Still think hydraulic dredges are better than cutter suction for everything

I watched a project on the Mississippi last summer drag on 3 extra weeks because the hydraulic unit couldn't handle the packed sand, even though everyone swore it would. Has anyone else found cutter suction pulls ahead in harder material or is it just me?

3 comments

3 Comments

martin.felix20d ago

Yeah I mean that 3 week delay on the Mississippi sounds rough but maybe it's just me wondering how bad the material actually was. I've seen guys blame the equipment when really the pre-dredge survey just missed some real heavy clay layers. Cutter suction can chew through packed sand better in my experience but then you're dealing with way more downtime for cutterhead changes and pump wear. It's never as clean as the sales pitch makes it seem.

lilykelly20d ago

That clay layer always gets missed 'til the cutterhead hits it, then it's all over.

samjohnson20d ago

That packed sand on the Mississippi is exactly where cutter suction shines in my experience. Saw a crew on the Ohio River swap out their hydraulic rig for a cutter suction halfway through a job, and it cut through the hard stuff like butter after the other unit just sat there churning. The downtime for cutterhead swaps is real, but I've found it's way less of a headache than watching a hydraulic unit bog down and lose all production for days on end. If you've got a good operator who knows when to pull up and swap teeth, the overall pace stays ahead, especially in mixed material where you hit those random hard patches. Your mileage may vary, but I've seen too many hydraulic setups get sold as "all-purpose" when they just can't match the bite in tough ground.

-1