Where can I find the link to Arc Hydro that is compatible with ArcGIS 10.2?
Please reference this forum post here
Arc Hydro Setup Versions and Documentation
This might be what you are looking for.
Careful about 32-bit versus 64-bit: I tried loading the latest release for 10.2 and it didn't work. I mean, it installed without issues, but the tools did not work. Then I realized the latest release was for 32-bit, but I have a 64-bit machine. So I downloaded an earlier release for 64-bit, and it worked.
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