i-Tree Support Forums

Preloaded streamflow data selected from a map is not downloading correctly correctly. If starting a project from scratch and downloading streamflow data from the map, you'll get an "Index was out of range" error. If other streamflow data had been provided in the project, the program will use that instead of what it attempted to download from the map. This is an issue we're actively working to resolve.

Working around the stream gage map bug:
Alternatively, users can also obtain their own streamflow data without using the preloaded map. For more information on that, please see the "Using your own stream flow file" of the following Hydro FAQ: Streamflow data / auto-calibration inputs

This issue has been resolved in i-Tree Suite v6.1.20. If you have the software already downloaded on your computer, open one of the apps and update through that. For example, open i-Tree Hydro then click on Help drop-down in the top menu bar and select "Check for Updates".