Bangladesh Bridge PromiseTransformations Economic

Bangladesh Bridge PromiseTransformations Economic Bangladesh Bridge PromiseTransformations Economic The bridge is at least three years away but it has already caused a stir in Bangladesh. Scheduled to be completed in 2014, the 6.15 km-long Padma Bridge, the longest in South Asia, is expected to transform the countrys economically depressed southwest zone by connecting it to the capital city of Dhaka and other relatively developed regions.At least 30 mio people, almost one-fifth of the countrys total population, will directly benefit from the bridge, according to a study by the World Bank.The mega-project, costing nearly $3 billion, has become a reality after the World Bank formally announced its contribution of $1.2 billion on Jan. 13, 2011. In addition, the Asian Development Bank has committed $615 million Japan 400 million the Islamic Development Bank $140 million. The remainder will be paid by the Bangladesh government.The Padma river has a tendency to change course.The ProjectThe proposed bridge is the largest infrastructure project ever undertaken in the country. It is a multipurpose fixed crossing over the Padma River with provisions for a rail line, gas pipeline, fiber-optic cable, and power transmission lines.The two-level steel truss bridge will carry a four-lane highway on the upper level and a single track railway on a lower level.The bridge lies on the Dhaka-Kolkata (India) link and will form an integral part of the Asian Highway and Euro-Asian Railway network systems.Once the bridge is built, travel between the southern districts and Dhaka will be cut by 100 km, benefiting not only the relatively undeveloped southwestern region, but the country as a whole.The project consists of a double-deck, steel-truss bridge with a four-lane, divided highway on the top deck and a single track rail on the bottom deck. The bridge will have two toll plazas and a 12-km-long, four-lane approach road on the southern side with service areas for construction management and tourism in the postconstruction phase.Technological ChallengesJamilur Reza Choudhury is the chairman of theInternational Panel of Experts, Padma Bridge Project, and former professor of civil engineering, BUET. As Bangladeshs foremost expert on the bridge project, he says the construction will involve two major technological challenges.The first is in the bridges foundation. According to Choudhury, the structure will have the deepest piles used in bridge foundations anywhere in the world. These very large diameter, tubular steel piles inclined from the vertical will have to be driven to depths of 115 m. So the contractors will have to mobilize the heaviest pile-driving hammers ever used. The best known manufacturer of such hammers is in Germany and they are used in construction of offshore oil platforms.The second is in river training. Builders must ensure that river water continues to flow under the bridge and that the approach roads leading to the bridge are not attacked by ou tflanking channels.The Padma River (which carries the combined flow of the Ganges and the Brahmaputra) has a tendency to change course, with bank lines moving up to 1 km in a year. Designers must ensure the banks remain stable and do not erode from the alignment existing at the beginning of the construction. This will require dredging up to a depth of 30 m and laying a stone mattress consisting of very heavy rocks.The other challenging aspect is the depth of scour,the depth to which the riverbed can be eroded. It can be as high as 50 m. This means that the foundations and the river training works must be designed to continue functioning even after deep scours take place.The volume of water passing under the bridge could be as high as 140,000 cubic meters per second, making it one of the highest in the world. The bridges length of 6.15 kmwas neededto allow this volume of water to pass under the bridge.Socio-Economic ImpactThe social, economic, and industrial underdevelopment of the s outhwest zonewhich encompasses Bangladeshs second major port, Mongla, its third major city, Khulna, and the inland port at Benapole bordering Indiais due in part to difficult access across the Padma River to the rest of the country.The bridge is expected to have a profound impact on the 30 million-plus people living in the southwest and accelerate economic growth in the country as a whole, according to the World Bank.At the same time, it is expected to raise Bangladeshs GDP by 1.2%, pushing it over 7% and thus, enabling it to become a middle-income country by World Bank standards, with over $1,000 per capita income by 2020.A total of 73,329 people will be affected by the construction of the bridge. The government has already allocated $30 million for their rehabilitation.Communications Minister Syed Abul Hossain hopes construction work will begin in early March 2012, shortly after the selection of the contractor through international bidding.Arshad Mahmud is an independent writer.At least 30 million people, almost one-fifth of the countrys total population, will directly benefit from the bridge, according to a study by the World Bank.