Preface - Navigable Streams
The issue of "navigability" is one mired in confusion. To negotiate through that mire, it is helpful to recognize that concept evolved in three different areas - for three different purposes:
For the purpose of determining early jurisdiction where "admiralty" or "maritime" law had application;
For the purpose of determining "sovereign lands" of common law States at the time of admission to statehood, where private land and littoral rights were subordinated to the common public trust; or "private rivers" of the States where private land and littoral rights were "vested" under patent, not subject to public trust and required just compensation for "takings"; and
For the purpose of determining federal jurisdiction under the Commerce Clause upon which various various Acts of Congress have been based. (Such as the "Rivers and Harbors Appropriation Act," the "Federal Water Power Act," the "Clean Water Act" and the "Safe Drinking Water Act.")
In modern times, it is common to see a decision taken out of its context and asserted to support subordination of private land ownership to "public trust" without compensation; to assert Congressional jurisdiction over fisheries, riparian areas, water power, water allocation, water use; to assert Congressional jurisdiction over matters involving adjacent States; and to expand the boundaries of Commerce Clause beyond the limits established in Lopez,