WAGENER, SC — Trees hang so thickly over the Edisto River’s north fork that paddlers compare the setting to an enchanted, far-off land.

Even on the brightest days, parts of the north fork receive only mottled sunlight as the blackwater stream flows silently through the hardwood forests and deep swamps of Aiken, Lexington and Orangeburg counties in central South Carolina.

This remote nature corridor, where black bears and prehistoric fish are said to live, is so scenic and peaceful that it has developed a small, loyal following of hardcore kayakers and local outdoorsmen.

But the Edisto River’s north fork also is important for another reason: it’s one of two streams that form the headwaters of the ACE Basin, a 200,000-acre nature preserve known nationally for its wonders and South Carolina’s efforts to protect it.

So preserving the north fork, and its twin, the south fork, is vital to preserving the entire basin, biologists and river enthusiasts say. Pollution that goes in these smaller rivers eventually flows toward the Edisto’s broad main stem and the heart of the ACE Basin.

A recent proposal to increase sewer discharges to a north fork tributary has focused attention on the small river’s significance to the entire ACE region downstream.

“There’s no question the primary source of the ACE’s nourishment is the Edisto River, so what sense does it make to compromise that?’’ asked Columbia lawyer Tim Rogers, a former state legislator who grew up along the north fork and now heads Friends of the Edisto. “You should do everything you can to preserve your investment in the ACE Basin.’’

Located between Orangeburg and the coast south of Charleston, the ACE Basin is a mostly undisturbed region of forested swamps, old rice fields and historic buildings. Some of the best duck hunting in the state can be found in the ACE, noted for its tranquility and clean, undammed rivers.

The ACE is considered so special that many major landowners have signed agreements not to develop their property. Government agencies also have acquired property in the ACE, which includes a national wildlife refuge and a national estuarine research area. Those efforts have resulted in 200,000 acres of protected land.

On the north fork, the land also is relatively undisturbed. But unlike the Edisto River’s main channel, the north fork is not in the ACE Basin’s boundaries and there have been fewer initiatives to protect property.

The north fork, instead, has remained wild because of South Carolina’s historic growth patterns. Along the north fork, the banks are so sandy in places that the riverside wasn’t much use to farmers as South Carolina grew. And with Columbia and Charleston emerging as urban centers, folks left much of the north fork alone.

For those who have maneuvered the north fork’s narrow channel or walked along the banks, the experience is as memorable, in its own way, as a trip down the Edisto’s main stem through the ACE Basin.

“It’s like canoeing through a tunnel,’’ veteran Columbia river guide Guy Jones said of the tree-shrouded, 75-mile north fork corridor that stretches from near Monetta to Branchville, south of Orangeburg. “You never know what you’re going to see around the next bend. It’s always kind of an exploration.’’

Jones said the wild character of the north fork wasn’t lost on a European college student he took down the waterway several years ago. As the small group he was guiding kayaked above the ACE Basin near Orangeburg, Jones said the student looked wide-eyed at the canopy of trees hanging over it.

“She said, ‘This is like a Russian fairytale,’” Jones said. “It had an enchanted quality to it.’’

In addition to the scenery, the dense tree canopy on the north fork provides plenty of habitat for brightly colored songbirds. The shallows along the river attract wading birds, including great blue herons that feast on small fish.

Deer, mink, coyotes, wild turkeys, raccoons and bobcats thrive in the woods – and they’re sometimes easier to spot than novice paddlers might think because the river is so narrow.

Wagener resident Steve Wells said none of that compares to the eyeful he received about a year ago. While crossing a bridge over the Edisto’s north fork, Wells spotted a large bear ambling along the country road near the swampy banks.

“I was just amazed,” said Wells, who said he saw a cub another time. “Like a dummy, I was going to stop the truck and walk over and see what I could see. But then I said, ‘Fool, that’s a bear.’

“He was real close to the river, less than a half a city block away.’’

Bears aren’t commonly found in Aiken and Lexington counties. But in this case, the bruin might have wandered down the wild river corridor from the mountains or up from the ACE Basin.

State fish studies also have identified prime habitat on the north fork for seven rare species, including the American eel, according to the S.C. Department of Natural Resources.

Bill Marshall, a state Department of Natural Resources river specialist, said he received a report about one rare fish while visiting the upper extremes of the north fork several years ago. He figures it was a shortnose sturgeon, a federally protected endangered species that dates to prehistoric times.

“We were at a property there ... and somebody was hooting and hollering about some strange fish,’’ he said. “It doesn’t surprise me.’’

Marshall said increases in sewer discharges can’t help the north fork of the Edisto or the ACE Basin.

“We all know there is this incremental cumulative impacts question that lingers,’’ Marshall said.