Frontline contractors are abandoning the mining sector in Queensland amid growing doubts that Adani’s huge Carmichael coal project will emerge to deliver them from a savage industry downturn.

Earthmoving businesses that banked on sharing in as much as $2bn worth of work from Adani’s proposed mine, port and rail project are turning to housing, farming and infrastructure projects to survive, industry figures say.

Sally McPherson, the co-founder of the plant hire aggregator iSeekPlant, said that shift had accelerated amid fresh uncertainty around the central Queensland mine, with the federal court overturning commonwealth approval and Adani axing key engineering contractors, its project management team and advisory banks.

McPherson, whose business has 70,000 customers a month, said there was “still absolutely no substitute for the amount of investment and sheer earthmoving that Adani would have been”.

But she said those in the industry tied to mining had either seen the writing on the wall or were going to the wall – now at a rate of several a week in central Queensland alone.

While Adani says it remains committed to the mine and is focused on obtaining government approvals it blames for delaying the project, McPherson said no one in earthmoving was “sitting with the lights off, waiting for [Carmichael] to happen”.

“What you have essentially is a group of companies who really invested hard in the boom and they bought a lot of big machines,” she said.

“What we’re going through now is this enormous structural headache of all the people with the 777 dump trucks and substantial debt portfolios needing to refocus and shift or what we’re going to see is just enormous consolidation, people going broke all over the joint.

“It’s not a structural change you can put your business through overnight – you can’t just trade in your 777s and buy a bunch of backhoes, it doesn’t work like that. But the ones that are surviving – and we’re talking about surviving, no one’s flourishing – are doing it.”

A plant hire business owner, Steve Pollard, said he had realised it was time to move away from mining while working on a coal project near Moranbah in about 2013.

“She was good,” he said of the mining work, which more than doubled the size of his business.

“But during that project you could see mines shutting down pretty quickly. You’d hear of a mine shutting down every month, so you sort of knew the writing was on the wall, that the little mining boom was going to end.

“It wasn’t a real hard decision, mate, it was either that or go broke.”

Pollard said a lot of earthmovers were “hanging” for Carmichael to go ahead as it was the only new mine on the horizon and the opportunities in other sectors were less attractive.

“It’s very hard now,” he said. “But you don’t have a choice. If you don’t do it, you go bankrupt.”