The railways in colonial India are generally considered an imperial scheme designed to mobilize capital, raw materials and troops. Their impact has been measured by the macroeconomic performance of India within the general pattern of industrialization, market integration as well as exports and imports. The role of the railways in ecological deterioration has generally been overlooked. This paper, with its focus on what is today Bangladesh, argues that though there were opportunities to expand the railway in harmony with the water regime of the region - as was the case in Britain and continental Europe during the early phases of railway expansion - different forces and agencies contributed to large-scale ecological and consequently agrarian decline in this region. The paper also examines the fraught ways in which the colonial state's differential policies and bureaucracy, transnational investment networks, and "modern" intellectual perception and engineering - charcterized by a vague understanding of local ecological reality - engaged with the ever-changing landscape of the region until the eve of the departure of the British Raj.