Challenges for the Sydney Water pipeline is nothing new, as it’s almost century-old history shows
Readers may be aware of the controversy generated by the recent proposal by Northern Beaches Council to build a multi-use pathway from Beacon Hill to St Ives. The route is planned to follow the existing Sydney Water pipeline.
From its earliest days, an adequate water supply for Manly was an issue. Manly Dam was built in 1892 by the NSW Department of Works but was to be operated and paid for by Manly Council.
As the population on the Peninsula outside of Manly grew, the Metropolitan Water Sewerage and Drainage Board took over the dam in 1902 and increased its capacity by raising the wall in 1909, 1914 and 1922.
The coming of the tram to the Peninsula in 1914 led to a rapid increase in both population and water demand and by the mid-1920s an additional source of water was needed. The decision was made to use the Board’s existing Pymble Reservoir which was fed, via a pumping station at Ryde, from the Prospect Reservoir.
Building a 7 mile pipeline through the rocky and undulating terrain from Pymble was a challenge. The decision was made to use relatively short, prefabricated lengths of pipe. To reduce weight for transport, these were built from wood rather than steel, using stave construction, somewhat like a greatly lengthened wine barrel but with parallel sides and no ends. To receive the water a new reservoir was built at Beacon Hill.
It is this nearly 100-year-old pipeline – upgraded to a steel and concrete construction – that the proposed “active transport corridor” is to follow.
Starting up a wooden pipeline was always an interesting event. The sealing of the gaps between the staves relied on the swelling of the wood once it became wet. This took some time and the first hours after start up were no doubt stressful.
Richard Michell is the vice-president of the Manly, Warringah and Pittwater Historical Society and the secretary of Friends of Dee Why Lagoon. Visit mwphs.org.au and fodyl.au respectively.