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Where can I obtain data on flood sites, land sewage systems, and property value?

I am a college student trying to obtain this data for a class project. If anyone can help that would be great. Basically, my hypothesis for this project is that land sewage systems that have not been ...
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0answers
53 views

How to make an inundation map?

My task is to calculate the area available for specific plant species in a natural reserve that has been reconnected to the tidal influence. First step is to create an inundation map for a natural ...
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0answers
8 views

FIRM Panel Metadata

Every month I need to check a check a list of FIRM panels (flood insurance maps published by FEMA) to see if they're still valid. I don't actually need to look at the maps, just either grab a ...
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0answers
23 views

What is the background processing of rainfall thresholding?

I want to create a flood map using Quantum GIS. First of all I create catchment area (flow accumulation). Then, I delineate a Channel Network by applying a threshold to flow accumulation. So I want to ...
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1answer
83 views

map flood inundation risk QGIS

I am using RADAR data to create a map of biomass estimates. I want to mask out all land susceptible to flooding because water-logged soils affect the backscatter ...and will have an impact on ...
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0answers
62 views

How to do a flood simulation without flooding the whole area and covering surface structures (with DEM)?

I have a high resolution DEM and want to do a flood simulation starting at a river. My hope is that the water runs into historical (now dry) river channels (in which I'm interested in) at first and ...
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1answer
59 views

What is the process for identifying a 20 year flood zone?

I am currently working on an assignment where I need to model flood risk areas. Firstly I was asked to identify potential flood risk zones based on the following criteria: identify areas that I ...
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0answers
166 views

Assessing Flood Hazard Risk Zones using DEM

My Question: What is the best effective way to quickly estimate flood hazard risk areas using DEM data? Ideally I am looking for guidance to move forward and perform this process over large areas ...
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1answer
82 views

Urban Hydrology Using With GIS

I'm researching how can I create a model urban floodplain depending on rainfall. And Which programme should I use? I want to show floodplain depending on temporal and spatial distribution on study ...
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1answer
73 views

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 ...
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1answer
46 views

Obtaining free satellite imagery for Australian floods?

How can I obtain free satellite imagery for Australia? I want to find the extend of flood in specific time. I have already tried land-sat.But unfortunately there is no data available for that specific ...
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0answers
30 views

flood mitigation

I would like to carry out flood mitigation using non-structural measures like wetland restoration, detention ponds and infiltration ditches or ponds. How can GIS help me in siting and visualizing the ...
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1answer
95 views

Digital Elevation Model Resolution

While I creat flood areas using DEM in ArcGIS, Which parameters do I consider to determine DEM's pixel size and resolution?
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0answers
82 views

Multicriteria Analysis for flood risk analysis

I have used a multi-criteria analysis which uses factor weighting for flood risk identification in a river basin using ArcGIS 10.1. My factors are rainfall, drainage, density, slope, and land use. ...
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1answer
181 views

Simplified flood “model” / estimation from elevation data

The goal is to present an estimation of potential flooded area. But still keeping it simple. I know this will not be accurate. The question is: will it be good enough for at gestimate / rough ...
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1answer
361 views

Creating weight raster for flow accumulation in ArcGIS for Desktop?

I am studying flood flow using ArcGIS for Desktop. When creating flow accumulation in hydrology, there is a weight raster. However, İf you do not have it, the programme sets its value to 1 which is ...
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1answer
192 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). ...
2
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1answer
187 views

Storm Water flooding

Is there a method in Arc Gis for mapping storm water runoff in an urban environment assuming that the sewers are at full capacity. I just want to map roughly where the water will flow over the land ...
2
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1answer
128 views

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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1answer
154 views

How to map flood areas from a set of points containing surface and height of water?

I am working on the damages made by the typhoon Haiyan. I use QGIS 2.0 with extensions and toolbox, and MapInfo. I have vectors, rasters of the place. I want to map the flood area along the ...
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1answer
331 views

Is there flood map prediction tutorial available to use with ArcGIS for Desktop? [closed]

I just want to ask if anyone knows a direct tutorial for flood mapping prediction. The scenario that my supervisor asked me is this: If we pour water on a specific location, where will it flow and how ...
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1answer
2k views

How to calculate the flood volume using a LiDAR DEM and a HEC-RAS floodplain polygon

I’ve got a vexing GIS analysis problem which is conceptually fairly straightforward, but in reality more challenging to figure out…. Basically, I need to calculate the VOLUME of floodwater within a ...
7
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2answers
1k views

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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1answer
450 views

Floor height creation from Aerial Lidar/Imagery only

I was wondering if it is possible to generate the floor heights of buildings from aerial lidar? We don't have terrestrial lidar or stereo imagery. I don't need the ground DEM level or the roof (DSM) ...
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2answers
1k views

Floodplain generation given river section polylines, flood level elevation points and a DEM of the land surface

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: 1) River cross section polylines ...
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2answers
197 views

Belgium Flood And Precipitation Mapping

Similar to this question, does any one know a source for free downloadable flood and precipitation maps for Belgium? Thanks all in advance. C