One of the more outstanding bits of information I found in my research on the islands was a very early statute about Breach Inlet. In 1733, an act called for “the making of a navigable cut near the passage called the Breach, now stopped up by the sea.” It stated that a deeper cut was needed to allow seaside planters to more easily get their goods to town by boat. It also was needed to keep open the “inland passage,” the complex of creeks that meandered behind the barrier islands from Charleston harbor to the Santee River.

For me, this was an eye-opening bit of lost history. I found the act accidentally; it was buried in the verbiage of another act for widening the road to the ferry (today’s Mathis Ferry Road). It nor future statutes offer any explanation of exactly where the cut was made, when or how. But it just might offer an explanation of how the inlet changed from being so shallow in 1700 that explorer John Lawson could not get his long canoe across at low tide, to being so deep in 1776 that the British could not ford the inlet and take Sullivan’s Island on foot.

Indeed, Breach Inlet is a bit of a mystery. First off, its very name raises questions. The definition of the word “ breach” means a break or a cut and it seems logical that this is how the inlet was so named. (By the way, it only became Breach Inlet in the 1800s. Prior to that, it was only referred to as “The Breach.”)

More to this point, a 1679 grant for Oldwanus Point, that point of land in the old village next to the Old Bridge), refers to the land as being “on the Great Marsh next the broken islands.” Ostensibly, these islands were what we now know as Sullivan’s Island and Isle of Palms and they were “broken” by what we now know as Breach Inlet.

(All this is juicy history, forgotten and lost in statute books; buried in proprietary period grants. What I call “hooey-boy” history.)

Were Isle of Palms and Sullivan’s Island once one very long barrier island? It is possible. There had been several horrific hurricanes in the decades before 1700 when Lawson gave us the first historical mention of “the breach.” Indians told the colonists of one storm so terrible the water had risen over the treetops. It is possible that one of these events created a cut between the two islands. This very thing happened most recently during Hurricane Sandy when the storm created three separate breaches at New York’s Fire Island.

One also needs to understand how Breach Inlet looked in centuries past. This is possible by looking at early maps which, even in the mid- to late-1700s, were remarkably accurate. The maps made in 1776 by the British show that the inlet was at least a mile wide. In fact, the Isle of Palms (then called Long Island) actually stopped at around where 4th or 5th streets are today. Thus, instead of the narrow deep inlet we know today, in 1776 there was a broad expanse between the two islands which was dotted with sandbars, much like the sandbars seen today that stretch across the ocean side of the inlet. In 1776, the inlet should have been fordable — except there was one narrow channel that ran close to Sullivan’s Island and it was at least seven feet deep at low tide. This is what foiled the British attempts to cross on foot.

That deep channel could have happened naturally. Or (ta da) it could have been the result of the “navigable cut” that was made in 1733 to allow the plantation boats through.

Creating such a man-made waterway was not unheard of at the time. The Wappoo Cut had already been dug on James Island, basically taking what had been a shallow, meandering tidal creek through marshes and making it deeper and straighter so plantation boats had a way to get from the Stono River to the harbor. Another similar “new cut” was made further south that joined the Wadmalaw River and the North Edisto. How they moved sand, plough mud and water remains a mystery to me. But they did. I am more and more astounded at the early colonists’ ability to harness and move water.

Also, as anyone who has ever built a sandcastle on the beach knows, once you dig that castle moat and allow water through, even a small trickle of water will eventually scour the edges and form a distinct, deep channel. Certainly, the cut dug through “the breach,” which was then “stopped up” by the sea’s creation of sandbars, would have naturally widened and deepened with time as hundreds of thousands of gallons of water rushed in from the ocean and poured back out from the marshes with every changing tide.

It also would have changed the configuration of the surrounding land masses. Any alteration of a coastal feature is one of cause and effect. A good for instance is the building of Fort Sumter. The fort was created on what was basically a sandbar in the middle of the harbor. The sandbar wasn’t terra firma — it moved and shifted according to the whims of the wind and waves. But once they shored it up with bricks and stones and made it a permanent island? The currents shifted, creating a whole new set of erosion problems on the south end of Sullivan’s Island. The Mount Pleasant waterfront (then a sandy beach) began to change to marsh. Hog Island (now Patriot’s Point) began to erode, as did Shute’s Folly (Castle Pinckney.)

Thus it is possible that the creation of a narrow channel through “the breach” in 1733 may have altered the configuration of the inlet forever. That one narrow cut may have created a cause and effect that, over time, created the inlet we know now.

Today the inlet is narrow and incredibly deep — 40 feet — and the currents that sweep through on a rushing tide move with astounding force. The water literally seems to come to a boil with unseen, roiling sub-currents that can suck one under in an instant.

All this (not to mention that it is a favorite feeding place for sharks) make Breach Inlet incredibly dangerous. People drown here yearly despite huge signs warning them to stay out of the water. Even the beach in some places is unstable. The sand, caught by the rushing tide, can suddenly drop into the inlet taking an unsuspecting beachwalker with it. Newspaper reports throughout the 1800s tell of many people lost “in the quicksands” at Breach Inlet in the 1800s. At some point I will take the time to count the number of people who have drowned there throughout history, or been caught by the incoming tide on one of the offshore sandbars and drowned trying to get back to land. They number in the dozens.

Breach Inlet is a place of deceptive beauty and fascinating history. It offers great fishing and is unparalleled for photograph-seekers. Porpoises love it and can almost always be seen leaping as they fish the tides. But tread carefully when you’re there. And please, stay out of the water.

Suzannah Smith Miles is a writer and Lowcountry and Civil War historian.