As far as I know they aren't released yet. The river and geo tools were just released so I would assume they will be coming out soon.
Or rather, I hope they will be coming out soon.
Great to see a good question about availability of the Productivity Tools for Civil 3D and just as @BrianHailey has said they are not quite available yet.
That being said you can check the availabilty of the tools by going to https://manage.autodesk.com ->Civil 3D -> "Updates & Add-Ons" I am inserting a photo to demonstrate what is currently available.
I do not have an ETA for the Productivity Tools but thought I would share how to find out when they do come out.
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The productivity tools aren't available via manage.autodesk.com, at least not for previous years. For the 2018 version, they can be found in the Knowledge Network HERE.
Thanks again @BrianHailey for posting the download link.