“I know—but what’s your conjecture? Your line, you know—figuring—all that.”
The Shark considered briefly. “Well, I’ll tell you, Sam. Something’s happened.”
“Don’t need to tell me that!” growled Sam.
“You don’t understand. I mean, something’s happened more than a common spring freshet. The rain and the melting snow filled the river, as I saw, and as you must have seen, too. But ordinarily the river takes care of the most of the water—the Grants spoke as if there’d been little trouble in other years. This time, though—well, you know how much snow there was, and how quickly it goes under a rain like this. And Mr. Grant said they’d been having the storm up-stream a good while before it hit us. One of the dams must have gone out—that’d account for the tidal wave—if you can call it that—which came rushing down the valley.”
“I see,” said Sam. “It’s reasonable.”
“Of course it is—I’m telling you,” said the Shark simply. “Listen now, though! If nothing else had happened, once the crest of the wave had passed, we’d have seen the water begin to go down. Why? Because the natural drainage would be taking care of it. Pour a pitcher of water into a set-bowl, when the plug isn’t in the outlet, and after a few seconds you’ll see the level lowering. Drop the plug in place, and the bowl stays full. And I tell you, Sam, Sugar Valley is a lot like a big bowl.”
“But——”
The Shark disregarded the interruption. “Hold on! Let me finish. There’s a plausible explanation of our fix. Our big bowl is plugged, and if it is, the plug is an ice jam. Remember how narrow the gorge is at the foot of the valley? Remember how the bridge piers clutter it up? Well, then! Plain as the nose on your face! River carries down a lot of big chunks. They pile up against the bridges and wedge together. Then along comes a lot of logs and floating riffraff to fill in the cracks. That’s how you get your dam that’ll turn the valley into a big pond. The water can’t run off, so it stays here and keeps rising and rising.”
“But how much longer can it keep on rising?”
“Can’t say. Lack data. As I recall that map, though, I don’t believe we’ve seen high water mark yet—not by a long shot!”