Busbys Bore Commemorative Cairn, completed in 1988 to commemorate the location of the Busbys Bore.
Busbys Bore was the first major infrastructure tunnel to be built in Sydney that conveyed water to the city from Lachlan Swamp (where Centennial Park now stands) in the early 1800s. The tunnel was excavated by hand, mostly through solid rock, using convict labour. It stretched over a distance of 3.6 kilometres under the city and varied from 1.2 to 1.8 metres wide and up to 3 metres high in places.
As Sydney’s population grew in the 1820s, its initial source of fresh water, the Tank Stream, could not meet demand as well as becoming severely polluted.
In 1824, Civil Engineer John Busby was commissioned by Governor Darling to design this new water system. Busby recommended Lachlan Swamp as the site as it was a low-lying marsh with a plentiful supply of fresh clean water "free from every taste and smell, and so soft as to be fit for every purpose".
Hopes were high for the Colony to have a new clean water supply within a few years, but this was not to be.
The project started off in a flurry of anticipation and activity but the Colony’s excitement started to wear off as the days turned into months, months turned into years. In the end the project took 10 years to complete!
Difficulties with the rock strata and the use of unskilled workers caused problems for the project. It was also said that Busby was reluctant to deal with the convict workers and was a poor supervisor due to his hesitation to go down into the tunnel! Even Busby’s two sons William and Alexander who assisted their father also were said to have remained above ground throughout the project.
From 1830 water was flowing in the tunnel and although it wasn't finally completed until 1837, the Lachlan Swamp served as Sydney’s main water supply until 1859 when a combination of the growth of industry, poor maintenance, livestock grazing and garbage dumping gradually polluted the Swamps.
In 1837, as Sydney’s population grew so did the demand for water. Busbys Bore was supplemented and later supplanted by water pumped from Botany Swamps. In 1934, part of the Bore under Oxford Street was filled with sand to remove the risk of subsidence under the tram lines.
The Bore remains under the ownership of Sydney Water.
-- words from the Sydney Water brochure: Busbys Bore.
The cairn is made of sandstone with three bronze plaques. One reads: 'Centenary of the Water Board – unveiled 23rd September, 1988. The last shaft site in a sequence of shafts and tunnels is located adjacent to mark at the fence.'
The cairn itself is situated on Grand Drive, Centennial Park approximately 100 metres east of Robertson Road Gates.