I used to think there were pretty much only two kinds of crazy as the word pertains to recreation:

There was crazy like the guy at a rugby house party I once met who garnished each and every libation he prepared himself by scooping a small fish from a burbling aquarium presumably kept up just for this purpose, dropping said critter into his cup. There followed the inevitable slurp and swallow.

Then there was major league crazy. Bungee jumping, sky diving, hang gliding crazy.

It took Jeff Wren to make me realize there are other levels of crazy in this world, levels somewhere in between my two previous yardsticks for yahoo.

Around 10 this morning, Wren, the laid-back, 44-year-old coach of the University of Maine swimming programs for the past two decades, is going to wade into the Penobscot River in Medway, turn right, and begin swimming some 65 miles toward Orono. He’s not going to swim the entire 65 miles all at once. He’ll do around 12 miles a day.

For his effort, Wren will raise in excess of $15,000 to be put toward the UM swimming and diving endowment fund.

This didn’t sound particulary crazy to me (no more than, say, swimming the English Channel) until I began to imagine what it would feel like to be in Wren’s place. And once I started imagining, I couldn’t stop.

I don’t know about you, but there’s something about the thought of swimming in a deep, dark river like the Penobscot that makes my breath start coming 10 times a second.

I’m cool as Mark Spitz in a pool. Love that blue bottom. Put me in a cold Maine lake or pond and I’m Johnny Weismuller. Even the Atlantic, with its Hollywood-fed reputation for producing things that would treat me like my rugby-house buddy’s aforementioned hors d’oeuvres, doesn’t scare me.

But a river?

Maybe it was the picture this paper ran last Wednesday morning. The one with the fisherman grappling an eel as big around as his arm and four feet long. The caption said it was a river eel. And the river it came from was the Penobscot.

Maybe it was the story my brother-in-law in Ohio told me. Seems he knew a scuba diver who once encountered a bunch of channel catfish while exploring a river bottom. The channel cats were bigger than he was. The encounter caused him to quit diving along river bottoms.

It’s not natural, things growing that big in fresh water. Then again, rivers are like that.

Even Wren, a swimmer’s swimmer, admits a certain unease when thinking about the environment he’s entering.

“I try not to think about what’s in there with me,” he said, only partly kidding on the eve of his departure.

My theory on why rivers inspire this feeling is, unlike other bodies of water, they have a sense of purpose. They have direction. They’re flowing some place. Whether we like it or not. So it doesn’t take much imagination to endow rivers with other human qualities. Like nastiness.

Do you do this? Every time I drive on a bridge over a river I imagine what would happen if part of the span gave way. I imagine my car dropping into the river and sinking in that cold… dark… water. I imagine me, in my car, drifting in the current along the bottom. I try to kick out the window in that pitch blackness as the water rises over my mouth, my nose, my eyes…. Then I step on the gas.

So I have spent the past couple of days imagining myself in Wren’s place, stroking, stroking, stroking for miles, rolling my head in the familiar rhythm of the Australian crawl. I look at tree-lined banks, blue sky, sunlight. Only with each roll of my head through the dark water I stare wide-eyed into the depths, looking, but not really wanting to see what I might catch staring back at me.

And I hyperventilate.

Irrational? Sure. Slightly phobic? OK.

It’s just so ingrained. Rivers aren’t made for swimming. For hundreds of years they’ve been our conduits for man-made waste. I’m old enough to remember what the Penobscot used to smell like from the old bridge on a July day. Bad.

Yeah, we started cleaning them up. Or, more correctly, we stopped dumping so much into them. But I have a feeling rivers remember. And they want payback.

I ask Wren if he will have his eyes open as he plows through the Penobscot.

“I have goggles. I’ll be looking,” he answered.

Jeff Wren is a brave man, I think. And a little crazy, too.