Victoria Dam
Encyclopedia
The Victoria Dam is a water supply
dam
providing water for the city of Perth, Western Australia
. It is situated on the Darling Scarp
near Lesmurdie
, and crosses Munday Brook. Two dams have stood at the present site; the older dam was the first permanent water supply for the colony and also the first dam in Western Australia
.
It stood for almost 100 years before being replaced with the current dam.
, natural bodies of water and rainwater tanks.
With the growth in the population of Perth and Fremantle
, concerns about water quality, pollution and adequate sewage disposal became widespread. Decades of proposals for sewage disposal and water supply systems followed, coupled with disagreement between the Town Councils and the Colony Government about responsibility for this area. An extensive water supply scheme was eventually compiled by the civil engineers Henry John Saunders and James Barratt in June 1887.
The scheme designed by Saunders and Barratt contained full designs, site surveys and runoff estimates, despite no guarantee of approval or financial incentive. The plan included reticulation for both Perth and Fremantle. In July and August 1887, a Legislative Council Select Committee appointed to examine the proposal passed the issue back to local government. Fremantle refused to participate in the water supply scheme, so following the departure from the Civil Engineering partnership of Barratt, Saunders removed Fremantle from the plan.
The Colony Government passed enabling legislation, and some privately-owned land covering the reservoir was resumed
.
Construction was completed in 1891. The scheme, which included pipelines to Kings Park
and a reservoir there on Mount Eliza
, was constructed and operated by the private City of Perth Waterworks Company. The dam became the first permanent water source for Perth.
The concrete dam wall was built using approximately 1,260 tonne
s of cement
imported from England
. The dam wall was a concrete gravity-arch structure, designed in the plan of a large-radius arch. The volume of the concrete in the finished wall was 16,900 cubic metres.
At the time, the catchment area for the reservoir was used for cattle and sheep grazing and also housed several timber mill settlements. As soon after completion as 1892, concerns were raised that this new water source was getting polluted by raw sewage from the timber mills as well as excrement from the livestock.
Several cases of typhoid fever
occurred at a timber mill in the catchment in 1892, at a time when typhoid fever became increasingly prevalent in Perth. Between 1895 and 1900, there were 4047 cases and 425 deaths from typhoid fever in Perth, and the water supply was suspected to be contaminated. In response to this, in 1896 the Colonial Government purchased the scheme, including the dam, pipelines and Mount Eliza reservoir. In 1897, a sample of the water from the reservoir was found to contain the bacteria causing typhoid fever, and strict by-laws were implemented to prosecute any cases of pollution of the water catchment. Also, a channel was cut to divert the Munday Brook water (polluted by the timber mills) away from the reservoir.
The dam as originally constructed featured two small spillway
s. In 1939, one of these was closed and the other expanded.
Water leaking through the dam wall leached
lime
from the concrete, weakening the structure. Efforts to reduce the leaking occurred in 1912, and in 1966 the upstream side of the dam wall was covered with reinforced concrete to reduce further leaking. However, a 1988 review of the dam's design concluded that it lacked sufficient safety margins in the event of floods or earthquakes, and its concrete had degraded to such a level that it could not be repaired, and needed replacement.
The new Victoria Dam wall was constructed just upstream from the old dam using roller-compacted concrete
(RCC), rather than the more traditional method of large concrete pours or earthfill. It was the first dam built in Western Australia using this method, and at the time was the largest of this type built in Australia. Also, instead of using cement
in the RCC, fly ash
from the Muja Coal Power Station
was used, which reduced costs and minimised the heat produced during the hardening of the concrete.
Due to the construction methods used, the dam was completed less than a year after excavation began on its foundations, halving the time it would have taken had more conventional methods been employed. The dam was officially opened on 22 November 1991 by Ernie Bridge
, then the Minister for Water Resources.
The new dam supplies water to the Perth Hills suburbs of Kalamunda
and Lesmurdie
, and also supplies the rest of the metropolitan area in times of peak demand. The area is not open to full public access; it can only be visited by the public via walking trails.
Water supply
Water supply is the provision of water by public utilities, commercial organisations, community endeavours or by individuals, usually via a system of pumps and pipes...
dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...
providing water for the city of Perth, Western Australia
Perth, Western Australia
Perth is the capital and largest city of the Australian state of Western Australia and the fourth most populous city in Australia. The Perth metropolitan area has an estimated population of almost 1,700,000....
