Criteria for funding by Waka Kotahi rely on the number of vehicles that use a road, Cameron said, and not on how much saleable product comes out of it.
"It appears now that they're willing to start looking at what product comes out of there. I'm hoping it's going to be a breakthrough," he said.
Whatever happens, both the overbridges will have to be replaced. If Waka Kotahi will not subsidise it the council will borrow the money, Cameron said.
Waka Kotahi director of regional partnerships Emma Speight said that decision will be made in June.
Another possibility for getting product out could be a temporary railway crossing near the bridges. It would be only interim.
"KiwiRail will not be keen to have trucks using it constantly."
If a crossing is put in another will have to be removed somewhere else, and the crossing will take time to construct.
KiwiRail is willing to talk to the Ruapehu council about a solution, executive general manager operations Siva Sivapakkiam said.
"KiwiRail's aim is always to reduce risk on the network, and we are reluctant to add any further level crossings because of the danger of collisions," he said in a statement.
When a new crossing is requested or required, KiwiRail's strong preference is for it to have the road running either above or below the track, by using a bridge or tunnel.
"This reduces the risk of collisions between trains and vehicles at crossings to virtually zero."
Any crossing would have to meet all safety, technical, and railway operational requirements and legal requirements, and it must not constrain the present and future use of the rail corridor for rail.
The council's debt is $33 million. That will balloon to $100 million if it has to borrow to do all the Three Waters work mandated by the Government.
The increase would be "uncomfortable" and mean changing the council's debt limit policy.