Dhaka-Chattogram 81-km elevated rail line to cost Tk 83,901 cr
Graphics: Agamir Somoy
A high-speed elevated railway is set to be built on flat terrain from Shyampur in Dhaka to Cumilla to cut travel distance between Dhaka and Chattogram.
This will not only cut distance but will also transform the country’s freight transport and commuting scenario. The government has taken a decision in principle to choose an elevated structure for constructing the new cord railway line.
At the same time, the railway will be constructed keeping the provision for running electric trains in the future - so that trains can be operated using electricity. The estimated cost for constructing this nearly 81-kilometer-long railway line has been fixed at Tk 83,901 crore.
However, Prime Minister Tarique Rahman will give the final decision on whether the entire route will be elevated. Therefore, a proposal is being sent to the Prime Minister’s Office from the Ministry of Railways. Even if the entire route is not elevated, it will be 57 kilometers. In that case, the construction cost will come down by Tk 10,000 crore.
The plan to make the entire route elevated was made to reduce land acquisition. Although going for an elevated railway increases the cost by Tk 10,324 crore compared to a conventional railway line.
Before starting the project, a separate project will be taken up for land acquisition. Under this, Bangladesh Railway will acquire about 4,000 acres of land. A decision has been taken to allocate nearly Tk 20,000 crore for land purchase.
After land acquisition is complete, the main project will go to the Executive Committee of the National Economic Council (ECNEC) for approval. And after the start of construction, the timeframe for implementation is estimated at 4 years.
On Monday, various aspects of the project’s feasibility study, design, and technical planning were presented at a stakeholders’ workshop at Rail Bhaban in Dhaka. These details were revealed from information presented at the workshop and project-related documents.
One of the key features of the cord line (short route) is incorporating the provision for future electric train operations into the design right from the start. The required height and clearance of the elevated structure are being determined in such a way that an overhead electric system can be installed in the future.
According to Railway’s plan, this will be a full broad-gauge double track with a 25-ton axle load. The maximum design speed is set at 160 kilometers per hour, and the operational speed at 140 kilometers per hour. Meaning, the corridor is being planned to accommodate future high-speed passenger trains as well as freight trains.
As the Dhaka-Chattogram railway route detours via Tongi and Bhairab, the distance is nearly 320.8 kilometers. Once the cord line is operational, this distance will drop to nearly 240.63 kilometers.
According to Railway calculations, once the cord line opens, travel time on the Dhaka-Chattogram trip could decrease by one and a half to two hours. This journey takes nearly 4 hours 50 minutes on the Suborno Express; the proposed system aims to bring it down to about 3 hours 30 minutes. There is also a proposal to establish five new intermediate stations in the area between Narayanganj and Cumilla: Jalkuri, Sonargaon, Titas, Debidwar, and Burichang.
Bangladesh Railway Additional Director General (Development) Al Fattah Md Masudur Rahman told Agamir Somoy, “If this railway line is built, it will be possible to increase the number of passenger trains here. In the future, this railway line can be connected with Khulna through the Padma Rail Link. As a result, pressure on the existing route will decrease. Freight trains can be increased there. Overall, an alternative corridor is going to be created.”
Elevation to save land, cost rises by Tk 10,000 crore
On the Dhaka-Cumilla cord line, two alternatives - earth embankment and elevated structure - were reviewed to reduce land acquisition complexities and environmental damage. Among these, the plan to make the entire route elevated has been prioritized.
According to documents, constructing the railway line with a mix of earth embankment and elevated structure would have cost nearly Tk 73,577 crore. On the other hand, constructing a fully elevated railway line stands at an estimated cost of nearly Tk 83,901 crore.
Choosing the elevated route incurs an additional cost of nearly Tk 10,324 crore, which is about 14 percent higher.
In return, the land required for the rail corridor will decrease. While constructing an earth embankment would require a corridor about 56 meters wide, under an elevated structure it will drop to about 30 meters. In addition to saving nearly 322 acres of agricultural and residential land from acquisition, it will be possible to avoid cutting down about 1,20,000 trees.
Expressway to stand 13 meters high for rail
One of the most complex coordinations of the cord line has arisen with the proposed Dhaka- Chattogram eight-lane elevated expressway. In the Pirojpur area of Sonargaon, the service road will remain at ground level, above it will be the Railway’s elevated track, and at the highest level will be the expressway proposed by the Roads and Highways Department.
According to the design, to ensure uninterrupted traffic under the railway elevated structure, the height of the expressway must be increased from the planned 17.73 meters to 31.10 meters.
The impact of this change is not limited strictly to the road’s height. The positions of the expressway’s ramps and toll plazas must also be rearranged. As a result, along with constructing a new railway line, changes are also having to be made to the design of existing and planned major road infrastructure.
Along the route of the cord line lie at least five major gas pipelines belonging to GTCL, Titas, and Bakhrabad. Operating pressure in these lines reaches up to nearly 1,000 pounds per square inch (PSI) in certain places.
According to the plan, the elevated railway line must be taken over or alongside these high-pressure gas lines. As a result, ensuring the safety of gas supply during piling and foundation construction of the viaduct has become a major technical challenge.
Taking special design and technical measures in coordination with the relevant gas companies and Petrobangla to ensure safe clearance from gas lines, foundation construction methods, and protection of the existing supply system is under consideration.
9 rivers in 81 km, coordination needed with 3 major projects
The proposed 81.1-kilometer railway line must cross 9 major rivers. Among these are various rivers, including the Shitalakshya, Old Brahmaputra, Meghna, and Gomti. There is a plan to construct eight major truss bridges and several girder bridges over these rivers.
The combined length of these bridges exceeds 4 kilometers. The largest bridge will have to be constructed over the Meghna River, with a length exceeding nearly 2.2 kilometers.
In implementing the Dhaka-Cumilla cord line route, Bangladesh Railway is having to coordinate with several major infrastructures. Among these are the Bangladesh Bridge Authority’s Dhaka East-West Elevated Expressway, the Roads and Highways Department’s Dhaka-Chattogram 8-lane Expressway, and the Power Grid Bangladesh PLC’s high-voltage power transmission lines.
The Dhaka East-West Elevated Expressway will cross the cord line and its spur line at least at three locations. For the safety of electric trains, maintaining a minimum clearance of 8.58 meters is required there.
