Causes and impact of urban flooding in dehradun

Disasters like flooding have changed their dimensions in urban areas. The urban flooding in cities is mainly in the form of flash floods and water logging of streets due to high intensity short spell rainfall. But the extents of damage to these disasters have increased over time in the urban areas because of increased rainfall runoff volume and due to greater exposure of people and assets because of concentration of resources. But it is clearly evident that different level of exposure and different extents of flood hazard characteristics vary the ‘urban flood risk’ nature from city to city. In order to be able to quantify the present and potential flood risk, an understanding of the causes of urban flooding, vulnerability and exposure is mandatory. These may be seen as -causing and impacting factors of flood risk, which may be specific to a given area. In this context a study is conducted to identify the reasons of flooding in the city of Dehradun, (the capital of Uttarakhand State), where these factors are studied as- (a) causes of flooding factors and (b) impact due to flooding factors, for Dehradun. River flooding and water logging of streets is one of the major problem of the area during monsoon period. The urban floods in the city causes great amount of destruction and inconvenience; causes heavy traffic jam due to street water logging, paralyzes day to day activities, damage the urban infrastructure viz, roads, bridges, electric poles etc causing severe economic damage. Therefore this evidence based study is taken up, where review of flooding incidents of last 5 years (2009-2013), highlighted the significant factors of causes and impacts of flooding where as primary survey and visual survey has also been conducted which helped in identifying the people’s perception of risk and the experts are also interviewed to get most accurate information.