The company behind the $4.8 billion Airport Link tunnel, BrisConnections, has gone into administration.
Low traffic levels and debts worth more than the tunnel are behind the company's decision to enter receivership, according to its release to the ASX this afternoon.
BrisConnections entered negotiations to restructure its debt, but on Monday night, the board was told lenders were not prepared to support the proposals.
"The Board of BrisConnections (ASX:BCS) today announced its decision to place the BrisConnections entities into voluntary administration," the statement read.
"As advised in a release to the ASX on 12 November 2012, following an analysis of traffic levels post the introduction of tolls and a review which determined that the enterprise value of BrisConnections may be less than the outstanding debt, the Board and Management entered into negotiations with the group's lenders and other key stakeholders regarding potential reconstruction options."
It has been reported just 45,000 vehicles per week were using the tunnel - 90,000 people less than originally predicted.
Traffic volumes had been steadily in decline since tolls were introduced in August last year, according to BrisConnection's media release.
"The Board and Management conducted an extensive review of the expected future cash flows of the group, based on an analysis of actual traffic numbers which, despite extensive marketing and a phased in toll regime, were lower than originally forecast," it read.
The tunnel will remain open as normal to road-users, with BrisConnections moving to assure people all accounts are still secure and active.