Help with creating a river mileage shapefile needed

[MichalDudek]

Hi, I need help and/or advice with creating a river mileage shapefile using the data I have:

- river network (linear shapefile - vector data)

- ordinate data (altitude data in point shapefile) spread across the river network (so I know which way the river flows).

There are two problems with the data I have:

1. the river network consists of smaller sections creating rivers - it means that one river is divided into smaller sections but in the attribute table of each section there is an attribute with the name of the river so it can be easily identified how many sections each river has

2. the river network is 300 000 sq. km so it makes the analysis very laborious.

I decided on the process to do and I need your advice if it is ok and how to do it step-by-step in ArcGIS 10.2.

First, I am planning to join each section of the river into one line so every river with different name attribute would be separated. Q: how to do it using the fact that the sections have the same name attribute? Any python script?

Secondly, I need to determine spring and mouth for every river based on the ordinate data (point shapefile) - with tool would be the best for it, how to make it?

Lastly, I need to create the point shapefile with the mileage points across the river network at 100 interval. The shapefile will be huge. How to do it? Is it possible to make steps 2&3 as one step?

I would be grateful for any advice on that.

Kind regards,

Michal

[FC_Basson]

For your first step you can use the Dissolve tool to "unsplit" the features by similar attributes.

Not sure about the second step, but I reckon if it is a proper network dataset it should be easy to determine the start and end node for each river section.  Also take stream order into consideration here.

For your last step you can have a look at the COGO tools.  Just make sure you are working in a meter-based projection.

[MichalDudek]

Thank you for the answer, the first step went well.

For the second and third steps the problem is that the river network is large, quite complicated (many channels connecting rivers are included in the same shapefile) and pretty dense. The best way would be to find a tool/script that is able to determine the start of the undivided river and insert a point at given interval for the whole network.

[DanPatterson_Retired]

So basically, you want a network tree constructor that starts at the stream mouth, traverses upstream, densifying as it goes, determining the branches that it encounters and so on and so on.

Are you intending to want Strahler or Shreve or other stream ordering as a side benefit?

I haven't seen one, but I recollect a similar request within the last 10 years.

[MichalDudek]

Correct. Given that there are more than a hundred of stream mouths and each mouth (connected with another sream) must have a 0,000 mileage point and the mileage of the river that it flows into cannot take into account the 0,000 point of another river.

I don't intend to have any side benefits.