Taxpayers are footing a more-than $73,400 nightly bill for detention centre staff to stay in a floating hotel moored off Papua New Guinea's Manus Island, Fairfax can reveal.

Government contracts show the department of immigration will spend more than $13.3 million to temporarily accommodate staff aboard the Bibby Progress, for seven months to May 30.

According to the website of Bibby Maritime, the British company contracted to provide floating accommodation for detention centre staff, the Bibby Progress boasts a large bar, restaurant, gym and roof terrace.

In October, the Department of Immigration and Border Protection listed a contract worth $1.2 million for the lease of the Bibby Progress to accommodate staff from the detention centre between October 31 and May 31. But it added a fresh contract in November worth more than $12 million, also to Bibby Maritime, for providing temporary accommodation for staff. Together, the contracts will provide for the accommodation of up to 310 staff in 159 bedrooms. The company says its ''coastel'' can be used to accommodate workers in remote locations or where existing accommodation is expensive or difficult to find.

But the government may soon need more accommodation. After Tuesday's riots, Immigration Minister Scott Morrison said 100 additional security staff had been placed on standby for deployment to Manus Island, in addition to the 130 extra security staff who had been sent to the island in early February.