by The location of Sydney was determined by the Tank Stream: a rivulet that was the colony’s first water source, and that still exists today, underground.
When the First Fleet arrived in Australia in January 1788, they had difficulty determining a location for their settlement.
Nearly twenty years earlier, Captain James Cook had sailed past what would become New South Wales, and provided a glowing report on a harbour he called ‘Botany Bay’. Based on this account, this was the First Fleet’s original destination.
Their voyage to Australia had been an epic undertaking. Eleven vessels containing 1 500 people – transported convicts, soldiers, and settlers – crossing 24 000 km of ocean from England.
But after such a lengthy trip, Botany Bay was a disappointment. The fleet arrived on 18 – 20 January, and found the area ill-suited to their purpose: the harbour was shallow, the land adjacent open to the elements, and lacking fresh water.
Commander of the fleet Arthur Phillip quickly determined that a new location would be required. On the 21st of January he set out with a party in three small boats, to explore other harbours nearby.
12 kilometres to the north, they found Port Jackson, which Cook had passed but not entered. Phillip was delighted to discover this was an ideal location; the new harbour was protected, deep, and supplied with freshwater.
He would later describe it as, ‘the best harbour in the world’.
Phillip returned to Botany Bay and gave the order to decamp north. The fleet would arrive in Port Jackson on January 26, 1788.
Phillip chose for the settlement a flat area a distance into the harbour, away from the turbulence of the heads, further sheltered by a jutting point. One of its key attractions was a small stream, providing fresh water.
Captain Watkin Tench would provide the first description of the stream in his diary.
‘Into the head of the cove, on which our establishment is fixed, runs a small stream of fresh water, which serves to divide the adjacent country to a little distance, to the north and south.’
The fleet landed nearby and began unloading their passengers and cargo.
Phillip would name the location ‘Sydney Cove’, after Thomas Townsend, 1st Viscount Sydney. Townsend was then Home Secretary in the British Government, and so responsible for the transportation of prisoners; he had also appointed Phillip to his position.
As the settlement slowly began to establish itself, the new arrivals explored the surrounding area.
It is difficult to imagine what this must have been like. The isolation of Sydney was acute; the nearest substantial European settlement, Batavia, was some 3 500km away, and under control of the rival Dutch.
The environment was full of exotic plants and animals, many previously unknown.
There were also people. The settlers would encounter the local Indigenous population, the Eora people of the Bidjigal clan, having had some contact with the Gadigal tribe at Botany Bay.
These first encounters were friendly, and Phillip had orders to try and establish a good relationship with the native population. But the two sides mostly kept a polite distance at first, with the Indigenous tribes largely avoiding the new settlement.
As Phillip’s men explored their surroundings, they discovered the source of the stream. It ran directly inland from the harbour for a few kilometres, and could be traced back to a swampy area around what is now Hyde Park.
‘The stream dropped about 30 metres through a series of waterfalls to Bridge Street, where it met the harbour. Draining about 82 hectares, it was supplemented by springs in what is now King Street, and Spring Street.’
– Sydney Water
Recognising the importance of keeping his water source clean, Phillip decreed a green belt around it. For 15 metres either side of the stream, development was prohibited: houses and other structures could not be built, livestock and commercial use was barred.
A fence was erected in some parts, to control access to the water.
The first years in Sydney Cove were very tough. In Robert Hughes’ book ‘The Fatal Shore’, he calls them, ‘the starvation years’.
One aspect the Europeans had to adjust to was the climate, which was harsher and more volatile than they were used to.
The winter of 1788 saw torrential rain, which caused the freshwater stream to swell and burst its banks. Several buildings were washed away, the town’s roads were turned into a muddy bog.
The following summer brought baking temperatures and eventual drought, and the stream dwindled to almost nothing. This lead to the settlement’s crops failing; the cause of the hunger Hughes alluded to.
While the stream provided a reasonable amount of water during normal conditions, Phillip worried about future shortfalls. With this in mind he instigated a programme of works, designed to increase supply; his convict workers set to deepening and widening the stream.
