Mount+Grand+-+Dunedin's+water+supply

=MT GRAND TREATMENT STATION=

One day, Rooms 12 and 14 headed off to explore Dunedin's water systems.We were finding out about the collection of water, treatment of water and distribution of water around our city. media type="youtube" key="UtJ-kakaemc" First stop was Mount Grand where we met Derek who works at the plant.

Dunedin's water passes through the Mt. Grand Treatment Station. (picture courtesy of DCC - http://www.cityofdunedin.com)

The water comes to Mount Grand Water Treatment Plant from Deep Strea. It is brown and has lots of tiny bits of dirt and vegetation. Filtering the water would remove the bits but chemicals are needed to remove the yucky brown colour, little critters and bacteria. Derek explained to us that the Dunedin City Council brings in the town water from Silver Stream. It is piped 60km through the Taieri to Mount Grand. It comes from tussock land so it is brown and dirty water. Derek's job at Mount Grand is to help treat our water so that it comes to our taps clean and clear! The most interesting thing we saw at Mount Grand was the FLOCCULATION of the water. Because the area where our water comes from is covered in Tussock and soil, it arrives to the treatment plant very dirty. We saw the Flocculation tanks where aluminium was added. This acts like a magnet, attracting all the dirt and debris still in the water. Then air bubbles push the aluminium, dirt and debris to the surface of the water and into tanks. The clean water flows out for the rest of its treatment. media type="custom" key="1973128"