Bypass (road)

Bypass (road)

A bypass is a road or highway that avoids or "bypasses" a built-up area, town, or village, to let through traffic flow without interference from local traffic, to reduce congestion in the built-up area, and to improve road safety.

If there are no strong land use controls, buildings are built along a bypass, converting it into an ordinary town road, and the bypass may eventually become as congested as the local streets it was intended to avoid. Shopping centres and some other companies often are built there for ease of access, while homes are often avoided for noise reasons.

United Kingdom

The idea of bypasses predates the use of motor vehicles. The first (northern) London bypass, the present Marylebone Road between Paddington and Islington, was started in 1756.

Bypasses can take many years to gain planning approval and funding. Many towns and villages have been campaigning for bypasses for over 30 years e.g. Banwell in North Somerset [] . Bypass routes are often controversial- by definition they require the building of a road carrying heavy traffic where no road previously existed. This creates a conflict between the those who support a bypass to reduce congestion in a built up area, and those who oppose the development of (often rural) undeveloped land.

United States

In the United States, bypass routes are a type of auxiliary route used on an alternative routing of a highway around a town when the main route of the highway goes through the town. The original designation of these routes were "truck routes" to divert through truck traffic away from the town, but the designation was changed to "bypass" in 1959-1960 by AASHTO. However, many "Truck" routes remain where the mainline of the highway is prohibited for trucks.

In a few cases, both a bypass and a business route exist, both with auxiliary signs (i.e. U.S. Highway 60 in Lexington, Kentucky). Bypass routes are less common than business routes. Many of those that existed before the era of Interstate highways have lost their old designations. For example in Missouri, the old bypass route of U.S. Highway 71 to the east of Kansas City, Missouri was decertified as Interstate 435 supplanted, the remainder that existed as suburban surface route becoming Missouri State Highway 291; around St. Louis, Missouri, what had been Bypass U.S. Highway 50 was absorbed into a diversion of U.S. Highway 50 from Interstate 44 and Interstate 64.

In the Interstate highway system in the United States, bypasses and loops are designated with a three digit number beginning with an even digit. Note, however, that this pattern is inconsistent enough that, as in greater Des Moines, Iowa the genuine bypass is the main route (in that case, Interstate 35 and Interstate 80, and the loop into downtown Des Moines is Interstate 235; or as in Omaha, Nebraska, where Interstate 680 traverses their downtown area, which is bypassed by Interstate 80 and Interstate 680.

Another meaning of the term bypass route (usually simply called a "bypass") is a highway that was constructed to bypass an area that is often congested with traffic. This includes Interstate highway beltways and U.S. Highways constructed to circumvent downtown areas. Examples of these are U.S. Route 60 bypassing Williamsburg, Virginia, U.S. Routes 31 and 20 bypassing metro South Bend, Indiana (the St. Joseph Valley Parkway), and Interstate 75 bypassing Tampa and St. Petersburg, Florida. These bypasses usually carry mainline routes rather than auxiliary "bypass" routes.


The term shoofly, while common in rail terminology, can also be applied to a short temporary roadway which bypasses a construction site or other obstruction. [cite web |url= |title=Oklahoma's I-40 Crosstown Expressway: Glossary |accessdate=2008-04-16 |accessmonthday= |accessdaymonth= |accessyear= |author= |last= |first= |authorlink= |coauthors= |date= |year= |month= |format= |work=Oklahoma Department of Transportation |publisher= |pages= |language= |doi= |archiveurl= |archivedate= |quote= ] The U.S. "Manual on Uniform Traffic Control Devices" uses the term "diversion". [MUTCD [ Section 6C.09] ]


In the more densely populated southern part of Sweden many bypasses have been built, both as motorways and ordinary roads. Many cities and villages however still have main roads right through them. Municipality administrations are often lobbying to have a bypass for safety, noise and air quality reasons. In the northern parts of Sweden fewer bypasses have been built, especially in the sparsely populated interior. Here municipality administrations are often lobbying against bypasses, since they are afraid of losing income from road travellers.

Popular references

In The Hitchhiker's Guide to the Galaxy by Douglas Adams, Arthur Dent's home is destroyed to make way for a bypass. A few minutes later, the entire Earth is destroyed by the Vogons to make way for a hyperspace bypass. In chapter 1, Adams explained what a bypass was:

Bypasses are devices that allow some people to dash from point A to point B very fast while other people dash from point B to point A very fast. People living at point C, being a point directly in between, are often given to wonder what’s so great about point A that so many people from point B are so keen to get there, and what’s so great about point B that so many people from point A are so keen to get there. They often wish that people would just once and for all work out where the hell they wanted to be.

See also

*Alternate route
*Business route
*Israeli bypass roads
*Link road
*List of bannered U.S. Highways
*List of Business Routes of the Interstate Highway System
*Ring road


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • bypass road — road with detours around a certain area …   English contemporary dictionary

  • Gawler bypass road — Infobox Australian Road road name = Gawler Bypass Road route route route photo = caption = direction = North South length = 7 start = finish = est = 1980 s through = Evanston, Gawler West, Willaston route = Main North Road Sturt Hwy: exits = Two… …   Wikipedia

  • Bypass — may refer to:Bypass (slang)(digestive), where gas is expelled through anus during the event of a voluntary fecal restriction, thus the gas bypassed through the fecal matter and released via anus. *Bypass (computing), in computing, circumventing… …   Wikipedia

  • Road — This article is about a route, thoroughfare or way that supports travel by a means of conveyance. For a place outside a harbor where a ship can lie at anchor, see Roadstead. For public roads, see Highway. For other routes, see thoroughfare. For… …   Wikipedia

  • Road protest (UK) — Road protest in the United Kingdom usually occurs as a reaction to a stated intention by the empowered authorities to build a new road, or to modify an existing road. Protests may also be made by those wishing to see new roads built or… …   Wikipedia

  • bypass — 1848, of certain pipes in a gasworks, from BY (Cf. by) + PASS (Cf. pass). First used 1922 for road for the relief of congestion; figurative sense is from 1928. The heart operation was first so called 1957 …   Etymology dictionary

  • bypass — [v] avoid blink at, burke, circumnavigate, circumvent, depart from, detour, deviate from, finesse, get around, go around, go around the barn*, ignore, let go, neglect, omit, outflank, pass around, sidestep, skirt, take back road*, wink at;… …   New thesaurus

  • bypass — ► NOUN 1) a road passing round a town for through traffic. 2) a secondary channel or connection to allow a flow when the main one is closed or blocked. 3) a surgical operation to make an alternative passage to aid the circulation of blood. ► VERB …   English terms dictionary

  • Road transport in Peterborough — The City of Peterborough in the East of England has an extensive and well integrated road network, owing partly to its status as a new town. Since the 1960s the city has seen considerable expansion and its various suburbs are linked by a system… …   Wikipedia

  • bypass */ — I UK [ˈbaɪˌpɑːs] / US [ˈbaɪˌpæs] noun [countable] Word forms bypass : singular bypass plural bypasses 1) a road that goes round a town or city so that you can avoid going through its centre the Newbury bypass 2) medical a medical operation to… …   English dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”