As my home town of Baton Rouge joined other cities along the Mississippi in preparing for possible floods from the river’s steady rise, I sat in a downtown restaurant a few days ago that offered a view of the Mississippi from six floors up.

As dusk fell, a tugboat, reduced by distance to the dimensions of a toy, plied its way up the darkening current. To my left was our Old State Capitol, a castle-like building that struck Mark Twain as an architectural excess when he went down this same stretch of river in the 1880s. The Capitol, lit like a lantern against the twilight, seemed to still be winking at Twain’s reproach.

Even when Twain traveled these waters for his memoir, the river was already deep with history. This is the same river that opened much of the continent to European exploration, brought commerce to frontier towns and carried John James Audubon south to paint the birds of America. These people of the past saw, in large measure, what I also saw as I finished my coffee and gazed out the window: a thing of splendor — and danger, too.

As the headlines continue to announce the river’s rise, a phenomenon that has already brought pain to thousands and anxiety to countless others, what’s one to think of a natural landmark that alternates between such striking beauty and dread?

It’s a question that’s probably been asked as long as humans have lived near the Mississippi. Twain was familiar with the dilemma. His “Life on the Mississippi” often reads like the comic Twain of the lecture circuit, but there are times when his wisecracking narrative, like the river itself, takes unexpected turns into pathos. At one point, he confesses that his sense of the Mississippi is “tortured with the exquisite misery of uncertainty.”

People have been trying to engineer uncertainty out of the Mississippi for generations, building an ambitious system of levees to keep the river in check. But Mississippi poet and planter William Alexander Percy, in a 1941 reminiscence called “Lanterns on the Levee,” acknowledged that the river could be tamed only so much.

“Man draws near to it,” Percy wrote, “fights it, uses it, curses it, loves it, but it remains remote, unaffected. Between the fairy willows of the banks or the green slopes of the levees it moves unhurried and unpausing . . . in spring, high and loud against the tops of the quaking levees.

Percy wrote as a veteran of the Great Flood of 1927, a case study in the limits of human ingenuity. My generation got a similar reminder after Hurricane Katrina, when levee failures left most of New Orleans underwater.

There’s no reason to believe that a catastrophe like that will shake my city because of current conditions on the river. Officials have been working hard to prepare our levees before the Mississippi’s expected crest in a few days, and the mood here is one of measured vigilance yet widespread calm.

But in these days of waiting, I’ve also been thinking of Twain’s recognition of the fragile relationship between the Mississippi and those who live near it. Glancing at levees along the river, Twain noted that there “is nothing but that frail breastwork of earth between the people and destruction.”

Danny Heitman, a columnist for the Baton Rouge Advocate, is the author of “A Summer of Birds: John James Audubon at Oakley House.”