By the 1850s, gold was all the rage across the newly-declared colony of Victoria and nowhere more so than in Ballarat and surrounds. Prospectors flocked to the goldfields, hopeful of making their fortune working the shallow deposits of alluvial gold which seemed to exist in such abundance.
By the 1870s however, most of the shallow leads had been worked out and gold was becoming harder to find and more expensive to mine. As a result, this decade saw the arrival of the big mining companies chasing deep leads and quartz reefs. On the low lands to the south of Ballarat, this was especially true. Alluvial gold was there to be found, but much of it lay deep in the ground under a layer of hard basalt, which had flowed from surrounding volcanoes, filling ancient creeks and riverbeds where equally ancient alluvial deposits had formed millions of years earlier. Also beneath the basalt lay the quartz reefs, the products of even earlier volcanic events.
As the mining companies moved in, they brought with them their blasting equipment, crushing batteries, water pumps and the steam engines required to power them all.
|Looking across the Sebastopol workings|
Steam-driven pumps were often used to drain shafts however they were expensive to operate, requiring a constant supply of fuel to keep the engines running. As a general rule, it was only the big mining companies which could afford such equipment and this was true of the area to the south of Ballarat where even today, the names of the towns reflect those of the mines which operated in the area - names such as Napoleons, Durham Lead, Enfield, Grenville and Scotchman's Lead.
|Illustration and cross-section view of the Pioneer Gold Mining Company's|
mine a little to the south of today's Durham Lead township and the same
distance east of the Leigh. Image held by the State Library of Victoria.
Click to enlarge
The report was produced by the geological surveyor Reginald A. F. Murray who noted that the watershed of the Leigh River above the Perseverance Mine (previously the Chryseis mine situated near the Leigh about 2km north east of the modern township of Grenville) covered an area of around 200 square miles (518 square kilometres) which he claimed equated to a daily subterranean "percolation" of around 95 million gallons (approximately 360 megalitres) of water through the plateau. But how to drain it?
|Map showing Ballarat and Sebastopol mining claims on the upper|
section of the plateau. Image held by the State Library of Victoria.
Click to enlarge
|Map which accompanied Murray's report, showing the proposed line of the first section of the adit.|
Image held by the State Library of Victoria. Click to enlarge.
Many opinions were put forward for and against each option. There were those who felt that whilst cheaper, the pumps would not provide adequate drainage, whilst others suggested that Murray's estimates fell far short of what would be the true cost of constructing the adit. It was also suggested that to use only a system of adits would require around 19 miles, 10 chains of tunnel with a further 15 miles of tributary adits requiring the sinking of 38 shafts - quite a different story to Murray's proposal and significantly more expensive! Even then, the financial returns suggested by Murray were by no means guaranteed and nor was the drainage itself, it was claimed.
By November, 1889, the issue formed part of a broader royal commission into gold mining in Victoria with the same claims and counter claims about the efficacy of the suggested processes being put forward and some witnesses even claiming that there was little gold left in the area anyway.
Once again it seems no decision was reached and in 1901, 1902, 1903 and in 1905 attempts were still being made to secure government funding for some form of drainage, this time however with the added twist that "by his [the mining engineer's] scheme the adit would serve as a main sewer for the deep drainage of Ballarat and also allow for increasing the water supply."
Again, no definite action was taken although government grants were provided in some cases for private companies.
Then, finally in 1935, the media was abuzz with the news that the plan to construct a "20 mile" adit to drain the plateau had once again been proposed. This time a London company was prepared to spend what was now estimated as being the £1,000,000 required to complete the work which, the papers noted, had lapsed for the last 70 years owing to the expense. However, despite media declarations that drainage was imminent, there is no further mention of such a scheme past this time.
The plateau, it seems, was not drained, the adit was not constructed and the flow of water into the Leigh River was not changed as a consequence of such action, although it is interesting to speculate what the environmental effect of such a plan might have been.