The Lower Canal - gone but not forgotten

The Lower Canal - gone but not forgotten

Remarkable for its impressive brick aqueduct and very low grade, the Lower Canal connected the new Prospect Reservoir to the city's existing water supply system at Guildford.  Relying on gravity like the Upper Canal, the Lower Canal dropped just 77 centimetres over its 7.7 kilometre length - a grade of 1 in 10,000. It was another remarkable engineering feat for its time. 

The Boothtown aqueduct - built as part of the scheme - allowed the canal to flow across a 225-metre wide valley. Its 22 brick arches, each with a span of nine metres, are still intact today.

After a series of structural failures in the 1890s, in 1907 the aqueduct was replaced with a three-metre wide inverted concrete syphon. Built in the earth bank beside the aqueduct, at the time it was the longest continuous concrete work of its kind in Australia.  The Lower Canal was decommissioned after a pipeline was completed in the 1990s, and the bush reserve surrounding the canal opened to the public in 2003 as a cycleway.

Today, you can walk or cycle along this unique parcel of bushland as it winds through a densely populated area of Western Sydney, and spot many reminders of the ground-breaking Upper Nepean Scheme and its Lower Canal.

The 22 arches of the spectacular Boothtown aqueduct still stand today in Greystanes and is a reminder of the former Lower Canal.


Saturday 06 June
2,117,635 ML
2,596,150 ML
9,451 ML
1,351 ML
-6,227 ML
Saturday 06 June