Development of Lahore at West Bank of Ravi

Summary

Lahore, second largest city of Pakistan and 30th in the World, situated on the eastern bank of the river Ravi, is in compelling need of expansion across on to the West Bank, due to the pressures of urban growth, national communications grid and proximity to the international borders. The West Bank of the river, however, being a vast low lying flood plain of mud and silt is an unhabitable wasteland. The river Ravi, deprived of its waters most of the year, carries abrupt flood discharges up to 5700 m³/sec in monsoons. The river therefore has to be trained and the land has to be reclaimed. There are numerous examples in the World, where flood affected low plains have successfully been turned into benefitial urban areas. Method has been suggested in this paper to provide a flood protection dike at the West Bank with remodelling of the bed of the channel, providing of reclamation fill behind the dike and construction of associated drainage works. Alignment of the West Bank dike is a dominant cost/benefit effective parameter. An optimisation exercise has been conducted through dynamic programing to arrive at the best alignment of the dike. A positive feasibility has emerged on account of the benefits by the enhancement of the value of land in relation to the costs.