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I have a series of buffers around points that I want to intersect with FEMA's National Flood Hazard Layer. My goal is to find out which of the buffered points fall within 1% and 0.2% flood chance zones.

Unfortunately, when I open the Intersection tool, I cannot select the Flood Hazard Zones layer as an input -- it just isn't showing up. This layer comes from an ArcGIS REST connection to FEMA's NFHL server that provides the Flood Hazard Zones. Here are the Properties of the layer:

Layer Properties

And here is the screenshot showing the Intersection dialog and the dropdown that doesn't show the Flood Hazard Zones layer:

Intersection tool dropdown menu only showing the buffers, not the Flood Hazard Zones.

Why can't I select Flood Hazard Zones as a layer to intersect on? I have a suspicion that there's something about this layer that makes it different from the other layers I'm working with, but what?

I've already tried: checking that the projections are all the same, converting the layer from raster to vector (got a nondescript error), and closing/reopening everything.

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The intersection tool works only with vector layers. It does not work with raster layers or WMS layers. As mentioned in the intersection tool help, the input paramters should be of type vector only. Therefore, you need to supply Flood Hazard Zones in vector format if you want to use the intersection tool.

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  • Ah, I see. Is there a way to convert what I have into vector or do I need to find a new data source altogether? Or, is there a way to reach my goal using this data with a different tool? – DK Kennedy Jan 27 at 17:22
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    You need to find a new data source in vector format to use the same tool. This Flood Hazard Zones data displayed in your question is useful when you want to validate your results or use it as background to prove something. You cannot use it directly in any geoprocessing tool because it is rendered as a picture. – ahmadhanb Jan 27 at 22:11

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