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''This page contains information about a typical Venetian wellhead.''  {{for|a list of wellheads|Wellheads}}
''This page contains information about a typical Venetian wellhead.''  {{for|a list of wellheads|Wellheads}}
A wellhead, ''vera da pozzo'', is the only exposed part of the [[well]] system in Venice. The wellhead served as a cap on the well to prevent debris from falling into the well and contaminating the fresh water supply. As the well system is no longer the main source of fresh water for Venetians; the Venetian Wellhead is now only considered public art and a vital aspect of the city's historical and artistic value. see [[Public art preservation]]
<gallery>
[[Image:Diagram of Cistern.png|right|thumb|Diagram of a typical cistern below a wellhead.<ref>Blackwell, Lewis et al.  Preserving Venetian Wellheads.  2000. Pg 21</ref>]]
[[Image:Diagram of Cistern.png|right|thumb|Diagram of a typical cistern below a wellhead.<ref>Blackwell, Lewis et al.  Preserving Venetian Wellheads.  2000. Pg 21</ref>]]
</gallery>
 
==History==
A wellhead, known locally as “''vera da pozzo''”, is the visible cap to an underground [well] that stored and filtered rain water in Venice. The term ‘''vera da pozzo''’ and it’s many alternatives – ''anello, corona, sponda, cinta, parapetto, spalletta'' or ''bocca di pozzo'' – has been in use since as early as the eleventh century. <ref>Rizzi, 1981</ref>
As a centerpiece of many public squares in Venice, “They were always at the center of socialization and interactivity among Venetians” <ref>Wainwright et al., 2000, pg 16</ref>. The typical wellhead features inscriptions and carvings of saints or family crests. The artistic and structural design of each wellhead is indicative of the art period it was built in. <ref>Huse, 1990</ref>


==Historical Source of Fresh Water==
==Retrieving Water==
The rainwater collection system that early Venetians developed was both an effective and practical way to acquire fresh water. Rainwater would be discharged into the squares from the roofs of buildings by a series of stone gutters and lead pipes. From here the water would run to one of the four corner stones surrounding the wellhead, these were perforated stones that were on a slightly lower elevation than the rest of the square (to act as a funnel). The water was then filtered through layers of fine white sand buried beneath the corner stones, in order to sanitize and free the water of any impurities<ref>Venice, The 1911 Classic Encyclopedia, Last modified October 21, 2006, http://www.1911encyclopedia.org/Venice</ref>. After the filtration process, the water would then reach a cistern that would collect and store the fresh water beneath each wellhead. Buckets could then draw up water through the well shaft that connected the cistern to the wellhead<ref>Insula spa and Matteo Alemanno, Venice Preservation and Urban Maintenance( Venice, Italy: Grafiche Veneziane)</ref>.   
Churches were once responsible for locking and unlocking the well at certain times of the day. This was to prevent just anyone from retrieving water from the well at any given time. In order to retrieve water from the well, Venetians typically used ropes to haul buckets of water over the lip of the wellhead. These ropes left grooves in the material of the wellhead as seen below. Some private wellheads have a pulley system installed to retrieve water without damaging the wellhead.
<gallery>
File:ropemark.jpg|The mark resulted from retrieving water with a rope
</gallery>


==Materials==
==Structure==
A typical wellhead has a platform, the main body and lid. Some platforms are made up of up to three steps. <ref>Thomollari, 2004</ref>


===Wellhead===
== Shape ==
All but two of the 217 public wellheads cataloged are composed exclusively of Istria stone, Red Verona marble, or White Verona marble. Istria is stone the most common material, accounting for 79 percent of the wellheads cataloged. Istria is followed by 14 percent Red Verona marble, and seven percent White Verona marble<ref>Blackwell, Lewis et al. Preserving Venetian Wellheads. 2000. Pg 26 – 27</ref>. [[Istria stone]] is a type of limestone that has a gray-green or yellowish color. Lengthy exposure to the atmosphere causes the stone to obtain a whitish appearance through a process called “whitewashing.” Unfortunately, this also makes Istria stone a prime candidate for [[exfoliation]]. [[Verona marble]] is a sedimentary rock composed of organic limestone and fossils. It has either a reddish or whitish color depending on the carbon compounds it contains.
A typical wellhead has an overall cylindrical or square shape. Often the shape of the base and the shape of the rim are different. The shape of the base is consistently circular while the shape of the rim varies between circular, square, hexagonal and octagonal.
 
==Material==
A Wellhead is constructed with either brick, [[Istria stone]], [[Red Verona]] or [[White Verona]]. A brick wellhead however will deteriorate over time and as a result the typical wellhead of today is made of Istria Stone, Red Verona or White Verona with only a few exceptions. See [[Wellheads]] page. Istria stone is a type of limestone that has a gray-green or yellowish color. Lengthy exposure to the atmosphere causes the stone to obtain a whitish appearance through a process called “whitewashing.” Unfortunately, this also makes Istria stone a prime candidate for exfoliation. Verona marble is a sedimentary rock composed of organic limestone and fossils. It has either a reddish or whitish color depending on the carbon compounds it contains.
 
