Had a pump cavitation scare on the Columbia River last Tuesday

We were pulling gravel near Hood River when the suction pressure dropped fast and the pump started making that awful rattling sound. Turned out a big piece of river debris had gotten past the screen and was blocking the intake. Shut it down, cleared the line, and got it going again in about twenty minutes. Anyone have a good trick for spotting that kind of blockage before it gets to the pump?

3 comments

3 Comments

the_sean3mo ago

Man, that's the worst sound in the world. Have you thought about a cheap underwater camera on a pole? I know a guy who rigged one to a gopro housing and just pokes it down near the intake when things feel off. It's not fancy, but seeing is better than guessing. Lets you spot a log or a tangle of weeds before it becomes a real problem. The murky water up there makes it tough, but even a blurry shape can tell you what you're dealing with.

ericgonzalez3mo ago

Sounds pretty dramatic, but it's just a normal part of river work. That noise is bad, but a quick shutdown usually fixes it. Not exactly a life-or-death emergency.

emerycarr1mo ago

Yeah, that rattling noise is something you don't forget. @ericgonzalez says it's no big deal, but I had a buddy lose a whole pump out on the Willamette a few years ago because he didn't take it seriously. That underwater camera idea from the other comment is smart though, I've seen guys use a cheap snake camera from Harbor Freight and it works good enough.