Urban Flood Risk Mitigation Model -- Errors 1 and 4


I’ve run the Urban Flood Risk Mitigation model and have had two errors pop up in the parameter log, errno4 and errno1:

2020-07-30 11:25:03,856 utils._log_gdal_errors(68) ERROR [errno 4] Unable to open external data file: /Users/Alexandra/Desktop/Data/landcover/2015_18/ecwp_landcover_nad83.ige
2020-07-30 11:25:03,865 utils._log_gdal_errors(68) ERROR [errno 1] /Users/Alexandra/Desktop/Data/landcover/2015_18/ecwp_landcover_nad83.img, band 1: IReadBlock failed at X offset 0, Y offset 0: Unable to open external data file: /Users/Alexandra/Desktop/Data/landcover/2015_18/ecwp_landcover_nad83.ige

I was wondering if I could get a bit of support on why these errors typically pop up and what I can do to start fixing them.

Thanks. :slight_smile:

Hi @farkasal, It appears the model cannot load your .ige raster files. Do these rasters also have an accompanying file with a .img extension? If so I would try using the .img file. Another reliable option is to convert your input rasters to Geotiff (.tif).

Hi @dave! Thanks for getting back to me. The raster has an accompanying .img, which is the original input file I used, so I was also confused why it was trying to read the .ige file. I’ll give the .tif format a try and hopefully that will clear things up.

Hi again @dave,

I tried out the .tif files and had no more error messages in the parameter log, but have run into the issue of my output values all being the same when I input the Q and retention files into ArcGIS. I’ve attached a screenshot for context below. Any ideas as to why they are coming out equal? I’ve also attached the parameter log.


InVEST-UrbanFloodRiskMitigation-log-2020-07-31–11_54_44.txt (36.0 KB)
Screen Shot 2020-07-31 at 12.41.02 PM

Hi @farkasal, I don’t know for sure what’s going on, but I would investigate a few things…Are there actual values in those output rasters? Besides the extreme min/max values in the legend? You could try adjusting the symbology to display a different range of values. If not, does everything look okay in your input data?

If nothing appears out of the ordinary, could you share all your input data so I can reproduce the problem? You may send me a link here or in a private message.

Hi @dave,

I’m happy to share the input data. Do you have an email I can send them to? I’m not sure they’ll be able to be uploaded to the website for size reasons.


@farkasal, a good solution is usually to upload the data to Google Drive, Dropbox, or similar, and then share a link with me. If you don’t wish to post that link here publicly, you may click on my name and send me a private message with the link.

Hi @dave,

I’ve resolved the issue! I had my supervisor run it on her own desktop and we got results. The main issue seemed to be that I use a Mac iOS and the .img files are recognized within the system as a disk image file, which I think may have been altering formatting. Regardless, thanks for your help and patience. :slight_smile:

Oh that is very interesting, thanks for reporting this. I’m glad you got the results you need!