1929 - Upper Yarra Conduits

Upper Valley Conduits
These are vitally important assets in the Melbourne Water supply system, enabling the transfer of water from the Upper Yarra reservoir into the Melbourne metropolitan supply system.

It is predominately a dual pipeline system, comprising the Yarra Silvan Conduit and the Yarra Valley Conduit

Yarra Silvan Conduit (YSC)
The YSC connects the Upper Yarra Aqueduct to Silvan Reservoir. From the aqueduct two penstocks control the flow into each of the YSC mains. At Mt Little Joe, the two mains spill into a holding basin and flow into a single buried tunnel called Mt Little Joe Tunnel. Flow into this holding basin is controlled by two penstocks, one for each main. At the end of the tunnel the flow spills into a second holding basin.

From the holding basin, flow is returned to a duel pipe system through to Silvan Reservoir. The YSC also takes water from two tributaries, as well as the O’Shannassy reservoir. When the YSC is used to provide water supplies to the Upper Yarra townships, these water sources must be turned out, due to variability in water quality.

Yarra Valley Conduit (YVC)
The typical operating strategy for the YVC is for flows to fluctuate throughout the year in response to required storage levels in downstream storage reservoirs (Silvan, Cardinia).

The YVC and YSC all supply water from the Upper Yarra reservoir to Silvan reservoir (See Figure 1). Along the way, unfiltered water is supplied to Warburton, Warburton East, Yarra Junction and Woori Yallock townships in the Upper Yarra Valley. Water to the YSC first travels along the Yarra Silvan aqueduct for 11.4 km, whilst the YVC is an enclosed pipeline for its entire length.

The YVC and YSC travel parallel to each other between Brahams and Lyrebird treatment plants and then separate. The YVC then travels north of Warburton and Yarra Junction, supplying water to the Martyr Rd and Yarra Junction treatment plants, whilst the YSC passes to the south of these towns.

The two mains cross over downstream of Yarra Junction, with the YSC running alongside the Lusatia Park Treatment plant and terminating at the northern end of the Silvan reservoir. The YVC inlet to Silvan is at the southern end of the reservoir.

Readers are invited to refer to these Engineering papers for detailed information about the Upper Yarra Conduits.

http://www.wioa.org.au/conference_papers/05/documents/DanielEllis.pdf

The author 's Photo Album (2012) provides additional information about the Conduits.

http://www.worldisround.com/articles/374274/text.html