Image of a pipe

A sewer is an artificial conduit (or pipe) or system of conduits used to carry and remove sewage (human liquid waste) and to provide drainage. Sewage is the mainly liquid Waste containing some solids produced by humans which typically consists of washing water Feces, Urine, laundry waste and other In the 21st century developed world, sewers are usually pipelines that begin with connecting pipes from buildings to one or more levels of larger underground horizontal mains, which terminate at sewage treatment facilities. Sewage treatment, or domestic wastewater treatment, is the process of removing Contaminants from Wastewater, both Runoff ( Effluents Vertical pipes, called manholes, connect the mains to the surface. A manhole (alternatively utility hole, maintenance hole or access chamber) is the top opening to an underground Utility vault used to house Sewers are generally gravity powered, though pumps may be used if necessary. For information on Wikipedia project-related discussions see WikipediaVillage pump.

Storm sewers (also storm drains) are large pipes that transport storm water runoff from streets to natural bodies of water or absorptive areas (also considered as part of the sewer), to avoid street flooding. A storm drain, storm sewer ( US) stormwater drain ( Australia and New Zealand) or surface water system ( UK) Surface runoff is a term used to describe when soil is infiltrated to full capacity and excess Water, from Rain, Snowmelt, or other sources flows A street is a Public thoroughfare in the built environment It is a Public parcel of land adjoining Buildings in an urban context When the two systems are operated separately, the sewer system that is not the set of storm drains is called a sanitary sewer. A sanitary sewer (also called especially in the UK a foul sewer) is a type of underground carriage system for transporting Sewage from houses or industry to In the United Kingdom legal system storm sewers are not differentiated from foul sewers (sanitary sewers) both being referred to as sewers. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located However in practice storm sewers are most commonly called Highway drains or gulleys. Catch-basins referred to below are therefore called gully-pots in the UK.

Storm sewer function

Most storm sewers are provided with gratings or grids prevent large objects from falling into the sewer system. Catchbasins are immediately below the vertical pipes connecting the surface to the storm sewers. While sewer grates covering the vertical pipes with fairly widely spaced grating bars so that the flow of water is not impeded. A grating is any regularly spaced collection of essentially identical Parallel, elongated elements Consequently many small objects can fall through. Most of these objects are caught by the catchbasin immediately below the grating. Water from the top of the catchbasin drains into the sewer proper. The catchbasin serves much the same function as the "trap" in household wastewater plumbing in trapping objects. Plumbing, from the Latin plumbum for Lead, is the skilled trade of working with pipes, tubing and Plumbing fixtures for In the United States of America, unlike the trap, the catchbasin does not necessarily prevent sewer gases such as hydrogen sulfide and methane from escaping. Hydrogen sulfide (or hydrogen sulphide) is the Chemical compound with the formula H 2 S. Methane is a Chemical compound with the molecular formula. It is the simplest Alkane, and the principal component of Natural gas. However in the United Kingdom, where they are called gulley-pots, they are designed as true water-filled traps and do block the egress of gases and rodents. Most catchbasins will contain stagnant water during the drier parts of the year and can be used by mosquitoes for breeding. Water stagnation occurs when Water stops flowing Stagnant water can be a major Environmental hazard. Mosquitoes are insects in the family Culicidae. They have a pair of scaled wings a pair of Halteres, a slender body and long legs Catchbasins require regular cleaning to remove the trapped debris. Municipalities typically have large vacuum trucks that perform this task.

Storm sewer water may be treated or not, depending on jurisdiction. Treatment helps purify the storm water before being restored to a natural body of water. Storm water may become contaminated while running down the road or other impervious surface, or from lawn chemical run-off, before entering the sewer. Impervious surfaces are mainly artificial structures such as pavements rooftops sidewalks roads and parking lots - covered by impenetrable materials such as asphalt concrete The separation of storm sewers from sanitary sewers helps to prevent sewage treatment plants becoming over-whelmed by the huge influx of water during a rainstorm. This can result resulting in untreated sewage being discharged into the environment.

Usually storm sewers are designed to drain the storm water to rivers or streams as previously described. In the city of Cleveland, Ohio, for example, all new catch basins installed have inscriptions on them not to dump any waste, and usually include a fish imprint as well. Cleveland is a City in the US state of Ohio and the County seat of Cuyahoga County, the most populous county in the state Washington, D.C. and other cities with older combined systems have this problem due to a large influx of storm water after every heavy rain. Washington DC ( formally the District of Columbia and commonly referred to as Washington, the District, or simply D A combined sewer is a type of Sewer system which provides partially separated channels for sanitary Sewage and Stormwater runoff. Some cities have dealt with this by adding large storage tanks or ponds to hold the water until it can be treated. Chicago has a system of tunnels underneath the city for storing its stormwater. Chicago (ʃɪˈkɑːgoʊ is the largest City by population in the state of Illinois and the American Midwest of the United States. ^[1]

However, completely separating storm sewers from sanitary sewers often means no treatment of stormwater, which is not desirable either, as the first flush from storm runoff can be extremely dirty. A sanitary sewer (also called especially in the UK a foul sewer) is a type of underground carriage system for transporting Sewage from houses or industry to Stormwater is a term used to describe water that originates during precipitation events Runoff into storm sewers can be minimized by including sustainable urban drainage systems (UK term) or low impact development practices (U. Sustainable Drainage Systems (SuDS sometimes known as Sustainable Urban Drainage Systems (SUDS are designed to reduce the potential impact of new and existing developments Low Impact Development (LID is a term used in the United States to describe a land planning and engineering design approach to managing Stormwater S. term) into municipal plans. Eaves troughs should not discharge directly into the storm sewer system but rather onto the ground where it has a chance to soak into the soil. Where possible, storm water runoff should be directed to unlined ditches before flowing into the storm sewers, again to allow the runoff to soak into the ground.

