Where can I find the link to Arc Hydro that is compatible with ArcGIS 10.2?
Please reference this forum post here
Arc Hydro Installation - 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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