Sewer Vent

Item details


Name of item:	Sewer Vent
Other name/s:	The Obelisk, Obelisk Sewer Vent; Thornton's Needle
Type of item:	Built
Group/Collection:	Utilities - Sewerage
Category:	Other - Utilities - Sewerage
Location:	Lat: -33.8746730209 Long: 151.2098560630
Primary address:	Elizabeth Street, Sydney, NSW 2000
Parish:	St James
County:	Cumberland
Local govt. area:	Sydney
Local Aboriginal Land Council:	Metropolitan

Boundary:

Within Road Reserve Elizabeth Street. The physical and operational curtilage of the ventshaft is restricted to all the original fabric of the ventshaft and the property upon which it is constructed.

All addresses

Street Address	Suburb/town	LGA	Parish	County	Type
Elizabeth Street	Sydney	Sydney	St James	Cumberland	Primary Address
Bathurst Street	Sydney	Sydney			Alternate Address

Owner/s

Organisation Name	Owner Category	Date Ownership Updated
Sydney Water	State Government

Statement of significance:


	The first planned sewerage system in the city of Sydney was completed in 1857. The Obelisk was the first major sewer vent constructed and the only ventshaft constructed entirely of sandstone. The Obelisk Vent was an ambitious achievement at the time of construction owing to its utilitarian purpose. It is historically significant as one of the oldest items of infrastructure in the early City sewerage system. It has landmark qualities, providing a fitting terminus to the eastern end of Bathurst Street. It is also significant for its contribution to the streetscape of Elizabeth Street, its visual role in the axial vistas of Sydney, and as a significant object within Hyde Park.
	Date significance updated: 30 Nov 01
	Note: The State Heritage Inventory provides information about heritage items listed by local and State government agencies. The State Heritage Inventory is continually being updated by local and State agencies as new information becomes available. Read the OEH copyright and disclaimer.

Description


Designer/Maker:	Public Works Department
Builder/Maker:	Public Works Department
Physical description:	A simple masonry shaft consisting of a sandstone base, brick column and a decorative bronze ventilator apex. The obelisk was complete in 1857. It is 75' high, 15' square at its base (originally). Above-ground it has an Egyptian-style designed pedestal, surmounted by an obelisk with an ornamental, open top (the vent). This was originally made of copper (Sydney Water, 2005).
	Date condition updated:09 Jan 01
Further information:	See inventories for the Main Northern Ocean Outfall Sewer, Lewisham Sewer Ventshaft, Marrickville Sewer Ventshaft, Glebe and Bellevue Hill Sewer Ventshafts for other details relating to sewer vents.


Current use:	Monument, Stormwater vent for the Bennelong Stormwater Channel
Former use:	Aboriginal land, park, sewer vent

History

Historical notes:

The "Eora people" was the name given to the coastal Aborigines around Sydney. Central Sydney is therefore often referred to as "Eora Country". Within the City of Sydney local government area, the traditional owners are the Cadigal and Wangal bands of the Eora. There is no written record of the name of the language spoken and currently there are debates as whether the coastal peoples spoke a separate language "Eora" or whether this was actually a dialect of the Dharug language. Remnant bushland in places like Blackwattle Bay retain elements of traditional plant, bird and animal life, including fish and rock oysters.

With the invasion of the Sydney region, the Cadigal and Wangal people were decimated but there are descendants still living in Sydney today. All cities include many immigrants in their population. Aboriginal people from across the state have been attracted to suburbs such as Pyrmont, Balmain, Rozelle, Glebe and Redfern since the 1930s. Changes in government legislation in the 1960s provided freedom of movement enabling more Aboriginal people to choose to live in Sydney (sourced from Anita Heiss, "Aboriginal People and Place", Barani: Indigenous History of Sydney City http://www.cityofsydney.nsw.gov.au/barani ).

