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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Correspondence of 0m elevation height of a digital elevation model (Copernicus DEM) to mean sea level
I want to model future coastal flooding caused by sea-level rise under the latest IPCC scenarios at global scale. To this end, I use the Copernicus Digital Elevation Model (Copernicus DEM: https://...
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How to set up table for HAND based flood extents in ArcHydro?
I have a stream line and points with surface water elevation and a DEM of the watershed. I really liked the look of the HAND-based on Flood Depth and Extent but I would like to use the water elevation/...
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How to combine vector data (census) with raster data (inundation)
I am hoping to find a way to create a map showing the overlap of flood inundation and social vulnerability in QGIS.
I tried using zonal statistics, but it does not take into account the values, just ...
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Creating time series flood inundation map using NetCDF future sea level and DEM
I want to design a GIS tool that visualizes flood inundation maps for future sea level rise. the data that I need to use are NetCDF of projected Sea level rise for 10-year slices and DEM. The idea is ...
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Urban watershed delineation for flash flood events
I am currently trying to create urban watersheds using the ending points of flash flood events (in the NOAA Storm Events Database) as outlet points for a city. While doing so, the watershed that is ...
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Creating cumulative friction map
I am looking at bottom friction (Manning's n) values in relation to storm surge as large volumes of water flow over a surface.
In order to calculate total head loss occurring as water passes from the ...
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Detect sharp changes in elevation
I've been scouring the forums to see if there is a way to detect sharp, unnatural elevation changes greater than a certain amount in ArcGIS Pro. I've run across an issue in some DEMs where there are ...
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Issues implementing data fusion in EO Browser
I am trying to implement this custom script for flood mapping in EO Browser. I have added the datasets using the additional datasets button, and specified the required timelines, but I keep getting ...
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Get output from this code
I get this error
Error: Image. select: Pattern 'scale' did not match any bands. (Error code: 3)
from this code.
Map.centerObject(table);
Map.addLayer(table);
var before = ee.ImageCollection('...
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Extracting information from flood zone shapefile
I have a individual land price data, and I am trying to get the flood hazard zone category using the flood hazard zone shape file (link here https://files.hawaii.gov/dbedt/op/gis/data/...
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Displaying water movement paths over grid in QGIS
I have an external .csv file with "From" cell, "To" cell, X, Y coordinates for the "From" cell, X Y coordinates for "To" cell and flow rate for water going from ...
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QGIS - How to split and display Population Data according to District/Province?
I'm a complete beginner in QGIS, currently self-teaching myself through Youtube.
Current Problem: To split and display population data according to district/province
Project Background: To measure ...
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Creating a layer showing difference before/after flood (raster)
I ran a supervised classification on two satellite images - (i) before and (ii) after a flood. Now even before the floods, there were pre-existing water bodies which obviously don't count as flooded ...
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Generating extent of 1 ft rise in floodplain using ArcMap
I have a polygon layer that represents the max inundation extent along a stream for the one-year storm event (generated in hec ras).
If this floodplain was theoretically raised by one foot, what would ...
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Layer error: Image.rename: The number of names (1) must match the number of bands (10)
I am using Landsat 7 data (ee.ImageCollection("LANDSAT/LE07/C01/T1_TOA")) for flood mapping. I am trying to write the code but I'm stuck at a line where it says "Layer error: Image....
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Flood Analysis in QGIS
I am trying to use QGIS to assess what areas will flood if the river floods a specific height. I have a DEM of the area as well as a vector file of the lines of the river of interest. I cannot get a ...
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Should I re-scale all the dataset to one scale before running them into model?
I have been working on the Flood susceptibility modelling and also have identified, collected and generated data of around 26 controlling factors(indicators). Furthermore, i'm going to put them into ...
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Editing TIN surface by polygon using ArcMap
I'm doing a 2D hydraulic flood study of rivers in a 63 km2 basin. I have a raster of the topography (1x1 meters) that I have passed to TIN using ArcMap. Giving a z=0.3 meters, I get a TIN network with ...
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ArcHydro Point to Stream WSE DEM error
I have been trying to figure out how to make a flood delineation map, and the tool runs, but I'm getting this error "001003: Datum conflict between input and output." I thought this would be as simple ...
CommunityBot
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Generate topographical index from a digital surface model (DSM) to generate a flood susceptibility map [closed]
I'm performing a random forest model to generate a flood susceptibility map, I have LiDAR data from the study area where I generated Digital Surface Model (DSM) and Digital Terrain Model (DTM) raster ...
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How do I calculate high water extents?
Could someone suggest the right path to follow if I were looking to calculate the high water extents or potential flooding that could occur on a tidal river. I am working in ArcGIS Pro and have ...
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Delete geometries based on intersection with another layer
Working on QGIS, I have two layers
1. buildings (polygons)
2. flood area (polygons)
I want to get rid of the building located in flood plains. In other words, I need to find where those layers ...
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Calculating area in QGIS, defined as zone with relative elevation compared to a river
I’m trying to do the following in QGIS. When creating a 3D map, I want to follow a line or area of interest, such as a river, and create an area which is measured perpendicular to the line of interest,...
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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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How to check hydrological connectivity in flood fill techniques in QGIS?
I have a set of polygons (include their elevation levels), representing geographical areas. I want to check which polygons will be inundated if a flat flood level is given. Lets say 1m flood from sea ...
