Owhango Water Supply

The Owhango Water Supply System provides potable water to approximately 141 properties within the Owhango township and a number of rural properties in the surrounding area.

Where does my water come from?

Water for the supply of Owhango is taken from a tributary of the Whakapapa River in the Tongariro State Forest known as Deep Creek (see figure below).


Is my water treated?

Yes. Water is gravity piped 3.5km to the Owhango Water Treatment Plant where it undergoes the following processes:

  1. Sediment Settling
    Raw water from the pipeline is passed into a 22.5m3 concrete settling tank.  Smaller, unwanted particles such as sand and dirt settle to the bottom and therefore are removed from the water.

  2. Coarse Screen
    Removes larger sticks, stones and other debri from the water via sieves.  When the storage reservoir is full untreated water overflows onto the farm paddock at this point and flows into the Kakahi Stream (tributary to the Whakapapa River).

  3. Chlorine Dosing
    From the settling tank, raw water gravitates to the adjacent Water Treatment Plant building where it is dosed with low levels of chlorine to kill off comtaminants (bugs) within the reservoirs and pipes into town.

Water monitoring

Online monitoring through System Control and Data Acquisition (SCADA) provides information about the water treatment, such as chlorine. This system checks that water parameters stay within set values for 24 hours every day and will alert the Plant Operator if anything changes.

Where is my water stored?

Chlorinated water is stored in the adjacent 250m3 timber tank reservoir. The flow of water into the reservoir is matched against demand as the plant supply cannot be turned off.

Additional storage from two concrete reservoirs of total volume 48m3 exists within the network. Rural connections are required to have an additional 24 hours storage for their property.


Our pipelines

Treated water is  piped from the storage reservoir to Owhango township and surrounding rural properties. The Owhango Water Supply reticulation network consists of 30km pipeline.  The entire network is gravity supplied. Most pipes are 32mm and 50mm in diameter and are made of plastic (uPVC).  Rural properties are metered.

Flow through the scheme is shown in the figure below.


Page reviewed: 24 Feb 2016 11:19am