History of the water network

The modern, clean and reliable water supply that Wellingtonians enjoy today is a far cry from the drinking water available to Māori and early European immigrants.

Water in short supply

When Wellington became the capital of New Zealand in 1865, the Government began laying the first water mains from springs in Tinakori Road. Before this, people relied on wells, springs, streams and rainfall to meet their water needs. Wellington's population was around 7,460.

In 1871 James Hector reported to the Water Supply Committee that "no water collected from within the crowded part of the city, from either wells or house tops, is safe or proper for human consumption". The Lower Karori Dam was then built as an answer to the city's water problems.

By 1878 the city was experiencing severe water shortages due to rapid population growth and low rainfall.

An investigation into a typhoid outbreak in Wellington, linked poor sewerage and drainage to the spread of the disease.

Wainuiomata River was chosen as an adequate and reliable source for more water.

By 1900 demand was again exceeding supply. Wellington's population had expanded to 49,344. Two new dams were commissioned: the Upper Karori Dam was completed in 1908 and the Morton Dam (Wainuiomata) in 1911.

In 1919 water shortages were again an issue and water from the Orongorongo River was piped to Wainuiomata via a 3.2km tunnel.

Improved water quality

In 1927 the Wellington City and Suburban Water Board was created by an Act of Parliament. Wellington City Council was given access to the Hutt, Akatarawa, Whakatiki and Pakuratahi watersheds. A new scheme to draw water from the Hutt River was proposed but Petone and Lower Hutt councils rejected the idea, withdrew from the Water Board, and developed the artesian (aquifer) supplies they still use today.

By 1943 the Hutt River scheme was developed largely due to Government help. The Kaitoke weir was built and a 56km pipeline connected it to the Lower Karori Reservoir.

By 1953 water-borne diseases had greatly reduced but there were still complaints about water quality. Chlorination plants were built at Wainuiomata, Karori and Kaitoke, and in 1965 fluoride was added to supplies sourced from the Hutt and Wainuiomata Rivers to improve dental health.

When Regional Council arrived

In 1973 the Government required water resources to be managed on a regional basis, and so the Wellington Regional Water Board was formed. In 1980 this gave way to the Wellington Regional Council which assumed responsibility for collecting and treating water for the greater Wellington area.

The Te Marua storage lakes and treatment plant were opened in 1987, and the now redundant Morton Dam was decommissioned a year later due to earthquake risk. In 1992 the Upper Karori Reservoir was closed due to the same concerns.

The Wainuiomata Treatment Plant was opened in 1993. In 1998 the Karori reservoirs, no longer in use as a water supply, were turned into Zealandia - Karori Wildlife Sanctuary. The water in the dams is still kept as a water supply in the case of an emergency.

In 2004 Wellington City Council worked with Hutt City Council to set up Wellington Water (formerly called Capacity), a non-profit organisation which now maintains the water, sewerage and stormwater infrastructure for both councils.