Toll road operator Transurban says traffic growth on its main asset, CityLink, in Melbourne, still has not returned to the levels prior to the global financial crisis (GFC).
Transurban on Tuesday booked a net profit of $81.1 million in the six months to December 31, down from $96.6 million in the previous corresponding period.
Net profit attributable to members fell 13.2 per cent to $80.9 million.
Profit before depreciation and amortisation, net finance costs, equity-accounted investments and incomes taxes lifted 7.4 per cent to $340.8 million.
Transurban owns Melbourne's CityLink, and the Hills M2 and Lane Cove Tunnel in Sydney.
It also holds a major stake in Sydney's M1 Eastern Distributor and a 50 per cent interest in Sydney's Westlink M7 and M5 Motorway.
"CityLink does show great resilience (to economic downturn)," Transurban chief executive Scott Charlton told reporters on Tuesday.
"But compared to what the traffic was growing at pre-GFC, it still is subdued."
Mr Charlton said there was still some softness in the economy.
He said the upgraded southern link on the CityLink toll road opened around a year ago and the benefits of that upgrade were still coming through in the traffic numbers.
Transurban said it had submitted an unsolicited proposal to the NSW government prior to Christmas in relation to the F3/M2 connector.
"We're waiting for the government to review that," Mr Charlton said.
Transurban also said on Tuesday that one of its development projects in the United States, the 495 Express Lanes in Virginia, had opened to traffic in November 2012, but initial traffic was below expectations.
Required adjustments to local traffic patterns were expected to take time.
"We're a little disappointed with how it has started, but it's a 75-year concession period, and we expect a significant ramp-up period," Mr Charlton said.
Transurban's toll revenue in the six months to the end of December was $397.7 million, up 3.1 per cent on the prior corresponding period.
Revenue increased due to a rise in the toll for CityLink, which was partially offset by the impact of upgrade work on Sydney's M2.
Transurban said upgrade work on the M2 was 84 per cent complete and was due to be finished in mid-2013.
"We have made good progress on key development projects during the period and are now focused on completing the Hills M2 upgrade so that we can see the full benefit of that project flow through all of our northern Sydney assets," Mr Charlton said.
Transurban declared an interim distribution of 15.5 cents per stapled security, up from 14.5 cents at the same time in the previous year, due to a rise in its cash flow.
The company expects to pay 31 cents per security, partially franked, for the full 2012/13 financial year.
Transurban securities closed six cents, or 0.98 per cent higher at $6.16 on Tuesday.