Water Depth and repoducibility issue

[jeremyEudaric]

Deeply thanks for your previous help . Thanks to your help l saw that they had a poor match between my polygon and my DEM.

So l improved the matching as you recommended me :

However l still have my issue and the water depth ( in dark) is still not covering all or a big portion of the the flood map :

To bo honest with you at this point l do not really know what to do because l tried everything. l think the issue is the polygon an the way to do the flood map. Could you provided as well how you are doing your polygon and the code if possible ? On QGIS or python ? Thus, l could do exactly as you did and l hope that l could have a good results.

When l am running fwedt with your data or my data l have this issue all the time in the log file : ERROR 6: SetColorTable() only supported for Byte or UInt16 bands in TIFF format.
l tried the data that you used and l noticed the same issue but less important at some points the water depth can not recover the all polygon :

Think that is the issue because of this fwdet missed some part of the polygon but the issue is not the location. What do you think ? Could you run your data without issue ? May be l have a software or QGIS is if you can do it

Thanks a lot for your support.

Best Regards,

[jeremyEudaric]

Good morning so l tried this morning with a polygon provided by the Copernicus Agency mapping and l got the same issue :

l think maybe the its software issue ? The only error message that l have is ERROR 6: SetColorTable() only supported for Byte or UInt16 bands in TIFF format.

l had this error as well : :1: RuntimeWarning: invalid value encountered in greater

The warning may arise if you are performing operations on arrays with incompatible data types. So its probably because the tiff file needs to be Byte or Ulntt16 as the polygon but this l guess we need to solve it in the code ?

[cefect]

if you upload the new inputs I can take another look later this week; however, I'm guessing it is an issue with the low-res DEM. I suggest trying to track down a higher quality DEM (preferably LiDAR derived).

[jeremyEudaric]

Hi thank for your help unfortunately the LIDAR DEM are only available for US https://www.sciencebase.gov/catalog/item/543e6b86e4b0fd76af69cf4c that could be a limitation for reproducibility, l will try with a DEM of 10 m from TANDEM X and l will let you know .
https://drive.google.com/drive/folders/18km7boOaIIRpoDeJ7S1IlfVWItbRtolq?usp=drive_link

Thank you very much for your kindness

[cefect]

There are certainly LiDAR derived DEMs for Greece. I suggest searching open data repositories and journal articles

[jeremyEudaric]

Thanks lot for our help the issue was the DEM indeed MERIT DEM is no appropriate because its a 90 m DEM so l used Shuttle Radar Topography Mission (SRTM) 1 Arc-Second Global Digital Elevation Model und DEM-Derivative with a spatial resolution of 30 m

In the paper its says "The overall differences between the 10 and 30 m results (Figures 6a and 6b, respectively) are rela-tively small."

Thus how can we analyses those results ? l will probably to a ratio 300/10 to have the water depth at scale easy to analyze at the buildings level. What do you think ?

l am still looking for a DEM with a resolution 1m or 10 m for Greece.

When l will finish everything l will send you or post here all my steps for other users.

Best,

Jeremy