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I am trying to run an IDW analysis based off stream and springs data.

I have the hydrography.eoo file from GeoComm but am now wanting to create a point layer of the springs in the area which show up on the DRG.

Is there any way to extract point data from a Digital Raster Graphic (DRG) in ArcMap without manually creating a spring layer?

I'm using ArcGIS 10.1 for Desktop.

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    What's a DRG? have you imported the .e00 file? if so, does it identify the springs?
    – Michael Stimson
    Commented Aug 11, 2014 at 23:07
  • @MichaelMiles-Stimson DRGs are basically scans of USGS topo quad maps.
    – Chris W
    Commented Aug 11, 2014 at 23:48
  • Thanks Chris, I did not know that. It seems that it's clarified in the edit. Is the format similar to ADRG/CADRG? from memory they contained layers within layers and it might be possible to drill down to springs.
    – Michael Stimson
    Commented Aug 11, 2014 at 23:52
  • @MichaelMiles-Stimson I'm not familiar with those formats and haven't used them. From a quick search it looks like they may be similar to the map products mentioned in my answer - ie text coordinate tables associated with the raster for searching/locating points. To my knowledge, DRGs are just straight georeferenced scans with no such additional info or indices. All the ones I've used are basically just a tif - that's how the mapping companies can still make money from them even though the USGS provides the digital map for free these days; providing additional data/search/display capabilities.
    – Chris W
    Commented Aug 12, 2014 at 0:23
  • Sounds like the digital data is the way to go. I'd like to know what's in the .e00 interchange file though, it sounds like it might contain at least some of the springs - or maybe not. I'd be doing a bit of searching for downloadable data before heads-up digitizing, depending of course on the amount of area to cover, if it's only going to take a few hours then I'd digitize it.
    – Michael Stimson
    Commented Aug 12, 2014 at 0:27

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The short answer is no - the question is basically about automated feature extraction from imagery.

Some of the data that goes into the quad sheets is available as vector data. The National Hydrography Dataset is where you'd start looking. You can grab the point layer, which has stream guages, dams, and 'other' (including seeps/springs) from the National Map (look for the Click Here... link to launch the viewer). Springs/seeps that appear on the DRG may or may not be in the NHD data and vice versa - it depends on how old/when the data on both sides was verified.

The GNIS (named points layers) may have some in there as well. Local/state sources might also have the data you're looking for in a consumable GIS format.

Otherwise you're looking at commercial aquisition. For example Garmin's Topo data has points for at least some springs if you have it and can extract it - I believe some of their data is derived from quad sheets, but don't quote me on that. Often in those types of mapping software (National Geographic Topo!, whatever Delorme's is called, etc) they had somebody go in and digitize those named points on the map to create searchable data for the software.

Depending on how big an area you're looking at, digitizing your own layer might be fastest. And of course you'll want to keep in mind how old the map that DRG is a scan of is - springs may have dried up since it was last updated.

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