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Creating a Cross section of a river
I am using QGIS and HEC-RAS for my project. HEC-RAS needs a file for the river bathymetry. Since I do not have data for river bathymetry, I decided to use the Profile Tool in QGIS to create a river ...
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Offset raster boundary by elevation
I've been given a raster with flood elevation limits along a river, it's not a constant flood level so elevations range by ~35m. I need to do an analysis of the impacts if these elevations were 2m ...
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Raster manipulation in ArcGIS - Flood Mapping with HAND
I am trying to create flood maps using the height above nearest drainage (HAND) method using data from the continental flood inundation mapping (CFIM) project. I have the following data:
A raster map ...
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Measuring the intensity of raster pixels within buffers
I need to create a variable ranging between 0 and 1 to compute the intensity of a flood.
I have the raster file for the flood and the layer with the coordinates of the households that have been ...
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Showing overland flow route on DEM in QGIS?
I've been asked to produce a risk map at work which will show the possible flood route from sewers that surcharge (flood) during heavy rainfall. This is basically where I know the x-y coordinate (OS ...
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What does "slope.lt(5)" do in Google Earth Engine?
Can someone explain what ".lt" is in the code below, and how it works?
var hydrosheds = ee.Image('WWF/HydroSHEDS/03VFDEM');
var terrain = ee.Algorithms.Terrain(hydrosheds);
var slope = ...
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Using WofE (weight of evidence) in ArcMap
I need to use "weight of evidence" in a project about floodrisk
I heard that this model can be implemented in ArcMap but I did not find any videos in YouTube.
Can anyone help me?
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How to find out which areas are affected by flooding due to heavy rain?
I'm working on a little project to visualize affected streets of flooding due to heavy rain. I already got a DEM for my study area and filled the depressions with r.fill.dir.
Since I never worked on ...
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Assigning XS Cut Line Attributes like River/Reach Name, Stationing, Bank Lines, etc?
I'm working on a flood inundation project as my research study of my course. I am now assigning XS Cut Line Attribute (after constructing the XS Cut Lines) in HEC-Georas > RAS Geometry > XS Cut Lines ...
CommunityBot
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How to visualize inundation using Sentinel 1 SAR Data?
I am trying to visualize flooding after hurricane Harvey that made landfall on August 25-26 2017.
Based on this video, I've been able to obtain the basics of Sentinel-1 SAR imagery. Sentinel 1 comes ...
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Digital Elevation Model resolution [closed]
When I create flood areas using DEM in ArcGIS, which parameters do I consider to determine DEM's pixel size and resolution?
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How do I "flood" a terrain in Cesium to represent a high water level
I am thinking about using a plane object to represent a water level by rendering it as a certain height above ground using Cesium. Is there any example code that
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Spatial join - allocate values from joined polygon based on input polygon
I'm trying to determine population inside Special Flood Hazard Areas. To do this I'm doing a spatial join of census shapefiles with the FEMA National Flood Hazard Layer, using the Boolean field ...
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Creating local copy of an online Potential Flood Inundation Map
I am completely stuck, usually I can figure out how to create a local copy of hosted services, but this one I can't seem to get anything to work and any suggestions would be great.
Currently I can ...
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Google Earth Engine - Blend Sentinel-1 SAR Images?
Does anybody know why I am getting these strips across my Sentinel-1 images and how to fix it?
I am using multiple images over Mozambique between January 1st and January 13th.
I want to use this ...
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GRASS GIS: Time series of overland flow from r.sim.water
I am trying to perform an overland flow routing on a large area using r.sim.water in GRASS GIS. I've looked at other answers and made sure to set my computational region to the elevation raster I'm ...
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Explanation of HAND (height above nearest drainage) model procedure
i tried to follow this procedure Spatial Analysis - Calculate a cells elevation (height) above the nearest stream cell but i have some problem to understand everything. I mean the 2th answer in the ...
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Creating contours based on polyline using ArcMap?
I would like to create a simple floodplain map. I have LiDAR data with 1 meter accuracy. I have clipped it to a small area of interest that my computer can handle processing the LiDAR. I want to ...
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Multi-Spectral High Resolution Satellite images for flood events
I'm searching for multi-spectral high resolution satellite images for flood events.
I found a database of flood events from this link with dates and approxiamte locations (polygons) and I used the ...
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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
...
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Seeking vector file of extent of flood plain of 2010 Pakistan Floods?
I am looking to locate a shapefile or any vector file that can be used for analysis I am conducting of change in size of cropland in the Punjab region of Pakistan. The file of interest would reflect ...
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Flood records/database in Europe
Anyone knows where I can find a complete* database with the historic flood occurrence in Europe, at least since the 70's ?
I am looking for some information on the date, number of floods*, amount ...
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Determining flood extents based on a daily flow? [closed]
I have a DEM raster and daily average flows (e.g., 50Ml/day). And I want to determine how far the water extent goes when the flow accumulates for 7 days based on 50 ml per day?
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Issue with FEMA OGC Web Feature Service returning HTTP 400 error when attempting to download GML file
I'm trying to use an OGC web feature service in some software I am involved in developing. The service is described at the bottom of this page: https://hazards.fema.gov/femaportal/wps/portal/NFHLWMS
...
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Flood mapping in QGIS 2.4
I am trying to delineate flood-prone areas using QGIS.
I have a vector layer of the river and a DEM of the same area.
I have used the GRASS Module to get watershed by using r.watershed and I have ...
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