BEIJING -- Fixed asset investment on China's transport infrastructure, including roads, railways, airports and waterways, are expected to hit 2.5 trillion yuan ($409 billion) this year, Minister of Transport Yang Chuantang said on Sunday.

Transport authorities have played an important role in the nation's efforts to stabilize economic growth by speeding up investment on infrastructure construction, Yang said at a national transport work conference held in Beijing.

Yang said the investment this year is expected to increase roads by 93,800 kilometers, including 7,450 km expressways. Meanwhile, 230,000 km countryside roads are to be renovated in the year.

Total investment on railways are to hit 800 billion yuan this year, which has increased railway mileage by 8,000 km, Yang said.

Eight new airports have been built, while 631 berths are built or reinforced with the investment this year.

Yang predicted that the total passenger and freight volumes via the nation's transport system including roads, railways, airports and waterways will increase 3.7 percent and 7.2 percent year on year, respectively.