Each country may have ...
Published by Yoshimi Yoshida, Environmental Consultant at Yoshimi Yoshida Environmental Nutrition Consulting Service
Each country may have different policy/laws with respect to any water body.
The more serious problem arises when the water is shared by two regions/ two different regulations and countries -- ie US x Mexico Border Region / Transboundary issue. So for India, rivers shared by neighboring countries like Pakistan, Bangladesh have more complex issues -- as you probably know better.
https://legal-dictionary.thefreedictionary.com/Navigable+Waters
Navigable Waters
Waters that provide a channel for commerce and transportation of people and goods.
Under U.S. law, bodies of water are distinguished according to their use. The distinction is particularly important in the case of so-called navigable waters, which are used for business or transportation. Jurisdiction over navigable waters belongs to the federal government rather than states or municipalities.