Special route
In
Nomenclature
In the field, the special route is typically distinguished from the parent route with the use of auxiliary words or suffix letters placed on the route shield or on an adjacent sign, known as a "banner" or "plate" or according to the
The
Some old alignments of routes may also be informally known as special routes (despite some that do not intersect the parent route). These older alignments may be given street names like "Old U.S. Highway 52", or in some rare cases, be signed with route shields attached to "Old" or "Historic" sign plates (such as decommissioned sections of former U.S. Route 66 that are still driveable).
In the case of U.S.
A few highways have two special route designations. Some of these doubly designated special routes are:
- Alternate Business US 66 in Springfield, Missouri
- Business US 1A in downtown Bangor, Maine
- Truck Business US 17 in Elizabeth City, North Carolina
- Business US 77 Alternate in Yoakum, Texas
- U.S. Route 202 Alternate Truck in Montgomery County, Pennsylvania(Many Pennsylvania highways use this "Alternate Truck" pattern)
- Business Alternate US 58 in Norton, Virginia and Big Stone Gap, Virginia.
There is also an example of a route with three special route designations.
Special route types and respective behavior
Routes with special designations in the U.S. have typical behavior that distinguishes them from other routes. There are, however, many exceptions to the common behavior, depending on the situation.
Business, City, and Bypass routes
Business routes (also known as city routes) can be loops or spurs and generally traverse through or near population centers (usually towns and small cities). They are usually signed with "business" or "bus" auxiliaries or a "B" suffix. Most business routes are the former alignments of their parent. Bypass routes (rarely known as "Relief routes") typically go around population centers and are newer and faster than their mainline and/or business route counterparts.
In some cases, due to
The American Association of State Highway and Transportation Officials (AASHTO) defines a business route for U.S. highways as
...a route principally within the corporate limits of a city which provides the traveling public an opportunity to travel through that city, passing through the business part of the city; while the regular number is used to obviate passing through the congested part of the city. This "Business Route" connects with the regular numbered route at the opposite side of the city limits.[5]
AASHTO defines bypass or relief routes for U.S. highways as:
...a route which is established for the purpose of designating a route which entirely by-passes a city or congested area and joins in with the regular numbered route beyond the city or congested area.[5]
Business Interstates
AASHTO defines a category of special routes separate from primary and auxiliary Interstate designations known as Interstate Business routes. These routes do not have to comply to Interstate construction standards, but are routes that may be identified and approved by the association. The same route marking policy applies to both U.S. Numbered Highways and Interstate highways; however, business route designations are sometimes used for Interstate highways.[6]
Known as
Truck routes
Truck routes were initially known as Bypass routes, and were loops created as a means to divert through truck traffic away from population centers, but the designation was changed to "bypass" in 1959-1960 by AASHTO. Today, Truck routes exist as alternatives for the mainline routes that are ill-suited for large truck travel[7] with obstacles (such as low clearance bridges, sharp turns, or steep grades) or with conditions that could create dangerous situations to smaller vehicles. An example of such a route is U.S. Route 1/9 Truck in New Jersey, which bypasses the segment of U.S. Route 1/9 that uses the Pulaski Skyway, on which trucks are banned.[8]
Alternate Truck Routes
There are alternate truck routes in several counties in southeastern Pennsylvania. They bypass weight-restricted bridges over creeks and rivers. They are mainly routed on major highways and freeways and other roads they intersect to bypass that specific bridge. An example of an alternate truck route is Pennsylvania Route 82 Alternate Truck which bypasses a weight-restricted bridge over East Branch of Red Clay Creek. Most of the alternate truck routes were signed in 2013, though some were signed as recently as 2023.
Alternate and Optional routes
Alternate routes are loops that provide alternative alignment for a parent route. They are usually signed with an "alternate" or "alt" auxiliary or an "A" suffix. They generally traverse through a different settlements or different city neighborhoods than the parent route, but roughly remain parallel to the parent. Unlike business routes and bypasses, their relationship to population centers varies from case to case. Alternates also can be quite longer than most other special routes with some spanning over 50 miles (e.g.
Prior to 1960 there were
AASHTO defines and specifies that alternate routes should have the following behavior:
An "Alternate Route" shall be considered a route which starts at a point where it branches off from the main numbered route, may pass through certain cities and towns, and then connect back with the regular route some miles distant. Since it is the purpose of the U.S. numbered system to mark the best and shortest route available, an alternate route should be designated only where both routes are needed to accommodate the traffic demand, and when the alternate route has substantially the same geometric and structural design standards of the main marked routing. It is recommended that in case an alternate route is marked, that the shorter and better constructed route be given the regular number and the other section designated as the "Alternate Route". It is further recommended that the Highway Department erect signs at the junction points of the regular and alternate routes giving the distance between the cities or points concerned... In no instance should an alternate routing be used for the purpose of keeping an obsolete section on the U.S. numbered system after a new routing has been constructed and available to traffic.[5]
Spur and Connector routes
Spur routes split away from the parent route without returning. They usually end in a settlement or area not served by the parent. Connector routes are spurs that connect the parent route with a nearby prominent route, usually an Interstate highway (e.g.
