Checks you should always do after processing
Below are a list of simple checks you should do before you start using the output of RivEX in your analysis.
- Run your network through all the quality controls that RivEX provides before you attempt the network attributing tools.
- Construct the river mouths and sources of your network and display them on top of your network. A mouth should not occur within the network as indicated by the green circle in the image below. Equally sources should not occur within the network.

- With Strahler stream order, no polyline should have a zero order, so do a simple query on the Strahler field searching for all values with a zero value. Equally see what the highest stream order value is. If your sequence goes 1st, 2nd, 3rd, 4th, 5th, 8th then something strange has definitely happened!
- Colour code your river network and just look at it! It should follow a logical colour change as you go from source to mouth. Look at the image below.

Arrow 1 indicates an error, two upstream 3rd order rivers have joined. Under the Strahler system the polyline pointed to should become 4th order (red), but it still remains green.
Arrow 2 shows a 4th order (red) flowing into a 2nd order river (cyan) and arrow 3 shows a 2nd order river (cyan) flowing into a 3rd order river (green).
If this was a large river network and you were just looking at the values in the attribute table then you would have probably missed this error.
