digplanet beta 1: Athena
Share digplanet:

Agriculture

Applied sciences

Arts

Belief

Business

Chronology

Culture

Education

Environment

Geography

Health

History

Humanities

Language

Law

Life

Mathematics

Nature

People

Politics

Science

Society

Technology

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.

Usage[edit]

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]

Notes[edit]

References[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.

30357 news items

WABC-TV

amNY
Wed, 04 Mar 2015 07:33:45 -0800

The N/Q delays, however, were caused by a manhole at Lexington Ave. and 59th St., the MTA said. The FDNY said it responded to a possible track fire at 9:15 a.m. As a result, there were no N/Q trains running in both directions between 57th St.-7th Ave ...

NYU Local

NYU Local
Tue, 03 Mar 2015 10:22:30 -0800

020215MANHOLE25GPM.jpg New York is dangerous. It's a hot mound of wires and concrete. It's not the fellow man that might kill you, it's the manhole. On Feburary 3 , 71 year old brooklynite Salvatore Grillo was on his morning walk with his dog when he ...

Yahoo News

Yahoo News
Sat, 28 Feb 2015 04:00:00 -0800

Police said an underground blast had blown a cast-iron manhole cover skyward and the heavy metallic disk came crashing down on his head. While the seriousness of Grillo's injury is unusual, manhole "events" have become all too common in the country's ...

artnet News

Huffington Post
Wed, 25 Feb 2015 04:00:00 -0800

From the catwalk to the sidewalk: some of Italy's most famous clothing designers have set haute couture aside for once and dedicated their creative verve to embellishing the streets of downtown Milan. Twenty-four manhole covers designed by Giorgio ...

Dunstable Today

Dunstable Today
Wed, 04 Mar 2015 01:42:18 -0800

Nik Shelton, of Anglian Water, said: “We received a call from the local council onFebruary 27 about a damaged manhole cover in the grass verge next to Dunstable Leisure Centre. We inspected the cover the next day and found the frame had been damaged.

New York Times

New York Times
Wed, 04 Feb 2015 11:16:25 -0800

It hardly looks like a weapon, the metal circle stamped “Con Edison” that countless feet have trodden on. It may steam. It may make booming noises. It may hide all kinds of mysterious cables and wires. But mostly, a New York City manhole cover stays put.
 
New York Post
Mon, 02 Feb 2015 15:26:54 -0800

Firefighters and paramedics were already responding to another manhole explosion just a block away when Grillo was injured. “The first explosion sounded like a bomb,” said local resident Scott Shushan, who was in his basement apartment at the time.

amNY

amNY
Sat, 28 Feb 2015 08:30:00 -0800

Police said an underground blast had blown a cast-iron manhole cover skyward and the heavy metallic disk came crashing down on his head. While the seriousness of Grillo's injury is unusual, manhole "events" have become all too common in the country's ...
Loading

Oops, we seem to be having trouble contacting Twitter

Support Wikipedia

A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia. Please add your support for Wikipedia!

Searchlight Group

Digplanet also receives support from Searchlight Group. Visit Searchlight