Take the 2-minute tour ×
Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. It's 100% free, no registration required.

Could someone please help me? I would need to create 100 buffers (500m x 1km) along a stream polylines. I know how to do it by using shortest distance but the buffers should follow the curves of the streams. Each buffer should start from certain point (sampling site) and go to upstream for a 500m. Some of my stydy-streams have multiple tributaries on upstream areas and in those cases the buffer should follow each branch.

So far I have a polyline-layer with 100 streams and point-layer with 100 sampling points snapped together with the end of study-streams. How to proceed from here? With some network tools?

I would really appreciate some help! Schematic figure describing my problem

share|improve this question
    
Is your network a PolylineM featureclass? You could linear referencing to achieve this; create linear events then buffer these. –  Hornbydd Jun 4 '13 at 14:40
    
Welcome to GIS Stack Exchange! Are you able to include a diagram to illustrate the result you are after? –  PolyGeo Jun 4 '13 at 20:17
    
I have no idea are my polylines in polyline-m fetureclass. I doupt it, if it should be done separately. My polylines are digitised and merged together for each stream. I tried to read about linear referencing from ESRIs help-pages but it was really difficult to understand how to get started. Should I create the event-tables first somehow? Could it be done by using the stream-attribute table? –  Blueridge Jun 6 '13 at 12:29
    
Now my features are PolylineM. I was able to create routes, but still need some help how to proceed from here? How do I get feature layer with 500 meter streams that I can buffer? –  Blueridge Jun 6 '13 at 13:04
add comment

1 Answer 1

This may help to some degree (as I think it is what you are after):

  1. You could use the Split Line at Point Tool to split the line where they intersect the points.
  2. Then using the Split line by distance function in the Editor tool bar, split the line by 500m. In saying this though, this will only work on 1 line at a time, so if you had 100 lines to buffer, it will be time consuming. Someone else might be able to provide a more efficient way for this step.
  3. In your stream polyline, add two fields - one for distance (for the buffer) and one for line buffer.
  4. Select all the lines you want to buffer and in the attribute table, add the text "yes" to the line buffer field.
  5. Use a definition query to only show the lines with "yes" in the line buffer field.
  6. Add 500 into the buffer field.

  7. Using the Buffer Tool, use the following parameters:

    • buffer field as the distance parameter
    • Full as the Side Type parameter
    • Flat type as the End Type parameter

If any one could improve on this method I would be interested to know a better way.

share|improve this answer
    
Split Line at Point Tool seems indeed to be too time consuming. But thanks anyway! This might help someone else. –  Blueridge Jun 6 '13 at 12:43
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.