Questions tagged [flood]

A flood is an overflow of water that submerges land which is usually dry. Within GIS we often want to model a flood with terrain models.

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Increasing Flood Plain

I am doing a project where we are attempting to determine how many more buildings would flood if the FEMA flood plain increased by 1',2' and 5'. I have the elev of the flood plain rasters from lidar ...
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Generating floodplain generation given river section polylines, flood level elevation points and DEM of land surface? [closed]

I am looking to generate flood plain polygons to represent 20 and 100 year flood zones, in the most accurate and efficient way possible, given the following datasets: River cross section polylines ...
8
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Is it possible to conduct a flood model analysis with QGIS using a DEM?

Is it possible to conduct a flood model analysis with QGIS using a DEM? Need to simulate rising water levels on a 250k map.
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Converting polyline to polygon in ArcGIS Desktop for floodplain map?

I'm using ArcGIS Desktop 10.5 and working with a flood map from FEMA, which uses polylines with distinct attributes for each hazard zone (1%, 0.2%, floodway, etc). I'm trying to convert these ...
2
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1answer
735 views

Obtaining average value around polygon in raster for different cross sections?

I have elevation data in a raster, river (blue line) and the flooded area (black polygon) as shown in the image below: I want to find the water depth in the flooded area (inside the black polygon). ...
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Flood Elevation Setback

I have a floodplain layer with elevations assigned to it. Per scope of the project, I need to create a safety setback. The flood elevation is raised by 2 ft. and when the raised point extended ...