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pinksand
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River rocks sinking into boggy soil

For more details, I’ve already posted on the subject here viewtopic.php?f=8&t=64825

To summarize the issue… We have a natural spring that supposedly starts on our neighbors property and feeds into our front yard. This area was previously lawn that I converted into a bog/rain garden. To help the water flow down a desired path and keep it off our driveway, I dug a trench and put down some 1-4” river rocks. Ordinarily with a dry river bed I’d lay down some kind of barrier (plastic, etc) under the rocks. However, because the water literally trickles down these rocks at times I didn’t think a barrier would be appropriate. Unfortunately this has resulted in the rocks in the muddiest zones sinking into the ground as the water flows and pushes the mud around the rocks. Earlier this year we bought a few bags of pea gravel and mixed them into the 1-4” river rocks, but they’re still getting mixed with mud.

Overall, the water is being diverted appropriately and flows through the drainage tubing under the driveway and into another rain garden. However, it looks a bit ugly having an odd mud pit flowing down the middle of a section of the dry river bed (though it’s never really dry).

Do you think that digging up the rocks in that section (hosing them off), adding sand and a more substantial layer of pea gravel, and then hosing off the removed stones and putting them back on the layer of sand and gravel would help keep it from being such a mess?

Any other thoughts or tips?

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applestar
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If you are digging them up, I'm thinking what you want is something to let the mud/silt sink while leaving the rocks above. What about some kind of non-corrosive mesh?

Otherwise, only thing I can think of is to put down bigger rocks (or even pavers) that can act as the base even if they sink, then put the smaller rocks on top.

imafan26
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. I do suggest you use different sizes of gravel and rocks so the smaller pieces can help lock the larger stones. If you look at a river bed, silt is deposited where the stream is weakest, along the meanders. There are very little small stones where flow is heavy since they get washed away. Only the heaviest stones will stay in place, but mud and small stones will be behind it. Since the mud collects there, it must be where the flow is also the weakest or it allows pooling for the mud to collect. You could dig it deeper and put in a screen that would drain the mud and leave the rocks on top. The mud would still have to go somewhere or you would have to put a catch basin under it and clean it out when it gets full. The mud may not be coming from that point but it being washed down by the ground above it, in which case you could do some rerouting and creating a meander to collect the mud and let the water flow around it. You would have to dredge the meander if the silt build up gets too big.

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ID jit
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I read the other post and this one.

Your neighbor has a spring which is re-springing in your yard and causing a mud pit.
Down stream from the mud pit is your driveway and then a rain garden.
Excess water in the winter makes your drive way a slide way.
Stones you are putting in are sinking out of site.

You have a "seep", a low volume artesian spring. Not a whole lot of options. give the water someplace to go or have a mud pit. Dry season you thristy plants will not do so well and wet season they won't be soaking up enough water fast enough.

To me, the simplest solution is a trench, some gravel or 3/4 stone and 4" perforated drain pipe and use the mud hole water to feed the rain garden on the other side.

If you want something to grow and play with, a grass bottom or koi pond would work with the overflow feeding the lower rain garden.

Otherwise, drop a spring box and a clapper valve pump on it or put in a shallow ground water well and water your lawn and garden.

Not so long ago, seeps like you are describing were tapped, run together and used to dry out boggy section of pasture and water dairy cows.

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pinksand
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ID jit wrote:I read the other post and this one.

Your neighbor has a spring which is re-springing in your yard and causing a mud pit.
Down stream from the mud pit is your driveway and then a rain garden.
Excess water in the winter makes your drive way a slide way.
Stones you are putting in are sinking out of site.

You have a "seep", a low volume artesian spring. Not a whole lot of options. give the water someplace to go or have a mud pit. Dry season you thristy plants will not do so well and wet season they won't be soaking up enough water fast enough.
Did you read the follow up posts? A lot of what you've mentioned has fortunately already been resolved.

I think it's a bit hard to explain without seeing it in person... There are gardens on either end of the driveway and with the trench and stone work in place the water now flows under the driveway from one garden to the other, not across the driveway, so there's no longer an ice rink in winter. The water does have a place to go and dissipates and dries on the other end between the garden, lawn, and a gravel/weedy section at the bottom of my other neighbor's yard. So far the plants in both gardens have done very well for a couple of years now so that's not an issue at this point.

I should have mentioned that the muddy section where the stones are being engulfed by sludge isn't at the bottom, it's at a steep section towards the middle where the water is most visibly flowing. Our front yard is very steep (people huff and puff up our driveway and joke about needing a rope toe when it snows). The very bottom of the garden is nothing but rocks up to the street and is never sludgy.

I like the idea of some kind of mesh that will allow water through but help block some of the mud/soil... does that exist and does it have a name?

At the top of the rocky trench I actually laid broken bricks as a base layer, sort of in line with what you're suggesting applestar. I ran out of bricks though :( it's such a sloppy mess I'd honestly almost rather pile rocks on top instead of trying to dig them out of the mud... I almost lost my boot to the squishfest when I initially worked on the trench. SO MESSY!

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ID jit
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pinksand wrote:Did you read the follow up posts? A lot of what you've mentioned has fortunately already been resolved.
Believe it or not, I did.

The mud filter your are looking for is a 4'x4' (or bigger) hole in the ground filled with sand and pea stone with a 6" - 8" perforated pipe down the center to tap for clean water and a blow out at the bottom to flush out once or twice a year. I may be wrong, but until you get the water out of the silt, all you are going to accomplish is moving the mud pit farther downhill or down stream.

Not a key board warrior looking to pick a fight. When I was a kid old enough to work until my late teens, I was sent on 'vacation' to my uncles' dairy farms in the Northeast kingdom of VT. After the fun of clearing pasture and throwing hay bales came building or rebuilding spring boxes and running miles of 2" irrigation line to replace the rusting out black iron pipe which was used to dry up mud holes in the sloped pasture. After that was repair to what was in essence a giant leach field which directed the N rich waste water from the cows into hay fields and a sugar wood so it wouldn't contaminate the river in the bottom of the valley. Almost all of those spring boxes were sitting on top of seeps just like you describe.

Was trying to be helpful even if I am presenting a solution you would probably prefer to be different. Once you get the water to a clear state, it is a whole lot easier to manage, and will follow any stone trench you drop in front of it.

Good luck with it.



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