Stream Order

Question

Hello all. I am attempting to do change analysis on 3 stream networks I have. I do not have a DEM so I cannot use the hydrology tools in spatial analyst. Is there a way to determine stream order for my networks? A downloadable arc tool maybe?

I have the networks in both raster and polyline shapefile format. Thanks for your time.

MichaelBrown3 · Answer

Maybe there is a way to artificially create a flow direction raster?

MichaelBrown3 · Answer

I know....I could only wish I had a DEM though. The DEM method is so efficient. I have done what I am doing several times via that method. But ok, I did do the multi-part to single part and it does break up the polyline file nicely. Actually, its exactly how it would need to be prior to assigning stream order values. But still, is it possible to assign these values in an automated fashion?

Again, thank you for your replies.

DanPatterson_Retired · Answer

a network of any form, consists of a series of interconnecting paths between point of intersection.  In your case your network will discharge at  one point (ignoring the braided stream exit thingy) and as you head upstream it will branch of according to the surrounding terrain etc.  In your case as well, you network can only traverse in one direction.  If all those branches were combined together.  There are several ways of doing this, but you might have a look at the dissolve tool discussion at that URL and the general Dissolve tool  using the OID field to produce a single multi-segmented feature (can also be done in an edit session with ).  That can then be be broken into parts where river tributaries branch using the multipart to single part tool.  At least it is a starting point since what you really need is a flowdirection raster, hence a DEM to produce all the other bits