They’re everywhere.

It’s another story percolating through Bowling Green for years: Everywhere in town, there are caves. Caves under Greenwood Mall. Caves under houses. Caves under Western Kentucky University.

But this rumor is different from most urban legends. This one’s true.

The most dramatic tale I’ve heard ends with, &#8220… and one of these days, maybe when the New Madrid Fault goes again, this whooooooole town will just go ‘Whoosh!’ and disappear underground!”

That, fortunately, is not the case. Yes, there are caves all over the place.

But most of them aren’t even remote threats to the roads and buildings above. It’s a matter of depth and size.

&#8220The true definition of a ‘cave’ is something that a person can go into,” City Hydrologist Tim Slattery said.

There are 22 such throughout Warren County that have been mapped by students and staff at Western’s Center for Cave and Karst Studies, he said.

At least two publications, one from the late 1960s and another from the mid-1980s, have charted caves in Warren County, said Chris Groves, professor of geography and geology at Western.

&#8220There’s been new things discovered since then,” he said.

I spent some off-time during college years personally investigating a few cave stories. It is true that, before the current dam was built, a walk from the entrance of Lost River could send you several wet miles underground. I’ve wedged into most crevices of the now-off-limits Lampkin Cave, and found they don’t go much of anywhere.

But stories of accessible caves under campus itself didn’t pan out.

I heard of a cave entrance under the concrete Colonnade on top of the Hill. Not true – I’ve been under there. Some friends and I heard of caverns under Egypt parking lot, but a damp and stinky expedition turned up nothing more than storm drains and narrow pipes heading farther down.

Those narrow pipes, however, do provide the grain of truth that underlies – literally – the stories.

&#8220For the most part, the cave systems are our storm sewer here in Bowling Green,” Slattery said.

Throughout the city, pipes are driven down in troublesome drainage spots until they reach a void big enough to hold water – and can do so almost anywhere, he said. The resulting drain is called a dry well.

&#8220It’s a pretty safe bet that Bowling Green has more dry wells than any other city in the country,” Slattery said. &#8220But Bowling Green is one of the largest cities in the country built on a karst sinkhole plain. We live on a unique landscape, no question about it.”

The city isn’t sure how many dry wells are out there, since they’ve been created unofficially for more than a century. But Public Works is cataloging all they can find – more than 700 so far – and Slattery estimates that there are probably 1,000 or more.

The wells can vary considerably in depth, he said.

&#8220We have some 10 feet deep, some over 100,” Slattery said.

But they generally range between 60 and 80 feet in depth, he said.

Now federal law and common sense demand that area residents keep what flows into our storm drains relatively pure, but our civic forefathers were not always so perceptive, as the May 1921 issue of &#8220Popular Mechanics” demonstrates.

Bowling Green then proudly touted itself as a city of 15,000 with &#8220not a foot of man-made sewer pipe.” Current residents’ grandparents relied instead on an, uh, organic method.

Whenever a new house was built, someone – often a local who fancied himself able to &#8220dowse” for unseen voids with a peach twig – would be asked to find the nearest limestone crevice that would take water from a garden hose, according to the magazine article.

If the water went out of sight and out of mind, &#8220That’s where you put your poopie-line from your house,” Slattery said.

&#8220It is then approved by the city inspector, and the house has perfect sewer connection,” says the article, a favorite with modern geology students and water managers. &#8220No city has a more sanitary system.”

Ewwwwww.

The story acknowledges that the waste eventually seeped into the Barren River, which was always used for drinking, but alleged that it was somehow &#8220purified” by passing through limestone.

Fortunately, several decades of actual sewers and water-treatment standards have allowed the caves to rinse themselves clean.

None of the other caves in Warren County can compare to Lost River Cave, Groves said. It winds for three or four continuous human-sized miles under Nashville Road and beyond.

About 7 miles of Lost River Cave have been mapped, and at least five entrances marked, but the river runs through flooded or partially-flooded passages for at least another 4 miles, all the way to Lost River Rise in Lampkin Park, Groves said.

Lost River itself briefly surfaces off Elrod Road, at a site called the &#8220church window,” before flowing into the park valley, Slattery said. After heading back into the cave, it rises in a spring next to Lampkin Park and flows into Jennings Creek, which then flows on into the Barren River.

A team from the Center for Cave and Karst Studies worked on the flooding problem in Egypt Lot, and figured that the passages they hit through the dry wells there connect to Lost River too, Groves said.

Divers entered Lost River Rise near Lampkin Park and found that it goes down about 40 feet, then levels out into a passage perhaps 10 feet high and 100 feet wide, he said.

There are rumors of more caves associated with Lost River, from a reported section that no one can now find to a flooded passage running from near Basil Griffin Park into the Lost River Valley, Groves said.

State Trooper Cave – part of which collapsed in 2002 beneath Dishman Lane – also carries a tributary stream into Lost River, but is not linked by any walkable passages, he said.

In the mid-1980s Groves helped map more than a mile of Lost River that runs beneath the old Bowling Green Mall and across Nashville Road toward the current Kroger shopping center, he said.

That stretch, a tight squeeze that can take 10 hours to travel, still has a few small unexplored side passages, Groves said.

A group from Western just finished mapping Bypass Cave, the litter-strewn cavern that begins by the China One Buffet King parking lot, Groves said. It winds under the road toward Baskin-Robbins Ice Cream and ends in a collapse beneath Zaxby’s, he said.

None of the local passages connect to the Mammoth Cave system, as a few people think, Slattery said. Warren County caves are separated from Mammoth by the Barren River, he said.

Mammoth Cave and the surrounding karst region attract many expert cavers to Western, so the local system is pretty well-explored, but new cavities do occasionally turn up, Groves said.

&#8220It’s pretty cool for me to know that in Mammoth Cave, or even here in Bowling Green there’s the chance of finding something new, of exploring something no one’s ever seen,” he said.

Though our local underground network is pretty safe for humans, humans aren’t necessarily healthy for the caves; and, in the long run, can be harmful to ourselves.

&#8220Everything, pretty much, that hits the ground here – that we dump or rainwater that falls – eventually gets into the cave system,” Slattery said.

That’s why the city has started a &#8220Keep It Clean, Bowling Green” campaign, warning people not to dump oil or anything similar down street drains, and to watch potentially toxic runoff from their own yards: What goes down your curbside drain, or seeps through your lawn, reappears in springs that feed the Barren River – which is where all local residents get their drinking water.

And there’s usually not a lot of filtration time, since underground streams can move as fast as water on the surface, Slattery said.

In the 1980s, that created a major problem. Several large underground gasoline tanks had sprung leaks, and their seepage, which floated on top of cave water, wafted up through cracks in the rock, filling area home and school basements with toxic fumes, he said.

The result was an emergency declaration by the Environmental Protection Agency until the fumes were traced to their sources. With the tanks plugged, the fumes gradually dissipated, but any modern-day leak or deliberate dump could duplicate the danger, Slattery said.

– Jim Gaines can be reached at jgaines@bgdailynews.com.