Waitakere Ranges

In the Waitakere Ranges there are three concrete and two earth dams: Upper Nihotupu, Upper Huia and Waitakere dams are concrete while Lower Huia and Lower Nihotupu are earth dams. They were constructed from 1907 to 1971 and named after the streams that feeds into their reservoirs.

These dams supply around 26% of Auckland's bulk water.

	Waitakere Dam Completed: 1910 Lake area: 25.1 hectares Capacity: 1.76 million cubic metres
	Upper Nihotupu Dam Completed: 1923 Lake area: 12.5 hectares Capacity: 2.2 million cubic metres
	Lower Nihotupu Dam Completed: 1948 Lake area:52.9 hectares Capacity: 4.6 million cubic metres
	Upper Huia Dam Completed: 1929 Lake area: 18.9 hectares Capacity: 2.2 million cubic metres
	Lower Huia Dam Completed: 1971 Lake area: 50.3 hectares Capacity: 6.4 million cubic metres

Raw water from the five dams is treated at the Huia, Huia Village and Waitakere treatment plants, located at Titirangi, Huia and Swanson. Water is fed in pipelines both from the dams and into Auckland. The Huia Village Water Treatment Plant supplies water only to local Huia residents.

Huia Water Treatment Plant can produce 107,000 cubic metres of drinking water a day, Waitakere 16,500 cubic metres and Huia Village 275 cubic metres.