Hyde Park:
In 1854 a Hyde Park Improvement Committee was formed to improve the layout and amenity of the park. Improvements included a formal layout, with plantings of Moreton Bay figs and a stone dwarf wall (1876) surrounding the entire park (which still exists today)(Sydney Water, 2005).

The obelisk was the first and only major sewer vent on Sydney's first planned sewerage system, which was completed
by the City of Sydney in 1857. It was built to eliminate noxious gases from the sewer bringing the foul gases out above street level. The system consisted of five principal outfall sewers discharging to the harbour at Blackwattle Bay, Darling Harbour, Sydney Cove, Bennelong Point and Woolloomoolloo. The obelisk was unveiled in December 1857 by then Lord Mayor of the City of Sydney, George Thornton. It attracted much acclaim as a monument until citizens became aware of its true purpose. Sydneysiders nicknamed it 'Thornton's Stink Pot' or 'Thornton's Smelling Bottle', amused that the elaborate Egyptian style brick and sandstone column was actually a sewer vent (ibid, 2005).(ibid, 2005).

Ventilation of sewers was introduced in the 1850s to protect the workers from poisonous gasses accumulating in the conduits. It was considered a major innovation of the sewerage process, although of somewhat ambiguous popularity (ibid, 2005). There are two types of sewer vents in the Sydney system; educt and induct. Induct vents draw air into a sewerage system to areate pipelines. Educt vents allow gases to escape when the gas is lighter than air. The shape of the cowling on the older types of vents were set to produce either eduction or indcution whenever there is a natural breeze. This (Hyde Park vent) is an educt shaft, a simple masonry shaft modelled on Cleopatra's Needle (now situated on the Thames Embankment, London). Vents are for the safety of personnel as well as to prevent corrosion by chemical decay. The ventilation of sewers is a very important facet of continued operation of a sewerage system. Poor ventilation can result in serious odour problems and breakdown in fabric.

Despite the controversy the Obelisk provided a model on which the rest of the city's tall brick vent shafts were based in 1875. Eventually the majority of these ornate structures were replaced with smaller steel tube vents at more regular intervals (ibid, 2005). A Sydney Morning Herald article documenting its construction on 10/9/1857 noted 'on the pedestal a fireplace will be constructed, and here a fire will be continually kept burning for the purposes of rarefying the air and consuming the noxious gases as they escape upwards'. There is no evidence of this flame being lit. Rather, it appears that water vapour was used to smother gases exiting the vent, as a small pipe can be seen protruding from the ground near the base of the obelisk on the eastern side (ibid, 2005).

In 1875 the Sydney City and Suburban Health Board recommended in its 6th Progress Report, that 2 sewerage schemes be constructed to deal with health problems being faced due to the pollution within Sydney Harbour. From that period several methods of ventilating the sewers were investigated to deal with the disease, odour, pressure and chemical problems being experienced within the sewers.

Of the methods investigated and adopted, including street vents, house vents (cast iron traps and water traps) and flues, the tall ventshafts were determined by Mr. J.M.Smails in several reports to the government of the day, to be the most efficient way of dispersing the pressure and gases found within the sewers.

Initially, after the Obelisk, sewer ventshafts were built in brick, ornate and fairly major features in the city landscape. This technology was replaced with smaller, steel tube vents, used at intervals of approximately every 350m of sewer (ibid, 2005).

Plans of the Obelisk and surrounds, c1886 show the 1876 stone dwarf wall, with six smaller obelisks surrounding the vent shaft. It is unknown whether these smaller obelisks were constructed as part of Hyde Park improvements or when the Obelisk was originally constructed, in 1857. It is believed by some that these smaller obelisks formed a sundial (ibid, 2005).

The obelisk itself has remained largely intact, however there have been various maintenance works including the replacement of the copper vent and changes to the configuration of the obelisk's surrounds (ibid, 2005).

In the early 1900s, Elizabeth Street was widened to alleviate traffic congestion. The western face of the sandstone obelisk base was shaved off around 1917 and two of the smaller obelisks were removed, possibly as part of these works (Sydney Water, 2005).