In the sandstone banks they also carved out five stone hollows, which were referred to as ‘tanks’; each tank was five metres deep, and could hold about 20 000 litres of water. When the stream was flowing the tanks would fill naturally, the water could then be used at a later time.
While this did provide some water security for the town, it was an imperfect system. The tanks would also collect silt and debris, and as the water sat stagnant it could harbour disease.
Sydney’s inhabitants complained of the poor quality, and taste, of the water coming from what they now called, ‘The Tank Stream’ (the original, Indigenous name for the stream is no longer known).
Phillip was a highly capable leader, but the harshness of the environment took a toll on his health. After four difficult years, he was recalled to England for medical reasons in 1792.
Control of the colony then transferred to the military’s New South Wales Corps, under its ranking officer, Major Francis Grose.
Grose was an affable, diffident personality, shy of conflict; under his charge many restrictions in the colony were relaxed. This impacted the Tank Stream, where the protected area around the water was no longer enforced.
Houses and pigsties were built along the stream’s edge, many by soldiers, with significant pollution then entering the water.
By the time Captain Phillip King was appointed Governor in 1800, the stream was much degraded.
But as it was still used for drinking water, King tried to restore the water quality through regulations; new buildings along the banks were again banned, some existing structures were demolished. Trenches were dug on either side, to try and prevent run off reaching the water, a bridge was built across its mouth.
King also instituted harsh penalties for polluting the stream, including flogging.
While these measures had some success, they were really just prolonging the inevitable. Sydney was a city on the grow, the settlement was leaving a larger mark on the natural environment.
By the late 1820s, the population was more than 10 000, and the Tank Stream had become little more than an open sewer. This and other small streams were used for dumping effluent and other waste, which then flowed untreated into Sydney Harbour.
As the Tank Stream became unusable, there were frequent shortages of drinking water. People began to source their water from wells, the government also had water shipped in from springs in the surrounding countryside.
In 1827, the government developed a new fresh water source at Busby’s Bore, in Surry Hills. A tunnel ran from there to Hyde Park, delivering water into the city centre.
This solved the city’s freshwater problem, with the consequence of sealing the Tank Stream’s fate. From unofficial sewer, it became a designated one.
‘The stream is in effect the main sewer of a large portion of the town. It becomes the channel of conveyance of hundreds of tons of sand, and to a contribution of every species of filth from the rear of the premises abutting upon it.’
– The Australasian, 1836
People living nearby would complain of the smell, and the stream was seen as fostering waterborne diseases.
By the 1850s, the city had grown to a population of more than 50 000, and the government recognised work was needed on its waste disposal system.
Along with other improvements to the sewage network, the Tank Stream was enclosed in a pipe under Pitt Street, and the ground above gradually sealed over. The swamp feeding it was drained as well, to improve the land around Hyde Park.
By 1870, the stream was covered over completely. Largely forgotten it would continue to flow, stealthily, under the growing city.
In 1988, as part of Australia’s bicentennial celebration, Sydney Water restoredthe Tank Stream and certain sections were opened for guided tours.
While this was viewed as an unusual idea at the time, it proved to be very popular; the tours quickly booked out. Since then, interest in the Tank Stream has only increased.
Modern cities have a wealth of hidden spaces underneath them. As they evolve, they usually grow upward; burying areas that were previously on the surface, consigning them to a subterranean existence.
There are also many purpose-built underground spaces like tunnels, service corridors, and drains.
Into the 1990s and beyond, these became of increasing interest to a new kind of urban adventurer. A growing number of people would explore these underground spaces, legally or illegally, the more difficult to access the better.
Sydney is particularly well suited to this activity. There are ghost platforms at Central Station, an underground lake at St James station (read more about this here), abandoned military stores, and a fabled drain that runs under Sydney Harbour between the Opera House and Circular Quay.
You can find photos and descriptions of people trying to access these places online.
The Tank Stream has become one of the most sought-after of these underground destinations, a nice twist in the history of a waterway that had been ruined, and then forgotten. In a new form, it is back.
For those that wish to access it legally, Sydney Water and Sydney Open House sometimes run tours. Due to heavy demand, access is only ever by ballot.
