Converting a NEXRAD Rainfall Map into a Flood Inundation Map by ...

case that was developed for Map2Map is the use case of Design Storm Events asthe source of precipitation. The “historical event” use case is mostly gearedtowards automated floodplain mapping of all the range of possible realizations ofprecipitation. This capability can be exploited in the generation of “designfloodplains” (avoiding classical assumptions of rainfall and runoff with sameprobability distributions) and to readily generate rating curves (under newdevelopment scenarios) at any desired ungauged locations and for flood impactanalysis studies. The historical event use case can also be easily extended toprovide necessary groundwork for near real time flood forecasting.4.2 MODEL COMPONENTS FOR THE DESIGN STORM USE CASEThe “design storm” use case is mostly geared towards planning andmanagement for the purpose of structural designs, regulatory floodplain mapupdates, and prioritization of projects. For the current Map2Map application, analternative for the design storm use case was developed such that it reuses most ofthe process components in the historical event use case. Two new processes hadto be developed for the design storm use case which replaced the first threeprocesses of the historic event use case. Figure 4.52 depicts the entire Map2Mapworkflow for the Design Storm use case starting at the upper left yellow box(DStormSeries process) end and ending at the lower right end (Create FloodPolygon from Surfaces process model).As mentioned above, the complete workflow for the design storm use casestarts with the Sub-Model “DesignStormSeries” and follows with the user-defined177