Where the River Ends and the Law Begins: Trespassing In Different States...

Kevin Wolfe
Jun 8, 2025
4 min read

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Kevin Wolfe | Sunday Cast | Casts That Care

What Counts as Trespassing on a River?

Let me start by saying this: if you have a pond—or even a lake—that starts and ends within your property, I get it. That’s yours. It doesn’t flow. It doesn’t cross boundaries. It’s a contained thing. But a river? A river doesn’t respect fence lines. It starts in one place, flows through another, and ends somewhere else entirely.

And yet somehow, we’ve let each state decide its own rules on who owns what when it comes to water.

What we end up with is a system so fragmented it makes a topographic map look straightforward. If you fish across multiple states, you’re likely operating under entirely different definitions of “trespassing.”

Same River, Different Rights

Take the Colorado River, for example. It flows through both Colorado and Utah, but the rules change dramatically across the border.

In Colorado, floating through private land is legal as long as you don’t touch the riverbed or riverbanks. The water is public, but the land underneath often isn't. This legal gray area has led to numerous court cases, and the Colorado Supreme Court has made it clear: step out of your boat, and you're in tricky territory.

Now go downstream to Utah, where things were once more generous. Before 2010, Utah followed a Montana-style model that gave anglers the right to wade and walk below the high-water mark. Then came the Public Waters Access Act, pushed by private landowners. Now, in Utah, the landowner can own the streambed and bar you from walking or anchoring, even if you're in the water.

In Montana, anglers still enjoy access below the high-water mark on streams and rivers, whether the stream runs through private property or not. And in New Mexico, streambeds can be entirely private, access depends on landowner permission.

Back east, it’s no better. In Pennsylvania, landowners who own both banks of a non-navigable stream can claim the water itself as private. But larger, navigable rivers, like the Susquehanna, are public. New York takes a different tack: if a waterway has ever been used for commerce, it’s generally open to the public, even if it runs through private land.

All of this creates an impossible reality: the same river could technically be public in one state and private in the next. And no one knows what’s legal unless they’ve already read the lawsuit.

Not Picking Sides—Picking Clarity

This isn’t a pro-public rant or a private-property sermon. If you forced me to pick, I’d say: if you’re in the water, you’re not trespassing. I’d even go a step further and offer anglers a 3–5 foot grace zone along the bank in case they need to get out and walk it back.

But that’s not really the point.

The real problem is that nobody knows the rules, and the rules change from one side of the mountain—or river—to the other. You shouldn’t need a legal degree and a GPS just to know whether you’re breaking the law by fishing a river you’ve fished for years.

Themes Across the Country

There is a general trend if you zoom out. Out West, where public lands dominate, access tends to be more generous—though states like New Mexico and Utah have pushed back on that. In the East, especially the Mid-Atlantic and South, private land rights are often more rigidly protected, and many waterways are posted with little clarity.

Meanwhile, Midwestern states like Michigan and Wisconsin often favor public trust doctrine, meaning rivers held in trust for the people are generally open to fishing, wading, and boating—up to the ordinary high-water mark.

But there’s no consistency. Same river. Different rules. Different enforcement. Different culture.

Rivers Move. The Law Should Too.

Trying to chop a living, moving body of water into 50 different legal interpretations is not just confusing—it’s hostile to everyone who cares about rivers.

Landowners should feel protected. Anglers should feel confident. Right now, no one does.

Make It Make Sense

This isn’t just about fairness—it’s about keeping people from fighting over misunderstandings. There are anglers who’ve been screamed at for simply standing in the water. There are landowners who have no idea what their actual rights are. There are police officers and wardens who don’t even enforce the law the same way.

If we had a universal trespass law for rivers, this all gets easier. Whether it favors access or property, at least we’d all know where we stand.

Until then, we’ll keep checking state regs like we’re filing taxes—and hope that wherever we wade, we’re not unknowingly crossing a line that changes every 30 miles.

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