Ross Creek Water Supply
Engineering Work (eg road, bridge, sawmill, dam)
New Zealand’s first major urban water supply, it was built in 1867, and still serves the needs of Dunedin city today. The water is impounded by New Zealand’s oldest surviving large dam, built in 1867. The capacity is for 220 000 cubic metres (50 million gallons) of water and there are 4.4 kilometres of pipeline, most of it through the “main street” of Dunedin.
The dam is an earth dam with a puddle clay core straddling a fairly steep valley. There are stream bypassing channels on both sides. Abstraction is via a fine masonry tower, still in use.
The treatment plant has had chlorination (1950s), microstraining (1971) and fluoridation (1967). In 1990 clarification was added using magnetite as the primary coagulant – the first in New Zealand, and only fourth in the world.
IPENZ “Engineering to 1990” project
This item of New Zealand’s engineering heritage was recognised as part of the IPENZ “Engineering to 1990” project which the Institution organised to help celebrate the country’s sesquicentenary in 1990. A plaque was unveiled to mark the significance of this water supply as part of the development of the nation.
Parts of this place have been recognised by Heritage New Zealand as a Category 1 historic places (List nos.4722 and 4922):
- Ross Creek Valve Tower: New Zealand Heritage List/Rarangi Korero information
- Ross Creek Earth Dam: New Zealand Heritage List/Rarangi Korero information (www.heritage.org.nz).
The Ross Creek Water Supply Reservoir is accessible via a public walking track from Glenleith in Dunedin.
Nature of Engineering
Infrastructure (incl. Road, water, ports)
Lat: -45.8467 Long: 170.4985