. It is situated on the Darling Scarp
Darling Scarp
The Darling Scarp, also referred to as the Darling Range or Darling Ranges, is a low escarpment running north-south to the east of the Swan Coastal Plain and Perth, Western Australia...
near Lesmurdie
Lesmurdie, Western Australia
Lesmurdie is a suburb of Perth, Western Australia, located within the Shire of Kalamunda.It is viewed as being a rival suburb to the neighbouring suburb of Kalamunda directly to the north. The main access to the suburb from the Swan Coastal Plain is via Welshpool Road, that snakes its way up the...
, and crosses Munday Brook. Two dams have stood at the present site; the older dam was the first permanent water supply for the colony and also the first dam in Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
.
It stood for almost 100 years before being replaced with the current dam.
Old Victoria Dam (1891–1990)
Prior to the constriction of the dam, residents of Perth sourced their drinking water from wellsWater well
A water well is an excavation or structure created in the ground by digging, driving, boring or drilling to access groundwater in underground aquifers. The well water is drawn by an electric submersible pump, a trash pump, a vertical turbine pump, a handpump or a mechanical pump...
, natural bodies of water and rainwater tanks.
With the growth in the population of Perth and Fremantle
Fremantle, Western Australia
Fremantle is a city in Western Australia, located at the mouth of the Swan River. Fremantle Harbour serves as the port of Perth, the state capital. Fremantle was the first area settled by the Swan River colonists in 1829...
, concerns about water quality, pollution and adequate sewage disposal became widespread. Decades of proposals for sewage disposal and water supply systems followed, coupled with disagreement between the Town Councils and the Colony Government about responsibility for this area. An extensive water supply scheme was eventually compiled by the civil engineers Henry John Saunders and James Barratt in June 1887.
The scheme designed by Saunders and Barratt contained full designs, site surveys and runoff estimates, despite no guarantee of approval or financial incentive. The plan included reticulation for both Perth and Fremantle. In July and August 1887, a Legislative Council Select Committee appointed to examine the proposal passed the issue back to local government. Fremantle refused to participate in the water supply scheme, so following the departure from the Civil Engineering partnership of Barratt, Saunders removed Fremantle from the plan.
The Colony Government passed enabling legislation, and some privately-owned land covering the reservoir was resumed
Eminent domain
Eminent domain , compulsory purchase , resumption/compulsory acquisition , or expropriation is an action of the state to seize a citizen's private property, expropriate property, or seize a citizen's rights in property with due monetary compensation, but without the owner's consent...
.
Construction was completed in 1891. The scheme, which included pipelines to Kings Park
Kings Park, Western Australia
Kings Park is a park located on the western edge of Perth, Western Australia central business district. The park is a mixture of grassed parkland, botanical gardens and natural bushland on Mount Eliza with two thirds of the grounds conserved as native bushland. With panoramic views of the Swan...
and a reservoir there on Mount Eliza
Mount Eliza, Western Australia
Mount Eliza is a hill which overlooks the city of Perth, Western Australia and forms part of Kings Park. It is known as Kaarta gar-up and Mooro Katta in the local Noongar dialect....
, was constructed and operated by the private City of Perth Waterworks Company. The dam became the first permanent water source for Perth.
The concrete dam wall was built using approximately 1,260 tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s of cement
Cement
In the most general sense of the word, a cement is a binder, a substance that sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling modern concrete that was made from crushed...
imported from England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
. The dam wall was a concrete gravity-arch structure, designed in the plan of a large-radius arch. The volume of the concrete in the finished wall was 16,900 cubic metres.
At the time, the catchment area for the reservoir was used for cattle and sheep grazing and also housed several timber mill settlements. As soon after completion as 1892, concerns were raised that this new water source was getting polluted by raw sewage from the timber mills as well as excrement from the livestock.
Several cases of typhoid fever
Typhoid fever
Typhoid fever, also known as Typhoid, is a common worldwide bacterial disease, transmitted by the ingestion of food or water contaminated with the feces of an infected person, which contain the bacterium Salmonella enterica, serovar Typhi...
occurred at a timber mill in the catchment in 1892, at a time when typhoid fever became increasingly prevalent in Perth. Between 1895 and 1900, there were 4047 cases and 425 deaths from typhoid fever in Perth, and the water supply was suspected to be contaminated. In response to this, in 1896 the Colonial Government purchased the scheme, including the dam, pipelines and Mount Eliza reservoir. In 1897, a sample of the water from the reservoir was found to contain the bacteria causing typhoid fever, and strict by-laws were implemented to prosecute any cases of pollution of the water catchment. Also, a channel was cut to divert the Munday Brook water (polluted by the timber mills) away from the reservoir.
