Checks you should always do after processing

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WarningBelow are a list of simple checks you should do before you start using the output of RivEX in your analysis.

1.Run your network through all the quality controls that RivEX provides before you attempt the network attributing tools.

2.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.

Mouth in network

3.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!

4.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.

Bad Stream Order

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.