Hawth's Analysis Tools for ArcGIS

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 Summary

SNAP POINTS TO LINES TOOL
Input: a point layer, and at least one line or polygon reference layer
Output: a new point layer
Features:

• this tool will snap each point in the input layer to the closest point on the nearest line in the reference layer, provided it is within the user defined snap tolerance distance
• if any point is not within the snap tolerance distance of a line feature, it is not snapped to a line, and does not occur in the output file
• all attributes from the input table are copied to the output (snapped) table

Limitations:

• THE TWO LAYERS MUST HAVE A PROJECTION DEFINED AND MUST SHARE THE SAME PROJECTION, otherwise you will receive an Automation Error. I am working on making this limitation less stringent (on-the-fly reprojection)
• this program can take a fairly long time to run (several minutes)

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 Example

Figures A-C. In this simple example, four points occur near a line and one point is already on the line (Figure A). The Snap tool is run with a snap tolerance high enough to allow all the points to be snapped to the line (Figure B). Figure C shows both sets of points (green = before snapping, red = after).

 Help

Getting started. At least one point layer, and one line or polygon layer must be loaded into ArcMap in order to use this tool.

Setting a snap tolerance. It is recommended that you inspect how close your points tend to be to the lines before starting the tool. The larger you set the tolerance, the longer the program will take to run. This is especially true for layers containing relatively high densities of lines near the points.