Defence confirmed the expenditure to questions on notice from Centre Alliance senator Rex Patrick. The bikes were purchased for Defence employees working on the $50 billion Future Submarines project so they can travel around the Cherbourg shipyard.
General manager submarines Stephen Johnson authorised the purchase of 16 push bikes in Australia, which were designed in the Netherlands and Australia, and assembled in Australia from internationally-sourced components.
The bikes were then airfreighted to France at a cost of $3,164.77. A further three pushbikes were purchased in France.
"The total purchase price for the 19 pushbikes was $14,341.81. The cost of setting-up and servicing the bikes was 580 euros. The requirement for bikes was documented in a business case," Defence said in its response to the question on notice.
The costs of the bikes were first raised in March this year at additional Senate estimates, where the cost of the fridges at the Cherbourg facility also came into question.
The Department purchased refrigerators with lockable compartments that then raised health concerns after food was left in the compartments while travelling.
Defence confirmed that the cost of the high-end fridges came in at over $13,000 but the locks were being removed at no additional cost.
"Outfitting of the Cherbourg facility included the purchase of three large fridges locally procured for use by personnel in the Cherbourg facility at a total cost of $13,750.60," Defence said.
"The fridges included lockable compartments, as is the custom on the shipyard. The doors to the lockable compartments are being removed at no additional cost. The requirement for fridges was identified in the course of designing the facility."
Senator Patrick said earlier this year costs of this nature suggested careless spending is rife within the project and the Department.
"The project is awash with money and people are behaving recklessly," Senator Patrick said.
"These two incidents are relatively small in the big scheme of things, but they come off the back of larger expenditure concerns."
The senator called on the Department of Defence to take greater care in the way it spends taxpayer money in the $50 billion Future Submarine Project after a sequence of questionable spending has been exposed.
Last year, former senator Nick Xenophon revealed that the Future Submarine Project had contracted a "million-dollar man" at $4,500 per day for the period of a year. At a December estimates hearing, the Department of Defence was then forced to confirm to Senator Patrick that an investigation was underway for misappropriation of Commonwealth funds at the Cherbourg facility.
"We're starting to see a litany of careless spending. It's a cause for real concern. The Future Submarine Project is extremely important and must be managed well," Senator Patrick said.