My back yard is wet pretty much year round. Just to the west of my back yard there is a pond/swampy area that fluctuates maybe 6-12" depending the time of year. However in the 4 years I have lived here it has never completely dried out or flooded. I'm guessing it's only 2 or so feet deep. The transit showed my back yard is only approximately 6-12" above the water level of that pond/swamp. The 2 excavating companies I have had out both felt I am right at the water table which is causing my yard to be wet year round. I am having approximately 2,000-3,000 yds of fill trucked in this summer to raise my yard and hopefully fix the problem. One desire I have however is to dig a pond on the east side of my yard to help with some of the fill and to possibly stock with fish. It will be around 75'x100' in somewhat of an oval shape if done and around 8-12 ft at the deepest if the slope will allow it.

I would then like to french drain my back yard into the pond. Since the swamp/pond to the west has never flooded or dried out in the time I have lived here I am assuming the new pond will naturally remain the same level as well...??

Another question is will I have major problems trying to dig a pond that is at or near the water table? I could pump the water out as I dig however since we are already in a low spot I don't have too many options on where to pump the water to.

Also there is an extreme amount of sand in my area. I will dig test holes first but if I actually do hit sand will this be a major issue? Since I am relying on the water table to keep my pond full I wouldn't necessarily think I want to clay line it but not sure.? However if I don't line it I am under the impression the pond will simply fill itself in over time. If I do clay line it how will the water enter the pond to naturally keep it full?

Another thought I had was put in a drain tile from the existing swamp/pond to the west and allow both sites to equalize themselves.

Any advice you could give would be greatly appreciated.

I have (hopefully) attached a picture of my back yard for reference. The existing pond/swamp is out of the picture but on the right side just past the trees. The area for the new pond I would like to dig is on the left side of the picture just off the grassy area.

Thanks again!

A few random thoughts and questions.
1 It seems unlikely that the true ground water table is that high in Ohio. I would guess there is a shallow non permiable layer of clay in that area causing the surface water. If that is the case, digging through the clay layer may drain the area, good or bad.
2 How big is the wet area?
3 A pond can be easily dug with an excavator in a wet area, it doesnt matter if it fills as it is being dug.
4 If you are raising the yard, why bother with the french drain? Can you just build a gentle slope for drainage?
5 you may want to check with Local NRCS office or website and look at the soil survey of your area, it is not exact but may be a start in understanding what you are dealing with.

I had a low spot in my yard with lush grass but no standing water. I took a skid steer and dug down 3 feet. It filled with water and stayed full all summer. This is ground water in sand. There is 8 feet of sand on top of good clay in all the surrounding area. So I dug a 100x180ft and (12 feet at the deepest) pond with a 300 excavator while the pond was full of water. It is a challenge and dangerous to dig unless you have a good pump to keep it low. You might need to dry out the spoil piles for a day or 2 before you try landscaping it out. I had to move my dirt about 150feet with my excavator. It took me 40hrs to finish the project but less then half that time was actually digging.

I got on the NRCS site and found my AOI. It was a pretty interesting site. I had no idea that existed.

To answer a few of your questions:
1 According to the NRCS my back yard appears to be right at the water table (if I'm reading it right).
2 The wet area is maybe 1/3 of an acre + and is oval shaped. There are several other similar wet areas within a fairly close proximity to our house as well.
4 I had planned to grade the fill dirt to the pond without a french drain initially. I figured I would ad the drain as an afterthought if necessary.

**Also based on the picture do you think I will have issues with the number of trees that will be around the pond? It will get direct sunlight in the afternoon hours.

This is what I found found from NRCS:
This description area actually only encircled the area I want to build my pond, my back yard, and the existing swampy/pond area to the west side of our yard. All the surrounding areas including my house were listed as sloped areas that are well drained.

I would be very interested in what some of you guys think as far as digging in this spot.




Stark County, Ohio
Ch—Carlisle muck
Map Unit Setting

Elevation: 600 to 3,700 feet
Mean annual precipitation: 28 to 42 inches
Mean annual air temperature: 46 to 54 degrees F
Frost-free period: 110 to 195 days

Map Unit Composition

Carlisle and similar soils: 100 percent

Description of Carlisle
Setting

Landform: Depressions
Parent material: Herbaceous organic material and/or woody organic material

Properties and qualities

Slope: 0 to 2 percent
Depth to restrictive feature: More than 80 inches
Drainage class: Very poorly drained
Capacity of the most limiting layer to transmit water (Ksat): Moderately low to moderately high (0.06 to 0.20 in/hr)
Depth to water table: About 0 to 6 inches
Frequency of flooding: None
Frequency of ponding: Frequent
Calcium carbonate, maximum content: 30 percent
Available water capacity: Very high (about 13.8 inches)

Interpretive groups

Farmland classification: Not prime farmland
Land capability (nonirrigated): 3w
Hydrologic Soil Group: A/D

Typical profile

0 to 60 inches: Muck
60 to 80 inches: Variable

Minor Components
Willette

Percent of map unit:
Landform: Depressions

Linwood

Percent of map unit:
Landform: Depressions

Ginat

Percent of map unit:
Landform: Rises


Thank you again for your time!!

