Science is telling us agriculture, if managed properly, can work in a tropical climate.

There is a myth that we can’t grow food in our north. Those peddling this are wrong and often have not set foot north of Gympie.

If they had they would be familiar with Mareeba, the Burdekin, Emerald and Katherine-Mataranka — all vibrant and thriving farming districts.

There have been failures. The Ord, Lakelands and Humpty Doo initially did not meet expectations. But when did the prospect of failure amount to a reason not to try? You wonder how such pessimists ever go on a date.

Ultimately, what gets built is the work of optimists. Back in 1869, John Powell, a US civil war veteran who lost an arm at the Battle of Shiloh, traversed the Colorado River. He wrote a report recommending damming and developing it. Powell disagreed with the perceived wisdom of the times. The view then was that new farming districts should grow based on the Jeffersonian ideal of the small, independent, yeoman farmer. Instead, Powell argued taming such a wild landscape would require large government investment.

It took decades to fulfil Powell’s vision, and it was finally achieved with the construction of the Hoover Dam in the 1930s. As president Franklin Roosevelt remarked at its opening, “I came, I saw and I was conquered.” Our best and brightest scientists at the CSIRO have come down on the Powell side of this debate, at least in regards to northern farming. As CSIRO researchers said in a report on the various attempts to grow food in the north: “All four of the continuing large-scale irrigation schemes have received significant government investment.” The CSIRO has produced a new report outlining the opportunities to harness three northern water catchments: the Mitchell in Queensland, the Darwin in the Northern Territory and the Fitzroy in Western Australia. More than 100 scientists spent 2½ years researching these opportunities. They have applied the latest satellite data, soil testing and dam site analysis to identify the potential of these northern rivers for increased food production.

The report identifies almost 400,000ha of land that could be irrigated across these three catchments if we build the proposed six dams and other off-stream stor­age. That would create 15,000 agricultural jobs and $5 billion in farm output.

To put this in context, Australia irrigates just more than two million hectares of land today. So the proposed investment in these three catchments would increase Australian irrigated agriculture by 20 per cent.

There are other opportunities in the north, too. In central Queensland the Coalition government is building the Rookwood Weir, which could double agricultural production there. We have provided accelerated depreciation for on-farm water infrastructure that will help finance storage in the Flinders River in the Gulf. And state and federal government investment is doubling the size of the Ord. The recent cotton crop there is achieving yields of more than 10 bales a hectare, as good as many fields in eastern Australia.

All of this is being supported by the $600 million the government has already invested in dams and water infrastructure. We also established a $2bn water fund and a $5bn Northern Australian Infrastructure Facility to provide concessional loans to nation-building infrastructure. These funds are there to help us embark on the next great nation-building agenda of harnessing the water of our north.

The defeatist brigade was out in force just hours after the release of the CSIRO’s findings. GetUp, that respected scientific organisation, immediately claimed that dams “wreak havoc on ecosystems”. The Labor Party dismissed the CSIRO’s more than two years of effort as a “thought bubble”.

Labor and the greenies accept the science only when it suits them. The science is telling us that agriculture can work in a tropical climate if we manage it properly.

There is a lot more work to do. The environment must be protected. We must consider the impact on existing industries such as prawn trawling. And, most important, we must gain the agreement and true involvement of Aboriginal Australians.

The people of Northern Australia, including Aboriginal Australians, have a hunger for economic development no different than what has been achieved in southern Australia. Richie Ah Mat, chairman of the Cape York Land Council, described the dams plans as “absolutely fantastic”. We should ignore the myth makers and build our nation.

Matt Canavan is Resources and Northern Australia Minister.