<gallery>
File:018A.jpg|A wellhead made of Istrian Stone
File:020A.jpg|A wellhead made of Red Verona Stone
File:006A.jpg|A wellhead made of White Verona Stone
[[File:pozzi.png|left|thumb|alt=pozzi|cross sectional well diagram from Insula SpA]]
[[File:pozzi.png|left|thumb|alt=pozzi|cross sectional well diagram from Insula SpA]]
</gallery>


===Well Shaft===
==Lid==
While functioning as Venetians main water supply, the actual well shaft that extended from the wellhead to the cistern was made from bricks and lined with a layer of impermeable clay<ref>Insula spa and Matteo Alemanno, Venice Preservation and Urban Maintenance( Venice, Italy: Grafiche Veneziane)</ref>.
The Lid of a wellhead is typically circular in shape and either flat or convex in shape. The material of the lid is typically metal, wood or concrete with a few exceptions.
 
<gallery>
===Cistern===
File:044lid.jpg|A wellhead that has a metal lid
The cisterns were made with large stones and then lined with impermeable clay that prevented the fresh water from leaking out and more importantly prevented salt water from leaking in and contaminating the water supply<ref>Insula spa and Matteo Alemanno, Venice Preservation and Urban Maintenance( Venice, Italy: Grafiche Veneziane)</ref>.
File:047lid.jpg|A wellhead that has a concrete lid
File:IMG 1698.JPG|A wellhead in Chioggia that has a statue as the lid
</gallery>


==Current Water Supply==
==Serving Nature==
Venice is now supplied with water from the mainland, traveling underground through pipes from the commune Trebaseleghe which is filled by 120 artisan wells<ref>Venice. The 1911 Classic Encyclepedia. October 21, 2006. http://www.1911encyclopedia.org/Venice</ref>.
In the past, these wellheads served as access points to fresh water for not only the human population of Venice, but the animals as well. Small, bowl-shaped indentations were made in the platforms of some wellheads. These indentations served as a source of fresh drinking water and as baths for the local wild life.


==See also==
==See also==
*[[Wellheads]]
*[[Wellheads]]
*[[Wellhead Maintenance]]
*[[Wellhead Maintenance]]
*[[Well]]
*[[Wells]]


==References==
==References==

Latest revision as of 22:17, 14 December 2014

This page contains information about a typical Venetian wellhead.

A wellhead, vera da pozzo, is the only exposed part of the well system in Venice. The wellhead served as a cap on the well to prevent debris from falling into the well and contaminating the fresh water supply. As the well system is no longer the main source of fresh water for Venetians; the Venetian Wellhead is now only considered public art and a vital aspect of the city's historical and artistic value. see Public art preservation

History

A wellhead, known locally as “vera da pozzo”, is the visible cap to an underground [well] that stored and filtered rain water in Venice. The term ‘vera da pozzo’ and it’s many alternatives – anello, corona, sponda, cinta, parapetto, spalletta or bocca di pozzo – has been in use since as early as the eleventh century. [1] As a centerpiece of many public squares in Venice, “They were always at the center of socialization and interactivity among Venetians” [2]. The typical wellhead features inscriptions and carvings of saints or family crests. The artistic and structural design of each wellhead is indicative of the art period it was built in. [3]

Retrieving Water

Churches were once responsible for locking and unlocking the well at certain times of the day. This was to prevent just anyone from retrieving water from the well at any given time. In order to retrieve water from the well, Venetians typically used ropes to haul buckets of water over the lip of the wellhead. These ropes left grooves in the material of the wellhead as seen below. Some private wellheads have a pulley system installed to retrieve water without damaging the wellhead.

Structure

A typical wellhead has a platform, the main body and lid. Some platforms are made up of up to three steps. [4]

Shape

A typical wellhead has an overall cylindrical or square shape. Often the shape of the base and the shape of the rim are different. The shape of the base is consistently circular while the shape of the rim varies between circular, square, hexagonal and octagonal.

Material

A Wellhead is constructed with either brick, Istria stone, Red Verona or White Verona. A brick wellhead however will deteriorate over time and as a result the typical wellhead of today is made of Istria Stone, Red Verona or White Verona with only a few exceptions. See Wellheads page. Istria stone is a type of limestone that has a gray-green or yellowish color. Lengthy exposure to the atmosphere causes the stone to obtain a whitish appearance through a process called “whitewashing.” Unfortunately, this also makes Istria stone a prime candidate for exfoliation. Verona marble is a sedimentary rock composed of organic limestone and fossils. It has either a reddish or whitish color depending on the carbon compounds it contains.

Lid

The Lid of a wellhead is typically circular in shape and either flat or convex in shape. The material of the lid is typically metal, wood or concrete with a few exceptions.

Serving Nature

In the past, these wellheads served as access points to fresh water for not only the human population of Venice, but the animals as well. Small, bowl-shaped indentations were made in the platforms of some wellheads. These indentations served as a source of fresh drinking water and as baths for the local wild life.

See also


References

  1. Rizzi, 1981
  2. Wainwright et al., 2000, pg 16
  3. Huse, 1990
  4. Thomollari, 2004

Bibliography

NULL

External Links