Using Remote sensing and GIS to survey surface water in Hanoi, Vietnam

Surface water plays a vital role in the living environment. The shrinking surface water area in urban areas is one of the main culprits causing serious environmental problems such as flooding, ecosystem imbalance, etc. In Vietnam, surface water area in the urban center is rapidly declining due to urbanization, especially in the capital - Hanoi, where the urbanization rate is highest. This study examines the mutation in surface water area in several central districts in Hanoi through the period of 1993-2020 using remote sensing images and GIS. The result shows that the surface water area in the research region decreased gradually over the years from 5881.2 hectares to 4328.7 hectares. This parameter dropped more steeply in recently established districts and those adjacencies namely Thanh Tri, Gia Lam, and Dong Anh than in central districts, Hoan Kiem and Hai Ba Trung for instance. Especially, In 2000 and 2007 the rate of reduction was highest. This finding is useful for urban planners, managers, and policymakers involved in Vietnam's sustainable urban development process.