By the 1950s all of the smaller obelisks had been removed (ibid, 2005).

The Obelisk was handed over to the Metropolitan Water, Sewerage and Drainage Board in 1889 and is still owned and managed by Sydney Water, although it has not been an operating part of the sewerage system since the 1970s. It is now used to ventilate the Bennelong Stormwater Channel (formerly known as the Bennelong Combined Sewer and Stormwater system)(ibid, 2005).

The Obelisk was listed on the NSW State Heritage Register in 2002 (ibid, 2005).

Historic themes

Australian theme (abbrev)	New South Wales theme	Local theme
1. Environment-Tracing the evolution of a continent's special environments	Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures.	Parks-
1. Environment-Tracing the evolution of a continent's special environments	Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures.	Other open space-
1. Environment-Tracing the evolution of a continent's special environments	Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures.	Park reserve-
1. Environment-Tracing the evolution of a continent's special environments	Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures.	Changing the environment-
2. Peopling-Peopling the continent	Aboriginal cultures and interactions with other cultures-Activities associated with maintaining, developing, experiencing and remembering Aboriginal cultural identities and practices, past and present.	Aboriginal Culture-
2. Peopling-Peopling the continent	Aboriginal cultures and interactions with other cultures-Activities associated with maintaining, developing, experiencing and remembering Aboriginal cultural identities and practices, past and present.	All nations - place of first contact between Aboriginal and European peoples-
2. Peopling-Peopling the continent	Aboriginal cultures and interactions with other cultures-Activities associated with maintaining, developing, experiencing and remembering Aboriginal cultural identities and practices, past and present.	Cadigal tribe - Eora nation-
2. Peopling-Peopling the continent	Ethnic influences-Activities associated with common cultural traditions and peoples of shared descent, and with exchanges between such traditions and peoples.	Demonstrating Italian hermit practices-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Unseen but Present-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Sydney and Australian Landmark-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Developing local, regional and national economies-National Theme 3
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Park-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Landscapes and parklands of distinctive styles-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Landscapes of institutions - productive and ornamental-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Gardens and landscapes reminiscent of an 'old country'-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Landscapes of urban amenity-
3. Economy-Developing local, regional and national economies	Events-Activities and processes that mark the consequences of natural and cultural occurences	Holding opening and dedication ceremonies-
3. Economy-Developing local, regional and national economies	Events-Activities and processes that mark the consequences of natural and cultural occurences	Developing local landmarks-
3. Economy-Developing local, regional and national economies	Events-Activities and processes that mark the consequences of natural and cultural occurences	Commemorating a major event-
3. Economy-Developing local, regional and national economies	Health-Activities associated with preparing and providing medical assistance and/or promoting or maintaining the well being of humans	Providing sewerage systems-
3. Economy-Developing local, regional and national economies	Health-Activities associated with preparing and providing medical assistance and/or promoting or maintaining the well being of humans	Encouraging public recreation in parks-
3. Economy-Developing local, regional and national economies	Technology-Activities and processes associated with the knowledge or use of mechanical arts and applied sciences	Technologies for sanitation-
3. Economy-Developing local, regional and national economies	Technology-Activities and processes associated with the knowledge or use of mechanical arts and applied sciences	Technologies of tunnel construction-
3. Economy-Developing local, regional and national economies	Technology-Activities and processes associated with the knowledge or use of mechanical arts and applied sciences	(none)-
4. Settlement-Building settlements, towns and cities	Accommodation-Activities associated with the provision of accommodation, and particular types of accommodation – does not include architectural styles – use the theme of Creative Endeavour for such activities.	Building settlements, towns and cities-National Theme 4
4. Settlement-Building settlements, towns and cities	Accommodation-Activities associated with the provision of accommodation, and particular types of accommodation – does not include architectural styles – use the theme of Creative Endeavour for such activities.	Architectural design-
4. Settlement-Building settlements, towns and cities	Land tenure-Activities and processes for identifying forms of ownership and occupancy of land and water, both Aboriginal and non-Aboriginal	Administering and alienating Crown lands-
4. Settlement-Building settlements, towns and cities	Land tenure-Activities and processes for identifying forms of ownership and occupancy of land and water, both Aboriginal and non-Aboriginal	Changing land uses - from rural to suburban-
4. Settlement-Building settlements, towns and cities	Land tenure-Activities and processes for identifying forms of ownership and occupancy of land and water, both Aboriginal and non-Aboriginal	Resuming private lands for public purposes-
4. Settlement-Building settlements, towns and cities	Land tenure-Activities and processes for identifying forms of ownership and occupancy of land and water, both Aboriginal and non-Aboriginal	Changing land uses - from suburban to urban-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Macquarie's town layout-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	living in the city-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Early Sydney Street-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	19th century suburban developments-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	19th Century Infrastructure-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Creating landmark structures and places in suburban settings-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Impact of railways on suburban development-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Developing suburbia-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Developing civic infrastructure and amenity-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Beautifying towns and villages-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Creating landmark structures and places in urban settings-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Urban landscapes inspiring creative responses-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Planning relationships between key structures and town plans-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Creation of railway towns-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	living in the suburbs-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Impacts of railways on urban form-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Suburban Consolidation-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Suburban Expansion-