The dam as originally constructed featured two small spillway
Spillway
A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. In the UK they may be known as overflow channels. Spillways release floods so that the water does not overtop and damage or even destroy...
s. In 1939, one of these was closed and the other expanded.
Water leaking through the dam wall leached
Leaching (chemical science)
Leaching is the process of extracting minerals from a solid by dissolving them in a liquid, either in nature or through an industrial process. In the chemical processing industry, leaching has a variety of commercial applications, including separation of metal from ore using acid, and sugar from...
lime
Lime (mineral)
Lime is a general term for calcium-containing inorganic materials, in which carbonates, oxides and hydroxides predominate. Strictly speaking, lime is calcium oxide or calcium hydroxide. It is also the name for a single mineral of the CaO composition, occurring very rarely...
from the concrete, weakening the structure. Efforts to reduce the leaking occurred in 1912, and in 1966 the upstream side of the dam wall was covered with reinforced concrete to reduce further leaking. However, a 1988 review of the dam's design concluded that it lacked sufficient safety margins in the event of floods or earthquakes, and its concrete had degraded to such a level that it could not be repaired, and needed replacement.
New Victoria Dam (1991–present)
The decision to replace the Old Victoria Dam was made in 1989. Use of the old dam for water supply ended on 3 April 1990, and the old dam was partially demolished. Construction on the new dam started on 23 August 1990.The new Victoria Dam wall was constructed just upstream from the old dam using roller-compacted concrete
Roller-compacted concrete
Roller-compacted concrete or rolled concrete is a special blend of concrete that has essentially the same ingredients as conventional concrete but in different ratios, and increasingly with partial substitution of fly ash for Portland cement. RCC is a mix of cement/fly ash, water, sand, aggregate...
(RCC), rather than the more traditional method of large concrete pours or earthfill. It was the first dam built in Western Australia using this method, and at the time was the largest of this type built in Australia. Also, instead of using cement
Portland cement
Portland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout...
in the RCC, fly ash
Fly ash
Fly ash is one of the residues generated in combustion, and comprises the fine particles that rise with the flue gases. Ash which does not rise is termed bottom ash. In an industrial context, fly ash usually refers to ash produced during combustion of coal...
from the Muja Coal Power Station
Muja Power Station, Western Australia
Muja Power Station is a power station 22km east of Collie, Western Australia. It has eight coal powered steam turbines that together generate a total capacity of 854 MW of electricity. The coal is mined in the nearby Collie Sub-basin....
was used, which reduced costs and minimised the heat produced during the hardening of the concrete.
Due to the construction methods used, the dam was completed less than a year after excavation began on its foundations, halving the time it would have taken had more conventional methods been employed. The dam was officially opened on 22 November 1991 by Ernie Bridge
Ernie Bridge
Ernest Frances "Ernie" Bridge is an Australian politician and country music singer. He was a member of the Western Australian Legislative Assembly from 1980 to 2001, representing the electorate of Kimberley, first as an Australian Labor Party representative and then as an independent MP...
, then the Minister for Water Resources.
The new dam supplies water to the Perth Hills suburbs of Kalamunda
Kalamunda, Western Australia
-Transport:Kalamunda Road serves as a major access road for Perth Airport, and provides the foothills suburbs with access to the Perth central business district....
and Lesmurdie
Lesmurdie, Western Australia
Lesmurdie is a suburb of Perth, Western Australia, located within the Shire of Kalamunda.It is viewed as being a rival suburb to the neighbouring suburb of Kalamunda directly to the north. The main access to the suburb from the Swan Coastal Plain is via Welshpool Road, that snakes its way up the...
, and also supplies the rest of the metropolitan area in times of peak demand. The area is not open to full public access; it can only be visited by the public via walking trails.
External links
- Dam storage level and statistics
- Structurae: New Victoria Dam (1991)
- Gallery of external and internal dam photographs (includes photographs of information boards)
- Consultant's project page for the dam, including gallery