The job that he is mostly remembered for is the goldfields water pipeline. Gold had been discovered in the Yilgarn region near Southern Cross. Then more even further east near Coolgardie. Then Paddy Hannan made his famous find at Mt Charlotte in what is now Kalgoorlie. And the gold rush started, as wannabe miners streamed to the area from around the world. In no time there were thousands of miners in the area.
But even miners with a thirst for gold have an even greater thirst for water. Without water life stops. And the area around Kalgoorlie there is no water. It is a dry, hot country! Miners were literally dying because of a lack of water. Water was being sold in Kalgoorlie for the equivalent of $30 a litre – more expensive than whisky! And it wasn't particularly clean, either. Sometimes it was infected with typhus, and many died from it. At Kanowna, 12 miles from Kalgoorlie, most of the cemetery was filled with typhoid victims.
Something had to be done, and John Forrest again turned to O'Connor, and O'Connor did not let him down. After extensive research carried out by himself and his staff, including consultation with some of the great engineers of the world when he went London for his investiture, he presented detailed and costed plans for a dam to be built on the Helena River east of Perth, and the water to be pumped 350 miles or 600 kilometres to Kalgoorlie. In the process the water would have to be pumped 1000 feet or about 300 metres uphill.
When it was finished it was the greatest water engineering project in the world. One hundred and five years after the water first flowed from that pipe at the Mt Charlotte reservoir in Kalgoorlie, the pipeline is still the lifeblood of Kalgoorlie and the goldfields, and of many towns near the pipeline on the way from Perth.