4. Settlement-Building settlements, towns and cities	Utilities-Activities associated with the provision of services, especially on a communal basis	Water and drainage-
4. Settlement-Building settlements, towns and cities	Utilities-Activities associated with the provision of services, especially on a communal basis	Suburban Consolidation-
4. Settlement-Building settlements, towns and cities	Utilities-Activities associated with the provision of services, especially on a communal basis	Water supply-
4. Settlement-Building settlements, towns and cities	Utilities-Activities associated with the provision of services, especially on a communal basis	Providing sewers and stormwater outlets-
4. Settlement-Building settlements, towns and cities	Utilities-Activities associated with the provision of services, especially on a communal basis	Examples of early water and sanitation systems (wells and cess pits)-
4. Settlement-Building settlements, towns and cities	Utilities-Activities associated with the provision of services, especially on a communal basis	(none)-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Working on public infrastructure projects-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Working complex machinery and technologies-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Working with hand tools and implements-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	State government-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Local government-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - administration of land-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - public land administration-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - administering a public health system-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - building and operating public infrastructure-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Administrative Centre, 1839-62-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - conserving cultural and natural heritage-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Direct vice-regal governance (pre 1856)-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Local and municipal self-governance-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - parks and open spaces-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - providing sewerage treatment-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - providing reticulated water-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - public water supply-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Public works-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Suburban Consolidation-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Industrial buildings-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Monuments-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Architectural styles and periods - Victorian Egyptian Revival-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Parks and public gardens-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Applying architectural design to utlilitarian structures-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	work of stonemasons-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Architectural styles and periods - Victorian (mid)-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Landscaping - Victorian period-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Designing in an exemplary architectural style-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Designing landscapes in an exemplary style-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Designing structures to emphasise their important roles-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Building in response to climate - ventilation devices-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Creating an icon-
8. Culture-Developing cultural institutions and ways of life	Domestic life-Activities associated with creating, maintaining, living in and working around houses and institutions.	Ways of life 1850-1900-
8. Culture-Developing cultural institutions and ways of life	Domestic life-Activities associated with creating, maintaining, living in and working around houses and institutions.	Ways of life 1900-1950-
8. Culture-Developing cultural institutions and ways of life	Domestic life-Activities associated with creating, maintaining, living in and working around houses and institutions.	Living in suburbia-
8. Culture-Developing cultural institutions and ways of life	Domestic life-Activities associated with creating, maintaining, living in and working around houses and institutions.	Living above a shop or office-
8. Culture-Developing cultural institutions and ways of life	Leisure-Activities associated with recreation and relaxation	Outdoor relief-
8. Culture-Developing cultural institutions and ways of life	Leisure-Activities associated with recreation and relaxation	Visiting gardens-
8. Culture-Developing cultural institutions and ways of life	Leisure-Activities associated with recreation and relaxation	Activities associated with relaxation and recreation-
8. Culture-Developing cultural institutions and ways of life	Leisure-Activities associated with recreation and relaxation	Visiting heritage places-
8. Culture-Developing cultural institutions and ways of life	Leisure-Activities associated with recreation and relaxation	Going to the park-
8. Culture-Developing cultural institutions and ways of life	Leisure-Activities associated with recreation and relaxation	Gathering at landmark places to socialise-
8. Culture-Developing cultural institutions and ways of life	Leisure-Activities associated with recreation and relaxation	Enjoying public parks and gardens-
8. Culture-Developing cultural institutions and ways of life	Social institutions-Activities and organisational arrangements for the provision of social activities	Places of informal community gatherings-
8. Culture-Developing cultural institutions and ways of life	Social institutions-Activities and organisational arrangements for the provision of social activities	Belonging to an historical society or heritage organisation-
8. Culture-Developing cultural institutions and ways of life	Social institutions-Activities and organisational arrangements for the provision of social activities	Developing local clubs and meeting places-
9. Phases of Life-Marking the phases of life	Persons-Activities of, and associations with, identifiable individuals, families and communal groups	Associations with Ald. George Thornton, Lord Mayor of Sydney City-
9. Phases of Life-Marking the phases of life	Persons-Activities of, and associations with, identifiable individuals, families and communal groups	Associations with the Hyde Park Improvement Committee-