Separation of undesired runoff can be done within the storm sewer system, but such devices are new to the market and can only be installed with new development or during major upgrades. They are referred to as oil-grit separators (OGS) or oil-sediment separators (OSS). They consist of a specialized manhole chamber, and use the water flow and/or gravity to separate oil and grit. A manhole (alternatively utility hole, maintenance hole or access chamber) is the top opening to an underground Utility vault used to house

History

The earliest covered sewers uncovered by archaeologists are in the regularly planned cities of the Indus Valley Civilization. The Indus Valley Civilization (Mature period 2600&ndash1900 BCE abbreviated IVC, was an ancient Civilization that flourished in the Indus River basin In ancient Rome, the Cloaca Maxima, considered a marvel of engineering, disgorged into the Tiber. The Cloaca Maxima was one of the world's earliest Sewage systems The Tiber ( Latin Tiberis, Italian Tevere) is the third-longest River in Italy, rising in the Apennine mountains In medieval European cities, small natural waterways used for carrying off wastewater were eventually covered over and functioned as sewers. London's River Fleet is such a system. The River Fleet is the largest of London 's subterranean rivers It formerly flowed on the surface Open drains along the center of some streets were known as 'kennels' (= canals, channels). This article concerns shelter for Dogs For the missile with the code name "kennel" see AS-1 Kennel A kennel is the name The 19th century brick-vaulted sewer system of Paris offers tours for tourists. Paris (ˈpærɨs in English; in French) is the Capital of France and the country's largest city

Sewers in non-fiction

The image of the sewer recurs in European culture as they were often used as hiding places or routes of escape by the scorned or the hunted, including partisans and resistance fighters in WWII. The only survivors from the Warsaw Uprising and Warsaw Ghetto made their final escape through city sewers. The Warsaw Uprising ( Powstanie Warszawskie) was a World War II struggle by the Polish Home Army ( Armia Krajowa) to liberate Warsaw The Warsaw Ghetto was the largest of the Jewish Ghettos located in the territory of General Government during World War II, established by Some have commented that the engravings of imaginary prisons by Piranesi were inspired by the Cloaca Maxima, one of the world's earliest sewers. Engraving is the practice of incising a design onto a hard usually flat surface by cutting grooves into it A prison, penitentiary, or correctional facility is a place in which individuals are physically confined or interned and usually deprived of a range of The Cloaca Maxima was one of the world's earliest Sewage systems

Sewers in fiction

The theme of traveling through, hiding, or even residing in sewers is a common cliché in media, where unsanitary conditions or the strong smell of sewage are seldom mentioned. A cliché (from French, klɪ'ʃe or cliche is a phrase expression or idea that has been overused to the point of losing its intended force A famous example of sewer dwelling is Teenage Mutant Ninja Turtles.

Sewer alligators

A well-known urban legend, the sewer alligator, is that of giant alligators or crocodiles residing in sewers, especially of major metropolitan areas. An urban legend or urban myth is a form of modern Folklore consisting of stories thought to be factual by those circulating them Sewer alligator stories are part of an Urban legend that date back to the late 1920s and early 1930s The Thomas Pynchon novel, 'V.', features extended passages in which one of the protagonists, Benny Profane, works with a fictional New York City task force to track alligators in the city sewers. Thomas Ruggles Pynchon Jr (born May 8 1937 is an American writer based in New York City, noted for his dense and complex works of Fiction. V is the debut Novel of Thomas Pynchon, published in 1963. It describes the exploits of a discharged U The City of New York for differences between alligators and crocodiles please see Crocodilia An Alligator is a Crocodilian in the Genus His goal is to bag the great albino alligator, reputed to inhabit the system. Albino Alligator is a 1996 film directed by Kevin Spacey in his directorial debut This literary conceit grows from the persistent urban legend that baby pet alligators, flushed down toilets by tourists returning from Florida, continue to live and flourish in the pipes below. An urban legend or urban myth is a form of modern Folklore consisting of stories thought to be factual by those circulating them A toilet is a Plumbing fixture and disposal system primarily intended for the disposal of the bodily wastes: Urine and fecal matter. Florida ( is a state located in the southeastern region of the United States, bordering Alabama to the northwest and Georgia to the

Two public sculptures in New York depict an alligator dragging a hapless victim into a manhole. [1]

Alligators have been known to get into combined storm sewers in the Southeastern United States. Closed-circuit television by a sewer repair company captured an alligator in a combined storm sewer on tape. [2]

Notes

See also

• 1929 Ottawa sewer explosion
• 1992 explosion in Guadalajara
• Brighton sewers
• Buchan trap
• Chemical toilet
• Ecological sanitation
• Grease interceptor
• Humanure
• Infiltration gallery
• Latrine
• London sewerage system
• Orangi Pilot Project
• Outhouse
• Pit toilet
• Septic tank
• Sewage treatment
• Sewer gas destructor lamp
• Waste disposal
• Water pollution