Almost five years after the Arnhem Land community of Galiwin'ku was battered by Cyclone Lam, the NT Government is yet to spend $20.3 million of disaster relief funding for rebuilding housing.

Key points: 80 houses in Galiwin'ku were destroyed when Cyclone Lam hit the Arnhem Land coast in 2015

80 houses in Galiwin'ku were destroyed when Cyclone Lam hit the Arnhem Land coast in 2015 $20 million allocated to rebuild houses in Galiwin'ku remains unspent by the NT Government

$20 million allocated to rebuild houses in Galiwin'ku remains unspent by the NT Government The NT Government has missed deadlines to claim Commonwealth reimbursements for the program.

Eighty homes in Galiwin'ku were destroyed and hundreds of people were displaced when Cyclone Lam hit Elcho Island, off the Arnhem Land coast, in February 2015. The less severe Cyclone Nathan followed about a month later.

More than four-and-a-half years on, some people in Galiwin'ku are still waiting for permanent homes.

Long-term resident Oscar Datjarranga, a member of Galiwin'ku's local housing advisory group, said he wanted to know why some people in the community were still living in the "temporary" demountable homes that were brought over in 2015.

"It's not really good because some of the people have been waiting for what, three, four, nearly five years now," he said.

"You know, living in the accommodation that's been provided by the government, they're waiting for the houses to be built."

Oscar Datjarranga is worried the Government hasn't spent the money it was supposed to. ( Supplied: Oscar Datjarranga )

Multi-million-dollar underspend of disaster relief money

In a statement, the Northern Territory Department of Housing said 80 houses in Galiwin'ku were destroyed by the cyclones and needed to be rebuilt.

The 2015-16 Budget Papers allocated $62.5 million to rebuild community housing affected by Cyclones Lam and Nathan in 2015.

From this money, the Department of Housing said $38.5 million had been spent in emergency repairs in Galiwin'ku contributing to the construction of 33 houses.

Nine of the 33 new homes were completed just a few weeks ago.

Galiwin'ku resident Larry Gayula outside his home damaged during Cyclone Lam in 2015. ( ABC Darwin: Emilia Terzon )

An extra $3.7 million went towards works in other Arnhem Land communities including Ramingining, Milingimbi and Laynhapuy homelands.

But $20.3 million — more than a third of the $62.5 million budget allocation — still hasn't been spent.

Oscar Datjarranga said it was important the remaining $20 million was delivered to the community.

"It's supposed to be for Aboriginal communities — we just want to know where the money went," he said.

Debt-laden NT Government misses deadlines for federal reimbursements

The office of NT Housing Minister Gerry McCarthy said the remaining $20.3 million would cover "outstanding expenditure for works completed, as well as the repurposing of transitional accommodation and additional works yet to be identified."

Cyclone Lam destroyed hundreds of houses in Galiwin'ku. ( Supplied: David Collins )

But even if the NT Government spends that $20.3 million, it's unclear if it will be able to claim reimbursements from the Federal Government.

Under a Commonwealth program called the National Disaster Relief and Recovery Arrangements (NDRRA), the NT government was eligible for reimbursement for disaster relief spending following Cyclone Lam.

But in a statement, the NT Government, which is struggling with rising debt, acknowledged time had run out to claim the federal reimbursements.

The NT government had already applied for two 12-month extensions from the NDDRA scheme. The most recent extension expired on June 30 this year.

Students from Shepherdson College complete work experience on Galiwin'ku. ( ABC News: Kate Ashton )

The Department of Home Affairs confirmed the $20.3 million unspent would not be eligible for NDDRA reimbursement unless the Northern Territory government wrote to the Commonwealth requesting a further extension.

Mr McCarthy declined an interview request.

In a statement, his office acknowledged problems with overcrowding and that some people were still living in demountable homes, but said that 23 new homes were proposed in Galiwin'ku.

The NT Department of Housing, Community and Local Government said a total of 90 homes had been built since the cyclones in 2015 through a variety of different programs including the National Partnership on Remote Housing agreement, another stream where the NT government has been accused of underspending.