I finally learned why you never skip the pre-dredge sweep on a sandy bottom

Tbh I was working a job down in Mobile Bay last month on a little cutter suction dredge. We had been running smooth for two days straight, nothing but fine sand coming through. I got lazy and skipped the pre-dredge bottom sweep one morning because I figured it was all the same. Turned out there was a buried section of old cable maybe 6 feet down that I didn't see. Wrapped up around the cutterhead so bad it took me four hours with a torch and a grinder to cut it free. My boss was not happy, said it cost us almost a full shift of production. Has anyone else dealt with a surprise buried cable or pipe on a job? I'm thinking about getting a magnetometer for next time but they are pricey.

2 comments

2 Comments

cameronn6216d ago

Man I did the exact same thing and my cutterhead ended up looking like a metal spaghetti dinner.

jackson.matthew16d ago

Man you are not alone on that one. I had a similar thing happen up in the Great Lakes a few years back, we snagged a old telephone cable that must have been buried for decades. Wasn't even on any of the charts or survey maps we had. I spent a whole shift with a cutting torch and a lot of bad words. A magnetometer is a solid investment if you can swing it, but even a cheap fish finder with a good bottom scan can help you spot weird shapes before you get wrapped up. I'd also recommend running a few test passes with a long steel rod if your spot is shallow enough, just to poke around. Saves you a lot of grinder time.