Assessment of significance


SHR Criteria a) [Historical significance]	The Obelisk was the first sewer ventshaft built to eliminate noxious gases from the sewer at levels that would not be detected by the residents of the city. The ventshaft was built to replace the street gratings that had been used to ventilate the sewer system.
SHR Criteria c) [Aesthetic significance]	The Obelisk is a sandstone ventshaft which displays the classical architecture and technology of the late nineteenth century. It is a landmark feature within Hyde park and Sydney, which is visible as a major feature at the end of Bathurst Street.
SHR Criteria d) [Social significance]	It is significant in the development of the ventilation of the sewerage system of Sydney and has been identified by the National Trust Australia (NSW).
SHR Criteria e) [Research potential]	The design and placement of the Obelisk was used to understand the behaviour of gases within the sewerage system and how to best design vents to help eliminate the gases safely. The ventshaft was also to relieve the gaseous pressure that built up within the sewer system.
SHR Criteria f) [Rarity]	The Obelisk is unique in NSW. It is one of the oldest items of infrastructure in the early city sewerage system. It was the first ventshaft built to eliminate noxious gases from the city's sewer system.
SHR Criteria g) [Representativeness]	The Obelisk Sewer Ventshaft is the only example of a sewer ventsahft constructed of sandstone within the Sydney Water system, but is representative of sewer ventilation methods.
Integrity/Intactness:	Considerably intact apart from alterations to its base.
Assessment criteria:	Items are assessed against the State Heritage Register (SHR) Criteria to determine the level of significance. Refer to the Listings below for the level of statutory protection.

Recommended management:

Manage the place and its significant components in accordance with the Heritage Council State Owned Heritage Asset Management Guidelines and the Minimum Standards of Maintenance and Repair in the NSW Heritage Regulations. Manage significant site elements in accordance with a Conservation Management Plan (CMP). If no CMP exists, consult with Asset Management Commercial Services with respect to commissioning a CMP. When commissioning a CMP, do so in accordance with the Model Brief for CMPs available on ConnectNet. Seek endorsement of the CMP from the Heritage Council of NSW. Works undertaken in accordance with a Heritage Council-endorsed CMP do not require further approval under the NSW Heritage Act. Involve heritage professionals as required under the terms of the CMP, or as otherwise determined necessary. Review CMP every 5 years or in a major change of circumstances, whichever is sooner. Review of a CMP should only be undertaken following consultation with Asset Management Commercial Services . When commissioning a CMP review, do so in accordance with the Model Brief for CMPs available on ConnectNet. Where no CMP is in place, or where works are outside the scope of the existing CMP, assess heritage impacts of proposed works in accordance with Sydney Water Environment Impact Assessment guidelines (e.g. undertake a Heritage Assessment and/or Statement of Heritage Impact as required, obtain Heritage Council approval as required). Consult with the Heritage Manager, Environment and Innovation, when major works are planned which affect items of State heritage significance. Undertake archival and photographic recording before major changes, in accordance with Heritage Council guidelines. Lodge copies of the archival record with the Sydney Water Archives and the NSW Heritage Office. Where the item is listed in a Local Environmental Plan Schedule of Heritage items, determine if works are exempt from approval under the LEP provisions. Where works are not exempt, obtain necessary approvals from the local council, in accordance with SWC EIA Guidelines.

Recommendations

Management Category	Description	Date Updated
Recommended Management	Produce a Conservation Management Plan (CMP)
Recommended Management	Prepare a maintenance schedule or guidelines
Recommended Management	Carry out interpretation, promotion and/or education

Procedures /Exemptions

Section of act	Description	Title	Comments	Action date
21(1)(b)	Conservation Plan submitted for endorsement	The Obelisk CMP, by Sydney Water for Sydney Water, dated August 2005	CMP endorsed by the Heritage Council on 23 September 2005 for a period of five years, expires 23 September 2010.	Sep 23 2005
57(2)	Exemption to allow work	Standard Exemptions	ORDER UNDER SECTION 57(2) OF THE HERITAGE ACT 1977 Standard exemptions for engaging in or carrying out activities / works otherwise prohibited by section 57(1) of the Heritage Act 1977. I, Donald Harwin, the Special Minister of State pursuant to subsection 57(2) of the Heritage Act 1977, on the recommendation of the Heritage Council of New South Wales do by this Order, effective 1 December 2020: 1. revoke the order made on 11 July 2008 and published on pages 91177 to 9182 of Government Gazette Number 110 of 5 September 2008 and varied by notice published in the Government Gazette on 5 March 2015; and 2. grant the exemptions from subsection 57(1) of the Heritage Act 1977 that are described in the attached Schedule. Donald Harwin Special Minister of State Signed this 9th Day of November 2020. To view the standard exemptions for engaging in or carrying out activities / works otherwise prohibited by section 57(1) of the Heritage Act 1977 click on the link below.	Nov 13 2020

Standard exemptions for works requiring Heritage Council approval

Listings

Heritage Listing	Listing Number	Gazette Date	Gazette Number	Gazette Page
Heritage Act - State Heritage Register	01642	15 Nov 02	220	9711
Heritage Act - s.170 NSW State agency heritage register	285160
National Trust of Australia register	6186	25 May 75
Register of the National Estate	001801	21 Mar 78

Study details

Title	Year	Number	Author	Inspected by	Guidelines used
Sydney Water Heritage Study	1996	285160	Graham Brooks and Associates Pty Ltd	GRAHAM BROOKS AND ASSOCIATES PTY LTD 1 JULY 1996	Yes
Alexandra Canal Conservation Management Plan	2004		NSW Department of Commenrce, Heritage Design Services		Yes

References, internet links & images

Type	Author	Year	Title	Internet Links
Tourism		2007	Obelisk	View detail
Tourism	Attraction Homepage	2007	Obelisk	View detail
Written	Sydney Water	2005	The Obelisk - Sydney's first major sewer vent

Note: internet links may be to web pages, documents or images.

(Click on thumbnail for full size image and image details)

Data source


The information for this entry comes from the following source:
Name:	Heritage NSW
Database number:	5053881
File number:	H05/00094

Every effort has been made to ensure that information contained in the State Heritage Inventory is correct. If you find any errors or omissions please send your comments to the Database Manager.

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