I am trying to calculate topographic symmetry. For this need to have a distance between mid line of a basin to streams and divided, like shown in Figure.
any one please let me know how to draw a mildline of basin in Arcmap.
For hydrology related challenges I would probably first look at ArcHydro (yellow.esri.com - /archydro/archydro/ ). Perhaps the basin length or longest flow path could be of any help:see http://downloads.esri.com/archydro/archydro/Tutorial/Doc/Arc%20Hydro%20Tools%202.0%20-%20Tutorial.pdf page 84 or see http://downloads.esri.com/archydro/archydro/Tutorial/Doc/Arc%20Hydro%20GP%20Tools%202.0%20-%20Tutorial.pdf page 100.
There is also a set of tools (Polygon to Centerline, http://www.arcgis.com/home/item.html?id=bc642731870740aabf48134f90aa6165 )that get's you a bit closer, but it will require some manual editing afterwards.
Edit: cross reference to The specified item was not found. and Arc Hydro
You may reach a larger and more pertinent audience if you were to post this in a more applicable space. The 9-1-1 GIS community while well versed, and very talented is rather limited in size and may not have the expertise you seek in this issue.
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