High Resolution 1:10,000 scale Mapping Strategy of Multi ... - NDMA

extent of flooding for an expected recurrence interval can be determined. In
traditional floodplain mapping, the requisite data and maps include the following:
The selected base (topographic) map with the surface water system
FEATURES DESCRIPTION
Hydrologic
data
Related maps
� Frequency analysis (including river discharge and
historical flood data), Flood inundation maps
� Flood frequency and damage reports, etc.
� Stage-area curves, Slope maps, Cross sections
� Hydraulic roughness
� Soils, Physiographic
� Geology, land use, Hydrology
� Vegetation, population density
� infrastructure and settlements
Table 6.6: Features Maps for floods
This dynamic approach requires extensive long term field surveys, with a
network of gauging stations that can develop the data needed for precise risk
assessments. Such extensive long term information is seldom available for river
systems in less developed countries. To obtain hydrologic data, one must contact
the appropriate hydro-meteorological agencies of government to secure available
data and maps. Soils maps and geological maps often delineate floodplains.
Topographic maps at suitable scales for the project should be available within
the country. What is more readily available is information derived from static
techniques which are capable of yielding information on flood hazard
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