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Dealing with flow bubbles affecting vision underwater


#1

Anyone have any tips for dealing with bubble clouded viability underwater? Where water comes rushing over rock in front of you it fills the water with bubbles making it hard to see what you’re doing.

Maybe take s piece of board and wedge it in rocks to try and divert the flow a little?

Curious if anyone has any methods they use to deal with this when pushing forward against the flow.


#2

If that is the creek you were working in your last post I would have started the day by de-rocking, that is moving all those small but lift-able boulders out of the way either onto the bank (detect first) or behind the dredge, build yourself a pond to work with.
It’s laborious but none of those boulders are going to go up a 4" nozzle and its nice having a bit more depth between the nozzle and the surface when working with a powerjet dredge.

Looks like an good piece of ground to work by the way, you are certainly not going to have issues with a want for water and it has the look that bedrock will not be too far beneath you.


#3

Yes, it’s a nice wee creek to work :slight_smile: Half the problem this time was that the bedrock was shallower than expected so I ended up pushing further than originally expected for the weekend. Started to force me into current to progress and I’d not been throwing the rocks further enough away and a bit of bad planning. Just below me the bedrock had been deeper so I expected the same.

Still think I’ll be encountering bubbled water though due to the fall of the bedrock in some places so will be interesting to hear any ideas. I used my forearm over my head to some success for a while, but got tedious.


#4

Hi Gavin

Try putting a bit of a dam in behind you, slightly downstream from where your dredge is discharging.By lifting the water level you will get rid of the racy bubbly water, the downside of that is you may get a little murking out. If you do get back to me, there is an easy cheap way to deal with that. Damming is easy, rock wall, then lay black garden plastic on the inside. When you get into that gorge bit. You can do even better and really raise the level. By using a fallen over tree trunk. Some down stakes, cyclone fencing and black plastic. Or lug some pipe in to take place of the tree trunk. Lets keep it green lol. Those small creeks are a pain in the arse to work, unless you utilize the damming method. Frig I have raised them 6 feet no problem. Easy to start the hole, plenty of water to float the dredge, plenty of room for tailings.Damming is the way to go. If you want more info just ask. I got rather good at it. De murking is real easy.


#5

Ah, I like the plastic idea - that sounds easy enough and I can see it being effective. Some heavy duty plastic so it can take some serious rock abuse.

I tend to work above the dredge so haven’t had an issue with things getting murky yet. Not a great deal of dirt in the sediment so tends to run clear anyway. But I can see how it might become something I need to deal with if damming.

Intrigued by the damming idea. If I get myself in there for a week straight then I’ll give it a go. Not sure it’s worth the effort on weekend missions as good chance there’s been some rain while away from the river between missions which would probably undo my work. Been really suprised from week to week when I’ve returned and my deep holes are completely filled as if I’d never been there, and that’s without any rain as far as I’m aware.

Any photos of your damming escapades you can share? And quite curious about the de-murking suggestions you have. Would be good to squirrel away in the back of my mind in case I need them :wink:


#6

Hi Gavin.

The dam doesn’t have to be high, a few of those larger boulders across the creek will do the trick.
Would take less than 15 minutes, and be there after a flood. When finished dredging you just take the plastic home with you, or leave it somewhere on your claim. The moment you put the plastic film in the water,it will cling to those rocks like glue on wall paper. The higher your dam, the further up the creek you can dredge with no problems. I used to dredge plenty of creeks, and every time I used a dam, makes the dredge float to. One thing I found with creeks. On starting the hole best to chuck every stone you can up on the bank,that way you pretty soon have deep water to pull the dredge into and the dam to help you along the way.

Right the anti murk net. Bit of a cunning one this and thought out by me. After many murking problems.in small creeks. This is what I used, but you could improvise I guess. I used an old fishing net .First thing I did was cut the net away, as all I wanted was the top rope with floats on it, and the bottom rope with lead weights on it .I cut of a section of the two ropes, long enough to go across any small creek,but really making it a bit longer doesn’t hurt, as the surplus can just lay on the bank. Right then off to Mitre Ten and buy a length of shade cloth or weed clothe. As long as it has very small aperture’s/holes in it, smaller the better. (Tight Weave), then bought some clips, which are also in the garden section. Right attach the cloth to the top and bottom section. Done, you now have an anti murk net. It will allow the water to flow through. Set up your dredge in your hole, and somewhere along where your suction hose is laying on the creek bed bottom. Lay the anti murk net across it. from bank to bank. The top rope will float, the bottom rope will lay snugly on the rocky bottom. With your suction hose sticking out. Dredge away, any murk no matter how stagnant your pond is, will stay on the other side and not come through. The flow through the cloth will ensure that. But even with no flow, very little murk will migrate through. Dredge away happily. Move when required. And there you have it Gavin.


#7

Sounds like you’ve shared a few gems of advice there - very much appreciated! I must admit I’ve been chucking my rocks over to the other side of the steam most times as figured floods would just wash it all away but I think I’ll have to try chucking as much as I can on the bank - makes sense, as blocked my progress last trip when the bedrock wasn’t as deep as expected forcing me to expand hole and I was only chucking as far as middle.


#8

Interesting, here’s someone using plastic sheeting to create a dam…


#9

Hi Gavin

I wondered what he was up to at the start of the vid. And then it dawned on me. I was wondering where is his suction nozzle. And then bugger me. He is using the siphon method. Not enough suction to move the rocks, but the finer stuff only. Ingenious, in a very little fall river like that. He uses the dam to achieve it.
Must have cost him a fortune for that rather long length of suction hose. I note he has the plastic then rocks behind it. I only ever just laid the plastic at the back of the dam. Suction then just makes that plastic cling like nobodys business.

Cheers Trev