gaps (signed or unsigned) that officially connect auxiliary routes to the parent are excluded.
- I-585 used to connect with I-85 in Spartanburg, South Carolina, but I-85 was moved to a new bypassing route, and now I-585 ends at the I-85 Business loop. The signed connection to I-85 is via a surface section of US 176.
Instances of triple digit designations that cross state lines when they connect to the Interstate in the neighboring state but do not reconnect in that state are excluded from this list. But there are even instances of triple-digit interstates that cross state borders into states where their parent does not even exist. However, Interstate 238 in the San Francisco area is an example of a triple-digit Interstate whose parent doesn't exist at all, on a side note: Every I-x80 designation in the San Francisco area was taken at the time I-238 was commissioned, in which an instance of a California state route with an x80 designation eliminated a candidate for a 3-digit Interstate designation as California law prohibits state highways from having common numbers with co-existing US and Interstate highways.
Examples of these connection gaps are subject to dispute with unofficial, unsigned concurrencies with other routes to the parent.
Other gaps
- In four cases — I-76, I-84, I-86 and I-88 — the same primary interstate route number is used on two separate, unconnected lengths of roadway, one in the eastern portion of the country and one in the western portion. These gaps are intentional — the two segments of roadway are not planned to be linked together.
References
- ^ "I-73 Segment 4". http://www.duke.edu/~rmalme/i73seg4.html. Retrieved 2009-11-19.
- ^ "I-73 Segment 9/I-74 Segment 10". http://www.duke.edu/~rmalme/i73seg9.html. Retrieved 2009-11-19.
- ^ Bob Malme. "I-74 North Carolina Progress Page". Duke.edu. http://www.duke.edu/~rmalme/prog74.html. Retrieved 2009-08-28.
- ^ Rose, Joel. "At Last, I-95's Missing Link Hits The Road". NPR, 2010-08-21.
- ^ "Tolling and Pricing Program - FHWA Operations". Fhwa.dot.gov. http://www.fhwa.dot.gov/programadmin/toll_Rds.html. Retrieved 2009-08-28.
- ^ http://tollroadsnews.info/artman/publish/article_969.shtml
- ^ "Kentucky Indiana Bridges - Home". Kyinbridges.com. http://www.kyinbridges.com/. Retrieved 2009-08-28.
- ^ Manuel Roig-Franzia, "The Town That Stops Traffic: Travelers Encounter Way Station as Way of Life in Breezewood," Washington Post, 22 November 2001, B1.
- ^ "Intersection of 14th St (ostensibly 78 West) and Erie St". Maps.google.com. 1970-01-01. http://maps.google.com/maps?q=Jersey+City+NJ&t=h&ie=UTF8&ll=40.731861,-74.042729&spn=0.001785,0.004828&z=18&layer=c&cbll=40.731839,-74.042516&panoid=5dvrrt9-DUeW4FQkik1ltg&cbp=12,273.3558391375674,,0,3.999999999999998. Retrieved 2009-08-28.
- ^ "Interstate System Conditions and Performance - Highway History - Infrastructure - FHWA". Fhwa.dot.gov. http://www.fhwa.dot.gov/infrastructure/intrstat.cfm. Retrieved 2009-08-28.
- ^ "Home". Columbia River Crossing. http://www.columbiarivercrossing.org/. Retrieved 2009-08-28.
- ^ Maryland State Highway Administration (2007). "Highway Location Reference: Anne Arundel County" (PDF). http://apps.roads.maryland.gov/KeepingCurrent/performTrafficStudies/dataAndStats/hwyLocationRef/2007_hlr_all/co02.pdf. Retrieved 2009-04-15.
- ^ Maryland State Highway Administration (2010). "Movable Bridges on State Maintained Highways" (PDF). http://www.sha.maryland.gov/OBD/movablebridges.pdf. Retrieved 2010-10-18.
- ^ "In Depth: The Zilwaukee Bridge". http://www.michiganhighways.org/indepth/zilwaukee.html. Retrieved 2011-01-30.
External links