# Find the point distance along a streams polyline?

Working in ArcGIS.

I am looking for a way to find the distance of a point along a streams polyline. I read Finding distance of point along polyline? and it seems to be similar to what I need...the distance of something downstream.

I went ahead and clipped my stream lines to only downstream to avoid any confusion on my part. I also created start points of each stream polyline.

I tried to use the 'Locate Features Along Route'; I get the distance the point is from the line...not how far down it is from a starting point...

I do not have the Network Analyst License.

Example of dissolved streamlines...gives not the closest route

Example of odd distances after minimizing available routes. Is point 1 really 81 feet down...if point 2 is only 50?

• A snap shot of your stream lines would help. Network Analyst probably is what you really want, but routes can do this, but only if you construct a single route for each stream course (from start to end, so some parts of the stream system may be duplicated to form separate routes for each tributary or branch). Locate Feature Along Route gave you the measure of the point on the route in addition to the side distance. If the route is simple and uses measures based on line length, then the end measure minus the measure of the start point would be your distance along the stream course. – Richard Fairhurst Sep 29 '15 at 20:21
• I posted an example of my streamlines. I understand now that the 'measurement' Locate Feature Along Route is giving me...measurement along the route...but from where? Its start point? – Petunia311 Sep 29 '15 at 20:51
• Is your data from the NHD? – Kirk Kuykendall Sep 29 '15 at 21:01
• Correct, data is from NHD – Petunia311 Sep 29 '15 at 21:08
• The measure is relative to the starting measure of the route, but the distance you want is just the end point measure minus the start point measure. Using measures to determine distance will only give good results if the route has no branches (i.e, it follows only those segments that make up the ideal path between the two points). As a result, a complex network like this is not good for LR if you want to be able to trace all possible downstream branches. A geometric network may be better for tracing the network, since it has a trace tool that respects upstream/downstream flows. – Richard Fairhurst Sep 29 '15 at 21:18