Scenic routes
Scenic routes, in terms of special routes, are loops of a parent route that traverse through an area of natural or historical significance. Only one route in the country remains with the official Scenic designation: US 40 Scenic.
Toll routes
Toll routes, in terms of special routes, are loops that are faster than the parent route, but are tolled. The other usage with the promulgation of the 2009 MUTCD is to use a new yellow toll plate above the marker along tolled segments of highways.[9]
Loop routes
Loop routes, in terms of special routes, are loops that form a complete radial around an area, having at least one intersection with the parent route. Because of their circumferential nature,
Temporary routes
Temporary routes complete a gap between two segments of a parent route that exists because the parent route through the area has not been fully constructed. They serve as a long-term detour until the parent route's planned path is completed, at which point the Temporary designation is either removed or replaced by another designation such as Alternate or Business. Temporary routes generally traverse along roads of a lower standard than the planned mainline. An example is US 191 through a copper mine north of Clifton, Arizona.
AASHTO defines and specifies that temporary routes should have the following behavior:
In the erection of signs for numbering routes, it is necessary in some cases to carry a number temporarily over a road that ultimately will not be the permanent location of that number. Great care should be taken by the State Highway Departments in seeing that when numbers of this character are permitted, that a standard strip carrying the words "Temporary" shall be placed on the staff above the number. This will obviate much hard feeling when it is necessary to change a number to the permanently established route. [5]
Emergency detour routes
A rare type of special route, known as the Emergency Detour route, is signed with an auxiliary "Emergency" banner that is colored orange, indicating a temporary traffic control sign. The purpose of these routes is to offer an alternative in case the parent route is impassable, due to either a
Ontario, Canada is one jurisdiction outside the United States with a very prevalent system of these roads.
Other governments have a variation on this concept, though not always a "special route":
Divided routes
Some
They are usually loops, but some have been spurs, though since they use directional letter suffixes, they are not generally considered "bannered routes". The American Association of State Highway and Transportation Officials no longer assigns these numbers, and in theory current ones are to be eliminated "as rapidly as the State Highway Department and the Standing Committee on Highways can reach agreement". This policy was adopted by 1996; however, many of these routes still exist, mostly in Tennessee.
History
Originally in the United States, the terms used for special routes were "City", "Truck", and "Optional". In 1959–1960, the terms were changed to "Business", "Bypass", and "Alternate", respectively; however, the "Truck" banner is still used today on many routes, especially those where trucks are prohibited on the mainline (for example, U.S. Route 1/9 Truck in Jersey City, New Jersey, which routes trucks around the Pulaski Skyway, which bans them). The American Association of State Highway and Transportation Officials (AASHTO) has called for the removal of "alternate" routes, though many still exist.
See also
- List of auxiliary Interstate Highways
- List of special routes of the United States Numbered Highway System
- List of business routes of the Interstate Highway System
References
- )
- ^ Kinsler, Wes (April 15, 2004). "Oklahoma's U.S. Highway History". Retrieved October 1, 2014.[self-published source]
- ^ Voss, Oscar (December 2010). "FAQ Page 3". Hawaii Highways. Retrieved October 1, 2014.[self-published source]
- ^ Staff. "500 Series Routes Straight Line Diagrams" (PDF). New Jersey Department of Transportation. Retrieved August 29, 2010.
- ^ a b c d Moeur, Richard C. (September 15, 2010). "Special Route Definitions". Manual of Traffic Signs. Retrieved October 1, 2014.[self-published source]
- ^ a b Staff (January 2000). "Establishment and Development of United States Numbered Highways" (PDF). American Association of State Highway and Transportation Officials. Retrieved January 23, 2008.
- ^ "DC Considering Special Routes for Trucks". Fleet Owner. January 5, 2004. Retrieved October 1, 2014.
- ^ Staff. "Traffic Regulations: Route 1 and 9, the Pulaski Skyway". New Jersey Department of Transportation. Retrieved August 6, 2009.
- OCLC 786163525.
- ^ a b Kohrman, Benjamin (August 19, 2005). "MDOT Establishes US 31/Bascule Bridge Emergency Detour Routes" (Press release). Michigan Department of Transportation. Archived from the original on February 13, 2012.
- ^ Fannin, Marc (June 27, 2005). "Michiana Road Photos: Emergency Interstate 94". Roadfan.com.[self-published source]