Two more tunnels will be built beneath the Yangtze River, China's longest, the government in Hubei Province said on Monday.
The first tunnel was completed and opened to traffic on Sunday, when it was used by 28,000 vehicles.
The second tunnel, on which work will soon start, will be part of the No. 2 subway line and will be 1,000 meters upstream of the first tunnel.
The third tunnel, whose route is still under discussion, would divert traffic from the Wuhan Yangtze River Bridge, the first bridge on the river.
The bridge, a dual highway-rail facility, and the No. 2 Yangtze River Highway Bridge carry 98,000 and 138,000 vehicles daily, far in excess of their designed capacities.