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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, sewer hole or confined space) is the top opening to an underground utility vault used to house an access point for making connections, inspection, valve adjustments or performing maintenance on underground and buried public utility and other services including sewers, telephone, electricity, storm drains, district heating and gas.


Manhole closings are protected by a manhole cover, 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]

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.
This page uses Creative Commons Licensed content from Wikipedia. A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia.

34896 news items

The Hindu
Sun, 29 Nov 2015 22:00:00 -0800

For the Metrowater workers, it was routine work. On Saturday, they were going about the job of de-silting the sewer lines in West Mambalam to prevent sewage blocks. However, when they opened the manhole on 6th Street, K.V.Colony, West Mambalam, they ...


Evening Standard
Mon, 30 Nov 2015 10:00:00 -0800

Motorists faced rush hour delays around Kew Bridge tonight after a manhole cover fire led to the closure of Chiswick High Road. Firefighters remained at the scene this evening after flames sparked just before 3.45pm. A spokeswoman for the London Fire ...

The New Indian Express

The New Indian Express
Sun, 29 Nov 2015 16:22:30 -0800

KOCHI: Giving a communal angle to the compensation announced by the State Government to Kozhikode-based autorickshaw driver P Noushad who lost his life while trying to save two labourers who got trapped in a manhole the other day, Sree Narayana ...

The New Indian Express

The New Indian Express
Sat, 28 Nov 2015 15:26:15 -0800

CHENNAI: Residents of KV Colony in West Mambalam, had the shock of their lives on Saturday noon when a woman's body was taken out of a manhole. The woman, later identified as B Devika, was reported missing almost three weeks ago from her ...

The Hindu

The Hindu
Thu, 26 Nov 2015 16:20:24 -0800

Two cleaning workers from East Godavari district of Andhra Pradesh and an autorickshaw driver from the city died of asphyxiation during a maintenance work in one of the sewers in the city on Thursday. The incident took place at around 10.30 a.m. when ...


Sun, 29 Nov 2015 08:31:59 -0800

Thiruvananthapuram: CPM politburo member Pinarayi Vijayan on Sunday lambasted SNDP chief Vellappally Natesan for commenting that Kerala government offered help to Naushad's family as he was a Muslim. Naushad had died while attempting to rescue ...

The Hindu

The Hindu
Sat, 28 Nov 2015 02:30:00 -0800

Residents of Narasinghapuram, Eighth Street, Guindy, are irked that a manhole has not been de-silted with the result that sewage stagnates throughout the year. For the past few years, the blockages in the main manhole located on Narasinghapuram, Eighth ...

KSNT (press release) (registration) (blog)

KSNT (press release) (registration) (blog)
Mon, 23 Nov 2015 16:36:12 -0800

Sylvia Davis, with the City of Topeka, sent KSNT News a statement saying they are aware of the issue, “The City typically receives about two calls each month referencing missing manhole covers for a variety of reasons.” But they said changing the color ...

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