I am brand new to forums so please be kind! We recently moved into a new house with 250' of pond shoreline. The pond is ~40 years old and ~2 acres in size. Our shoreline, though, is very shallow. About 20' out from the shoreline, the pond is still only 1-2' deep. I would like to dredge this out to get a more natural, steeper slope to the pond. My idea is as follows:
1. We have access to an excavator with an extension arm - so we should be able to remove quite a bit of pond muck / sludge from the bottom. 2. Since we have no great place to put the pond sludge, my thought was to pile it up near my existing shoreline to create a flatter sloping edge. Right now (see pics) part of my shoreline is much too steep to enjoy. I would like to "fill" this in with the sludge and smooth out the edge. 3. Eventually if all goes well, the pond would be deeper and I could introduce more fish and submerged plants 4. My shoreline would be more use-able (much less steep) and I could plant native edging plants to give it a softer and more natural look.
My question is - Has anyone ever used sludge to build up, or even create new, shoreline? Will the sludge "fill in" nicely and can I immediately begin to lay seed to get it to not erode back into the pond? I eventually want to put in native pond plants (not just grass) to give the pond a softer and more natural edge.
Thank you for any suggestions / advice! Hope you like the pics and I would be happy to post more pics of any progress! I have already added a much needed aerator / diffuser system to the pond and also added a small beach that my 2 year old loves to play on!
I have used pond muck (or sludge) to fill in low areas on my property and even made the backside of the dam twice as wide as it was prior to de-mucking. It took the muck a full year to dry up enough to be able to work with it. Otherwise is was like pudding. I would not use it as shoreline where it would come into contact with the water. I don't think it would dry at all and would remain much like quick sand and sluff back into the pond. The muck I had pushed to the back side of my dam sluffed off over night during renovation and about a truck load moved 25 feet and had to be dug back up and moved. It was fine and right where we wanted it when I went to bed, but the next morning it had flowed like lava and was not were I wanted it.
I had much of the muck corn-rowed in an adjacent field were it dried for most of a year and then I was able to scoop it up and put it in low spots in my yard. Some smoothing with the tractor blade, hand raking and grass seed...and it is the greenest parts of the yard.
You can certainly reach out and drag the muck out of the pond and gain some deeper shoreline waters, but I don't think it wise to use it at the shoreline unless more clay-like material is brought in to actually be the shoreline. The muck could be used to fill in between the new shoreline clayish berm and the surrounding yard...but it would still need to dry out before it could be handled.
Thank you for the quick and thorough response! And glad to be on the forum!
You definitely raised my biggest fear - that the muck would act like lava and not sit in one place. I even thought about putting in coir logs as well, and then putting the muck in between the logs and my current shoreline - but I think it will ultimately be just too wet to work with or stay put.
I think you convinced me that I definitely need a plan B before we commit to bringing the excavator over
Your muck may not be that thick. You may find that you only have a few inches of the sludge and that what lies beneath it may be more firm clay-like soils. This could help you out. My situation was an 10 foot deep pond that silted in over 50 years and was only 2 foot deep...that was a lot of soupy sludge.
You also need to think about how the pond was constructed. If, for example, your pond basin was littered with gravel veins or sand streaks and it needed a full bowl of clay packed into it...you could jeopardize the water holding ability should you dig through to a porous subsoil. I would have this conversation with a pond expert prior to disturbing the pond bottom. I doubt this is the case, but better safe than sorry.
I was worried about disturbing the bottom as well! That's good advice - I have a contact in the DNR that I will reach out to
On a side note, my neighbors have stated the pond used to be 15' feet deeper or more in certain places...now it's mostly 5' to 6' deep on average. I think I'm going to encounter mostly muck. And with the amount of clay I am dealing with in my yard, one would think I'm living on the world's reserve of clay - so I'm hoping I'm good. But better safe than sorry!
You may be able to get out a few feet with a long wood pole and shove it down into the much to get a feel for depth. The much should allow the pole to penetrate easily, where the base would not. Maybe a 1" diameter with a sharpened tip.
A pond that size that used to have that 15' depth of water that now only has 5-6' of water left is suggesting an enormous amount of muck. I think you will want a good measure of it before choosing next steps. If that volume holds true and you have nowhere to put it all...
My DNR contact confirmed shoving a stick into the muck as well - until I hit the original clay bottom. He also mentioned late September/October for the excavator so I do not cause an oxygen issue - as I would want to wait until the water temp drops. I recently installed an aerator / diffuser system into the pond that runs 24/7, so I think I will be ok, but I will definitely wait for late September just to make sure.
If there is a large amount of muck build up in the pond bottom, and you dig your area of the pond deeper, the muck that is higher in the pond will tend to migrate to your deeper area over time. Like lava flowing underwater.....
JP how did you pond cleaning go? If it was like mine, it didn't turn out as successful as I had hoped... I'm wanting to learn more about dredges now, since even with a big excavator we couldn't get very far out into the middle of the pond... and the comments about a lot of fill, make sure you pay attention to those. I didn't get very much dug out of my pond, but it sure generated a lot of soil to deal with... I'm hoping it will dry in much less than a year so I can get on it and work it down so it doesn't look so rough... I'm a little afraid that the muck that I wasn't able to remove, will now flow into the deep spots I was able to create and I'll be back in need to clean more out of the pond... Guess we'll see... Later J
Based on the commentary in this forum I decided against plan A. The slope of my yard was just too steep to hold the muck - I felt it would just slide back into the pond like lava and create an even larger mess/buildup on my shoreline. I am starting to communicate more with my neighbors and hopefully a majority of us can align on a plan to dredge it out properly next year. Our new neighbor has an empty lot across the pond and he is willing to put the muck on his lot where he needs to build it up.
For now, enjoy a pic of the diffusers at work that I added this year!