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For other uses, see Manhole (disambiguation).
PMG manholes in a city street, Perth, Western Australia.
Manhole in Belo Horizonte, Brazil.
This is a sewer manhole, exposed during construction. Typically, only the top ring and manhole cover (not pictured) would be visible.
Manhole cover of precast concrete in Germany

A manhole (alternatively utility hole, cable chamber, maintenance hole, inspection chamber, access chamber or confined space) is the top opening to an underground utility vault used to house an access point for making connections or performing maintenance on underground and buried public utility and other services including sewers, telephone, electricity, storm drains and gas.


Manhole closings are protected by a manhole cover (also known as a "biscuit"[citation needed]), a flat plug designed to prevent accidental or unauthorized access to the manhole. Those plugs are traditionally made of metal, but may be constructed from precast concrete, glass reinforced plastic or other composite material (especially in Europe, or where cover theft is of concern).

Manholes are usually outfitted with metal, polypropylene, or fiberglass steps installed in the inner side of the wall to allow easy descent into the utility space. Because of legislation restricting acceptable manual handling weights, Europe has seen a move toward lighter weight composite manhole cover materials, which also have the benefits of greater slip resistance and electrical insulating properties.

The access openings are usually circular in shape to prevent accidental fall of the cover into the hole.

Manholes are generally found in urban areas, in streets and occasionally under sidewalks. In rural and undeveloped areas, services such as telephone and electricity are usually carried on utility poles or even pylons rather than underground.

Composite manholes[edit]

Composite (fiberglass) manholes are commonly used in applications where infiltration, exfiltration, or corrosion by hydrogen sulfide (from sewer gas) are a concern, or where structures need to be factory integrated into a manhole before placement.

Structures commonly integrated into composite manholes include:

  • Flow inverts[1]
  • Flumes[2]
  • Drop structures from higher elevation flows to lower elevation discharge pipes

Occasionally, composite manholes will integrate:

  • Weirs[3]
  • Storm water screening structures[4]
  • Sewage grinders[5]
  • Energy absorbing structures to dissipate undesirable flow stream turbulence or velocity[6]

Hazards caused by stray voltage in manholes[edit]

In urban areas, stray voltage issues have become a significant concern for utilities. In 2004, Jodie S. Lane was electrocuted after stepping on a metal manhole cover, while walking her dog in New York City.[7] One solution is the Electrified Cover Safeguard invention, which is an on-site, real-time stray voltage warning system which is being used in the street lights in New York City and is also being tested by ConEd and other utilities and municipalities in England, Europe, and Japan.[citation needed]

See also[edit]



  • Isles, Paul (2010). "Dover Engineering Works". Dover Life Magazine

Further reading[edit]

  • Ascher, Kate ; researched by Wendy Marech (2007). The works : anatomy of a city (Reprint. ed.). New York: Penguin Press. ISBN 978-0143112709. 

Original courtesy of Wikipedia: http://en.wikipedia.org/wiki/Manhole — Please support Wikipedia.
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7411 news items

WSOC Charlotte
Tue, 30 Sep 2014 18:41:15 -0700

A man was looking at a car for sale parked in front of the Apartments of Sailboat Bay Tuesday night when he fell into a 25-foot manhole that had a loose cover, officials said. The manhole was off Albemarle Road near Sharon Amity Road. Officials said he ...
Tue, 30 Sep 2014 22:03:45 -0700

In the latest incidents, two manhole covers were reported missing Monday from the intersections of Union and Franklin streets and Harrison Street and Woodbridge Drive. Other manhole covers have been reported taken from Malibu Drive and the ...


Tue, 30 Sep 2014 11:18:43 -0700

A Parkchester Macy's and post office were evacuated Tuesday after a manhole fire broke out. View Full Caption. Creative Commons/Peter Stehlik. THE BRONX — A Parkchester Macy's and a post office were evacuated after a transformer fire sent smoke ...

The Nation

The Nation
Tue, 30 Sep 2014 19:36:58 -0700

LAHORE - A four-year-old boy died after falling into an open manhole near Pully stop in Green Town, police sources said Tuesday. Rickshaw-driver Muhammad Ayyaz along with his son Zahid toured Quaid-e-Azam Industrial Estate area on Tuesday ...
The News International
Tue, 30 Sep 2014 19:37:30 -0700

A four-year-old boy died after falling into a manhole in the Green Town area on Tuesday. Police said the boy went outside home while playing and disappeared. The family began a search for the minor and later spotted him lying in a manhole. He was ...

The Express Tribune

The Express Tribune
Tue, 30 Sep 2014 15:30:00 -0700

LAHORE: Several residents of the Quaid-i-Azam Industrial Estate staged a protest demonstration on Peco Road on Tuesday after a four-year old died after falling into an open manhole. The protesters chanted slogans against the administration for not ...
Yahoo! Maktoob News
Tue, 30 Sep 2014 14:56:15 -0700

Two workers had to be rescued after they got trapped inside a manhole. One worker was cleaning the manhole but fell inside and the other also fell while trying to pull his colleague out. Northern Borders Civil Defense spokesman Cap. Abdulrahman ...


Wed, 03 Sep 2014 22:06:18 -0700

UPDATE (Thur., September 4, 2014) The director of the Conyers Public Works and Transportation Dept., Brad Sutton, told 11Alive News that he's found out the manhole is an AT&T "vault," a manhole that gives AT&T crews access to underground lines and ...

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