Unfortunately, I couldn't find a direct link to a free PDF download of the AWWA C606 standard. The AWWA standards are copyrighted and typically require a purchase or subscription to access.
Downloading "free" copies of engineering standards poses significant risks: awwa c606 pdf free download
While I understand you're looking for a free download, I want to emphasize that AWWA standards are copyrighted and typically require a purchase or subscription to access. That being said, here are a few possible ways to access the AWWA C606 PDF: Unfortunately, I couldn't find a direct link to