Download the BETA 10.1 Arc Hydro Tools (32MB) here:
Please contact email@example.com with any and all feedback.
Arc Hydro Tools are free with your ArcGIS software license.
In the coming months, documentation for the tools will be available on the Hydro Resource Center. For past versions of Arc Hydro Tools, please see the Hydro Data Model page, and check back to the Hydro Resource Center, and Hydro Blog for more updates!