The 1938 Bradfield Scheme’s basic concept was simple: take the excess river water flowing to the sea in northern Queensland and divert it inland for irrigation. The cost was too great and the technology of tunnelling through mountains was under-developed. Bradfield’s concept may be achievable today by other means. No tunnel is needed and electricity for pumping water is becoming cheaper. (see Prof Ross Garnaut who foresees Australia having the lowest cost electricity in the world in the next 10 years.)
The concept imagined here is subject to engineering, surveying and hydrology validation. A small dam would be built not far below the headwaters of a river emptying into the sea in Queensland. A channel would be built following the contours from the dam to the nearest saddle in the mountains. A second small dam would be built just below the saddle on the seaboard side receiving water from the channel by gravity. A third small dam would be built at the top or just over the saddle. These two dams would be connected by a pipeline and an electric pumping station. From the third dam on the saddle pipelines would connect over the Divide to land and soil suitable for irrigation, sprinkler or drip irrigation, not flood irrigation. Crops and orchards would be irrigated, not cotton.
A hydroelectric facility may be built between the third dam and irrigation area f to generate electricity to pump water from the second to the third dam. The project would become a form of ‘pumped hydro’. Alternatively, renewable energy could come from a large outback solar farm connected by HVDC cable to supply the HVDC network on the east coast and to pump the water a short distance over the divide (almost a syphon).
It may be practical to build a pipeline like the 530km Goldfields Water Supply Scheme from Perth to Kalgoorlie, commissioned in 1903, to take surplus water from the Revised Bradfield Scheme in north Queensland south to the irrigation areas and Murray/Darling Scheme.
The terrain in north Queensland may be more suitable for several such smaller, viable projects than the one large non-viable Bradfield project. Sale of produce and any surplus electricity would help pay for the projects. Many new jobs would be created in north Queensland in construction and intensive farming. These projects would be integral parts of the proposed east coast mega-region and settlement strategy (see “Settlement Strategy”).
The Revised Bradfield concept seems practical, lower cost and productive. It would be worth further investigation as part of the Prime Minister, Scott Morrison’s policies of developing more food production and drought proofing Australia.