Australian intelligence agencies are receiving ''huge volumes'' of ''immensely valuable'' information from the United States including through the controversial PRISM program, Fairfax Media can reveal.
The ''data deluge'' has required the Australian government to build a state-of-the-art secret data storage facility just outside Canberra.
Privately labelled by one official as "the new black vault", the high-security data centre is nearing completion at the HMAS Harman communications base and will support the operations of Australia's signals intelligence agency, the top-secret Australian Signals Directorate (ASD).
The revelations about the PRISM program prompted widespread concern by civil libertarians concerned about its vast size and the lack of requirement to obtain a warrant before hoovering up internet and email data of users of Google, Facebook, Apple and other top technology firms.
Greens senator Scott Ludlam said the government must explain the degree to which ordinary people were being spied on and whether this circumvented Australian privacy protections.
Australian officials describe PRISM and "similar capabilities" in relation to internet service providers in Australia as "an inevitable response to the digital communications revolution".
The $163.5 million HMAS Harman Communications Facility Project includes an extension to the existing Defence Network Operations Centre and a new ''communication/data-room facility".
Because of its complexity and expansion of operational requirements, the project is 80 per cent over its original budget and five years behind schedule, but construction is near completion.
There has been no discussion of the project in Senate estimates committee hearings, and the public reports of Parliament's joint committee on intelligence and security make no reference to it.
Officially the Defence Department will say only that the new facility will provide data storage and processing facilities but has confirmed that "the Australian Signals Directorate (also known as the Defence Signals Directorate) will be one of the Defence entities at the facility".
It is understood the centre will also serve the Defence Intelligence Organisation and the Defence Imagery and Geospatial Organisation.
In underlining the importance of PRISM, Australian officials noted that it had been described in leaked documents as the most prolific contributor to US President Barack Obama's daily intelligence brief.
''Given that the US shares so much with us, it should be no surprise that this reporting is critical to Australian intelligence,'' one official said on condition of anonymity, adding that it included ''what goes into the ONA [Office of National Assessments] briefs for Prime Minister Julia Gillard and the national security committee of cabinet''.
The officials said that Australia contributed to targeting undertaken by US intelligence, including "identification of specific individuals of security concern''.
However, they stressed that the ASD complied with legal requirements and ministerial guidelines that limit reporting in relation to Australians, other than those of specific security or foreign intelligence interest.
They expressed confidence in the US's adherence to similar agreements.
"We are overwhelmingly dependent on intelligence obtained by the NSA and the US intelligence community more broadly," one official said.
Officials cited intelligence relating to North Korea's military threats, information relating to Australian citizens involved in fighting in Syria, missile technology acquisition efforts by Iran and Chinese internal political and economic developments as recent examples of the benefits of Australia's intelligence ties with the US.
US signals intelligence was also described as "absolutely critical" to the diplomatic campaign that won Australia a seat on the UN Security Council.
Attorney-General Mark Dreyfus has refused to say whether US intelligence agencies have shared with Australia information gained through PRISM.
With David Wroe