The section on National River Law discusses river ownership, use, and conservation law throughout the United States. Following is a review of what individual states can and cannot lawfully do with the rivers within their borders.
- The U.S. Supreme Court has ruled that rivers that are navigable, for title purposes, are owned by the states, "held in trust" for the public. This applies in all fifty states, under the "Equal Footing Doctrine."
- Rivers that do meet the federal test are automatically navigable, and therefore owned by the state. No court or government agency has to designate them as such.
- The federal test of navigability is not a technical test. There are no measurements of river width, depth, flow, or steepness involved. The test is simply whether the river is usable as a route by the public, even in small craft such as canoes, kayaks, and rafts. Such a river is legally navigable even if it contains big rapids, waterfalls, and other obstructions at which boaters get out, walk around, then re-enter the water.
- The states own these rivers up to the "ordinary high water mark." This is the mark that people can actually see on the ground, where the high water has left debris, sand, and gravel during its ordinary annual cycle. (Not during unusual flooding.) It is not a theoretical line requiring engineering calculations. Where the river banks are fairly flat, this mark can be quite a distance from the edge of the water during medium water flows. There is often plenty of room for standing, fishing, camping, and other visits.
- States cannot sell or give away these rivers and lands up to the ordinary high water mark. Under the "Public Trust Doctrine," they must hold them in perpetuity for public use.
- The three public uses that the courts have traditionally mentioned are navigation, fishing, and commerce. But the courts have ruled that any and all non-destructive activities on these land are legally protected, including picnics, camping, walking, and other activities. The public can fish, from the river or from the shore below the "ordinary high water mark." (Note that the fish and wildlife are owned by the state in any case.) The public can walk, roll a baby carriage, and other activities, according to court decisions.
- States do have authority and latitude in the way they manage rivers, but their management must protect the public uses mentioned above. They can (and must) prohibit or restrict activities that conflict with the Public Trust Doctrine. "Responsible recreation" must be allowed, but activities that could be harmful, such as building fires, leaving trash, and making noise, can legally be limited, or prohibited, in various areas. Motorized trips and commercial trips can legally be limited or prohibited by state governments.
- State and local restrictions on use of navigable rivers have to be legitimately related to enhancing public trust value, not reducing it. Rivers cannot be closed or partially closed to appease adjacent landowners, or to appease people who want to dedicate the river to fishing only, or to make life easier for local law enforcement agencies.
- State governments (through state courts and legislatures) cannot reduce public rights to navigate and visit navigable rivers within their borders, but they can expand those rights, and some states have done so. They can create a floatage easement, a public right to navigate even on rivers that might not qualify for state ownership for some reason, even if it is assumed that the bed and banks of the river are private land. Note that this floatage easement is a matter of state law that varies from state to state, but the question of whether a river is navigable, for title purposes, and therefore owned by the state, is a matter of federal law, and does not vary from state to state. Note that a state floatage easement is something that comes and goes with the water: When the water is there, people have a right to be there on it, and when it dries up, people have no right to be there. But rivers that are navigable for title purposes are public land up to the ordinary high water mark, so that even when the river runs dry, people still have the right to walk along the bed of the river.
- Only federal courts can modify the test of standards that make a river navigable for title purposes. States cannot create their own standards, either narrower or wider in scope. They can’t make definitive rulings about which rivers are navigable for title purposes, only a federal court can.
- The situation gets confusing when a state agency or commission holds hearings about navigability and public use of rivers. Landowners, sheriffs, and other people tend to think that such an agency or commission can create state standards that determine which rivers are public and which are private. But these are matters of federal law which state agencies cannot change.
- State agencies should make provisional determinations that various rivers meet the federal test of navigability for title purposes. These provisional determinations should be based simply on the rivers' usability by canoes, kayaks, and rafts. They should then proceed to the question of how to manage navigation and other public uses of the river. In these days of government cut-backs, the agency should look for solutions that use existing enforcement agencies rather than setting up new ones. Littering, illegal fires, offensive behavior, trespassing on private land, and numerous other offenses are all covered by existing laws, and offenders can be cited by the local police, sheriff's office or state police.