Waitākere Reservoir is a
reservoir
A reservoir (; ) is an enlarged lake behind a dam, usually built to water storage, store fresh water, often doubling for hydroelectric power generation.
Reservoirs are created by controlling a watercourse that drains an existing body of wa ...
on the
Waitakere River in the
Waitākere Ranges
The Waitākere Ranges is a mountain range in New Zealand. Located in West Auckland, New Zealand, West Auckland between metropolitan Auckland and the Tasman Sea, the ranges and its foothills and coasts comprise some of public and private land. ...
, west of
Auckland
Auckland ( ; ) is a large metropolitan city in the North Island of New Zealand. It has an urban population of about It is located in the greater Auckland Region, the area governed by Auckland Council, which includes outlying rural areas and ...
in
New Zealand
New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
. The dam was completed in 1910 and is a concrete
gravity dam
A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation. Gravity dams are designed so that each section of the dam is ...
with a slight curvature. It has a lake area of 25.1 hectares and a capacity of 1.76 million cubic metres. The
dam
A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aqua ...
is accessible from the
Montana Heritage Trail, a bush hike in the region.
History

By the late 19th century, Auckland City was plagued with seasonal water droughts. A number of options were considered to counter this, including the construction of water reservoirs in the Waitākere Ranges. The Waitākere Dam was first of a number of dams in the ranges to counteract this issue. In 1905, a decision was made to dam the
Waitākere River at the location of the Waitākere Falls, then a popular tourist site.
The township of
Swanson
Swanson is a brand of TV dinners, broths, and canned poultry made for the North American and Hong Kong markets. The former Swanson Company was founded in Omaha, Nebraska, where it developed improvements of the frozen dinner. The TV dinner busi ...
was a major source of labour for the project. A tramway was constructed between the Waitākere Falls site and the township, in order to transport supplied from the
Swanson railway station.
By 1907, the
tramline and pipeline tunnels had been completed, connecting the future dam to a reservoir at
Ponsonby.
Thomas Billington & Sons' tender to construct the concrete dam was accepted in May 1907. The concrete foundations began construction in 1908.
The dam project suffered a major setback in May 1910, when a torrential rain caused a landslip upstream of the dam. The landslip caused the dam to burst, flooding the Waitākere River valley and scattering timber and construction tools.
Despite the setback, the gap in the dam was mended, and the dam was completed by December 1910.
Between 1926 and 1928 the dam was raised an additional five metres in height.
During the same period, a filtration station was built at Swanson by a
Dalmatian New Zealander work force.
The filtration station continues to be used today.
The construction of the Waitākere Dam permanently reduced the flow of the Waitākere River, greatly impacting the
Te Kawerau ā Maki
Te Kawerau ā Maki, Te Kawerau a Maki, or Te Kawerau-a-Maki is a Māori ''iwi'' (tribe) of the Auckland Region of New Zealand. Predominantly based in West Auckland (Hikurangi also known as Waitākere), it had 251 registered adult members as of J ...
community at
Te Henga / Bethells Beach. Between the 1910s and 1950s, most members of Te Kawerau ā Maki moved away from their traditional
rohe
The Māori people of New Zealand use the word ' to describe the territory or boundaries of tribes (, although some divide their into several .
Background
In 1793, chief Tuki Te Terenui Whare Pirau who had been brought to Norfolk Island drew ...
in search of employment or community with other Māori.
In 1991, the dam was emptied entirely, so that work could be done to strengthen the dam wall. This was completed in early 1993.
In 1976, the Waitakere Tramline Society was formed, which offered tourist tram rides along the remaining section of the
Waitakere Tramline. This continued until 2014, when the tramline was closed due to safety concerns.
References
{{DEFAULTSORT:Waitakere Reservoir
1910 establishments in New Zealand
1910s architecture in New Zealand
Buildings and structures in the Auckland Region
Lakes of the Auckland Region
Reservoirs in New Zealand
Waitākere Ranges
Waitākere Ranges Local Board Area
West Auckland, New Zealand