Study on land use policies of khulna structure plan 2000-2020 in the light of climate change induced flood scenario

Abstract

Khulna, the third largest metropolis of Bangladesh has been identified as one of the 15 most vulnerable coastal cities under climate change. Approximately 20% to 25% territory of the country is inundated during the monsoon, which will be exacerbated due to the climate change, especially in the coastal region. Khulna City is home to around 1.3 million people and is within the Khulna Development Authority (KDA) area of which land use structure is consisted of 46% residential, 18% agriculture, 15% industrial, and 5% commercial. The land use pattern here has been substantially influenced by the flow of the Rupsha and Bhairab Rivers. The whole metropolitan area is poorly drained and approximately 2.5m above the mean sea level. Such low elevation of the city is an obstacle to the development of a proper land use plan. Climate change effect especially sea level rise and flooding is being added to this problem and the situation is supposed to be aggravated in the future. The structure plan prepared by Khulna Development Authority (KDA) in 2000 for regulating growth till 2020 considered a number of factors but it did not consider the climate change impacts. Therefore, it is pivotal to analyze the land use plan and policies of KDA development plan in the light of climate change induced flood effects. Flood damage analysis needs to be carried out with the help of Digital Elevation Model of Flood and stage-damage functions using Geographic Information System (GIS) grid-based approach for analyzing the proposed land use plan and policies. This approach is classified further into two namely aggregated land use based and object-oriented (building foot- print). Due to simplification and having lack of available data, aggregated land use based approach has been selected. Flood damage will provide better understating of the future flood risk, which facilitate the decision makers especially KDA in taking the appropriate actions on flood mitigations and preventions, and making any change on the on-going projects or assessing the Structure Plan and development needs of the city as well. Research findings show that the climate change will cause damage to property at different parts of the city depending on land use in 2020. Maximum damage is estimated to commerce sector (1937 million Taka) and next to industrial sector (124 million Taka). Minimum damage is estimated to agricultural sector after residential use. Proposed commercial land uses are recommended to be reviewed for relocation in flood free areas of the city.