It is called Water Bank and with an estimated total cost of $92 million it has the potential to break the bank. But this "shovel ready" project designed to drought-proof Australia's biggest outback city remains in limbo after missing out on funding in this week's federal budget. While Tuesday's budget included more than $1.3 billion for the National Water Grid Fund, the Commonwealth has turned off the tap for Water Bank at this stage. A spokesperson for Water Minister Murray Watt told the ABC the budget was "financially responsible" and showed "spending restraint across all policy areas". Water Bank will be considered in "future budget rounds", the spokesperson said. Western Australia's historic mining centre of Kalgoorlie-Boulder, about 600 kilometres east of Perth, is famous for the discovery of gold in 1893. But water is almost as valuable as gold in a city home to 31,268 people, who rely on a 566km-long, 123-year-old pipeline for their drinking water. Only so much water can be pumped along the pipeline. For decades, the City of Kalgoorlie-Boulder has irrigated public spaces with treated effluent "I have met with the City of Kalgoorlie-Boulder and I understand the needs and the challenges … they have done an excellent job of putting their case forward," he said.The city's application was for $9.5 million from the National Water Grid Fund to progress stage one of Water Bank. It was boosted by the WA government's pledge of $5 million towards stage one at last year's state election. Mr Wilson described the "crucial" project as "shovel ready"