Definition
The Karnaphuli Tunnel is a road tunnel located beneath the Karnaphuli River in Chattogram (formerly Chittagong), Bangladesh. It serves as a vehicular passage connecting the city’s northern and southern districts and is the first underwater road tunnel in South Asia.
Overview
Construction of the tunnel began in 2017 as part of Bangladesh’s broader infrastructure development program aimed at easing traffic congestion and promoting economic activity in the Chattogram metropolitan area. The tunnel was officially inaugurated in August 2023. It is a segment of the larger Chattogram–Cox’s Bazar highway project, linking the country's major port city with the tourism hub of Cox’s Bazar. The tunnel provides a direct, weather‑independent route for passenger cars, buses, and light trucks, reducing travel time across the river from an average of 30 minutes to approximately 5 minutes.
Etymology/Origin
The name “Karnaphuli” derives from the Karnaphuli River, which flows through Chattogram and empties into the Bay of Bengal. The river’s name is believed to originate from the Bengali words “karnā” (earring) and “phuli” (flower), though the exact linguistic roots are not definitively documented.
Characteristics
- Length: Approximately 3.4 kilometres (2.1 miles).
- Depth: The tunnel reaches a maximum depth of about 55 metres (180 feet) below the riverbed.
- Lanes: Two traffic lanes (one in each direction) with a total width of roughly 9 metres.
- Construction Method: Utilized the immersed tube tunnel (ITT) technique. Precast concrete sections, each 150 metres long, were floated to the site, submerged, and linked underwater.
- Ventilation and Safety: Equipped with a forced‑ventilation system, fire detection and suppression mechanisms, emergency exits, CCTV monitoring, and a dedicated control centre.
- Operational Management: Managed by the Chattogram City Corporation in coordination with the Bangladesh Roads and Highways Department.
- Cost: The project’s reported cost was around US $350 million, financed primarily through domestic funding and a loan from the Asian Development Bank.
Related Topics
- Karnaphuli River: The major waterway that the tunnel traverses.
- Chattogram–Cox’s Bazar Highway: The larger roadway network of which the tunnel is a component.
- Immersed Tube Tunnel (ITT) Construction: A method used for underwater tunnel building worldwide.
- Infrastructure Development in Bangladesh: Government initiatives aimed at enhancing transport, energy, and communications infrastructure.
- Bangladesh Roads and Highways Department (RHD): The national authority responsible for road planning, construction, and maintenance.