We know it today as The Tank Stream – an underground curiosity – but it was a vital source of life for the First Fleeters, and before them, the First Australians.

Captain Arthur Phillip chose Circular Quay as the birthplace of the new colony, in part because of this freshwater stream running right into the harbour from a swamp at the western end of Hyde Park. Having supplied fresh water and fish to the original Gadigal People for tens of thousands of years, it would serve as the main fresh water supply for the first 40 years of Sydney’s European life.

But by the early 1800s its waters were so polluted that the colonists had stopped drinking from them, and in time it became a sewer, still emptying into the harbour. As the burgeoning city grew up around the stream, it was covered over with sandstone blocks. Today the Tank Stream lies underground, a stormwater channel managed by Sydney Water.

These virtual tours take you into the tank stream, both as it is now, and how Sydney Water believe it would have looked prior to 1788.

Tank Stream - as it may have once looked

Water from the natural creek trickles down the sides of the rocks, earthy brown and red. Surrounded by bush land, McCarrs Creek is an example of what the Tank Stream may have looked like, before European settlers arrived in Australia. Archaeological and historical research tells us the Gadigal people of the Eora nation used the site for resources and food. This activity took time, so we can assume they may have had a camp set up near the stream. A campsite and plentiful food suggest that the original stream may have been a place of importance to the local First Nations people. 

Once the First Fleet arrived, the stream provided a water source for early farming and industry. Ongoing drought had reduced the stream to a trickle. Governor Philip had convict gangs gouge out three storage tanks from the sandstone beside the stream. The tanks gave the stream its name. 

Unfortunately, the Tank Stream was used as a dumping place for sewage and waste from the surrounding houses, business and industry. By 1826 it was abandoned as the cities water supply. 

Sydney Water now manages the Tank Stream stormwater drain as it runs beneath our city, serving as a reminder of the natural waterway that once was.

Tank Stream - as it is today

Underground and surrounded by sandstone, the Tank Stream of today is a reminder of the craftwork of colonial Australians. Now beneath the city streets, the sound of cars and traffic interrupt the soft swish of the water flowing from natural springs, stormwater runoff and pump outs from the basements and carpark surrounding it. 

The Tank Stream is the reason the city of Sydney is where it is today. It has shaped the city we see today through the shape of the landscape and the location of our streets and buildings. Our contemporary urban water cycle has a lot to thank the Tank Stream for!

The current stormwater drain is made up of approximately 11 m of steel pipe, 267 m of concrete pipe, 199 meters of oviform brickwork and 392 m of Sandstone archway. The catchment is 17.5 hectares, only a quarter of what it once was. 

Sydney Water takes responsibility for managing this important part of our city and heritage. It is an active asset, which means it is serving a function to remove rainfall from our streets and quickly and safely to stop flooding. 

Importantly, it has become an iconic part of our city’s heritage and we cant wait to tour this unique and fascinating place again soon.

Sydney Water

Content supplied by Sydney Water



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