The first underwater tunnel in Bangladesh and South Asia built by China is expected to be completed this October. Located at the estuary of the Karnaphuli River in the country's second largest city, Chittagong, the tunnel will shorten the travel time for a crossing from one hour to just under 10 minutes.
Bangabandhu Sheikh Mujibur Rahman Tunnel (Karnaphuli Tunnel) is an under—construction underwater expressway tunnel in the port city of Chattogram, Bangladesh under the Karnaphuli river. The length of the entire route is 9.39 kilometres (5.83 mi), with the tunnel making up 3.32 kilometres (2.06 mi) of the length. The tunnel diameter will be 10.80 metres (35.4 ft). The cost of the project is estimated at US$ 1.1B, of which around half is financed by the Exim Bank of China. The tunnel is expected to be completed in 2022 and will be the first river tunnel in South Asia. It is expected to improve the Dhaka—Chittagong—Cox's Bazar highway network. A Chinese company, China Communications Construction Company, was selected to construct it. Prime Minister Sheikh Hasina and Chinese President Xi Jinping inaugurated the construction site of the Karnaphuli Tunnel on 14 October 2017. On 24 February 2019, Sheikh Hasina also inaugurated the tunnel boring phase.
The multilane tunnel route will pass through the river close to Navy College on one side and Korean Export Processing Zone (KEPZ) and Karnaphuli Fertiliser Company (KAFCO) on the other. It will connect Chittagong port and Anwara upazila and is expected to make communication between Chattogram and Cox's Bazar easier. It will also ease traffic congestion on two bridges over the Karnaphuli River.