It apears you have a clay layer with sand on top of it, the sand is holding the water. Most of Ohio was scoured by glaciers and they leave behind many layers of different material, you never know when one layer will start and another ends. I would think you can get a pond dug with out problems and as long as you do not dig through the clay layer, and you are correct the pond should be filled slowly or quickly by ground water. Whenever you put a bucket in the ground you never know for certain what you will find but if your contractor knows what he is doing he can tell by the material coming up what is going on with the soil.

That sounds great. Thank you for all of the advice!!

I'm not sure that is the best thing to do -- I believe he usual advice is to dig down to the sand if you have good clay, and then pack the clay back on top with a roller. Send a message to Esshup!

I have a groundwater pond. 11' of sand on top of 1' of clay, then another 6' of sand on top of at least 4' of clay. (when we renovated the pond we dug down to 22' below grade and it was solid blue clay there). In a wet spring, water will sit on top of the ground until early June.

What I've found over the years is that the groundwater level will fluctuate up to 6'. During a wet year, the pond will drop about 3'. In a dry year, double that.

If I were to do it all over again, even though I put the pond in a wet spot, I would dig the pond large enough so I could line the whole pond basin with 6" lifts of clay, compacting each lift with the next one so I would end up with at least 2' of compacted clay.

I can pump 25 gpm of water into the pond and it will not reach full pool during drier years. I've never run the well during a wet year, saving on energy costs and just figuring that a 3' drop in water level was normal. If I had my druthers, I would rather have the pond full at all times vs. fluctuate in water level.

My neighbors, who have lived here about 10 years longer than I have, said that with me having the pond, they see less flooding in their back yard during wet times of the year. So, when you dig your pond, you may not see the water standing on top of the ground like you do now. The way my pond is designed, it will receive surface (top of ground) water runoff.

In hindsight, if I would have only dug the pond 11' deep so I didn't punch through the level of clay, I would end up with a pond that at least 6 months out of the year would be only 5' deep at the most. That depth is not conductive to having fish survive a long and hard winter like we just had without intensive management methods. I dug the pond down to the 22' deep mark, and normally go through a winter with 14' of water in the deepest part of the pond.

Thanks for the info. Sorry it took me a bit to reply but everything you've said seems to apply to my situation. The only thing I can say that might be a little different is the fluctuation in the water table. One thing I've noticed in the 4 years we've been there is the swamp on the opposite side of my yard never seems to vary much more than 2 or 3 ft. It actually only seems to be a few feet deep and I have never seen it dry completely up. Is it possible for the water table to only fluctuate that amount in both dry and wet seasons? If so I can only assume my pond will hold water in the same manner? If so I don't think that small amount of fluctuation would bother me much. If it were like your situation with several feet of variance in water levels I would probably prefer it to be lined as well.

Another question I have is if I were to clay line the pond how would all of the water in my yard drain to it? Wouldn't the clay lining not only seal the water in the pond but also seal the water outside the pond? If my back yard sits right at the water table wouldn't that defeat my purpose of giving it all a place to go? How would I keep it full of water? Also if I were to just dig a groundwater pond what type of soil do I need? I assume it could be anything but preferably a porous material to allow the ground water to flow into it? If I have a lot of sand in my soil how do I prevent it from simply filling in on sitself? Also if you look at the picture in the initial post you can see trees surrounding 3/4 of the sides where the pond will go. Do you think that would be a major issue? I plan on cutting down several of the ones close to where the banks will be.

I apologize for the amount of questions and I really appreciate everyone's input and advice. If I'm going to shell out this kind of money I just want to make sure I get it right the first time. Thanks again.

Yes, if the swamp is the low spot in the surrounding area. Any water that is in the ground runs to it.



Maybe. If you dig the pond, you have to remove soil. Now your pond area will be just water, not water and soil. So, your pond might not fill up all the way, depending if there is enough water to make up for the amount (volume) of soil that is removed.




Surface run-off.

Yes

No, make the top level of the pond lower than your yard and the water in the yard will run into the pond.

If the pond is sealed well, then you'd have to make up for evaporation losses if there is no surface water running into the pond.

Whatever soil was on the property.

Make the slopes in the pond no steeper than 3:1. 4:1 is even better. Get the soil covered asap after digging with rye grass, whatever groundcover you want to be permanent and erosion mats.

The more organic matter that falls/blows into the pond, the more muck accumulates and the faster the pond "fills in".

Wouldn't the water find its way in no matter how well you might seal with clay soil?

Water could find it's way in, but the reason that you seal with a good clay liner is to keep the water in the pond. If the liner is constructed correctly, I doubt that you could definitively say "that came thru the liner".

On the NRCS site what does "Depth to Restrictive Feature" mean? In my area it says 80 inches. Does that refer to something like clay that restricts water flow?

Also if I dig deep enough for fish what type of cover do you want to put in the pond for them? My pond will have a fair amount of trees surrounding it so I'm guessing every 5-7 years I may have to dig it out and clean it up. Is there an easy way to address that issue and keep my fish and cover healthy in the process?

Yes.

To answer your cover for fish question, read this. That should help.

When I dug my 1/10 acre pond it was in blue clay. The excavator smoothed out the whole surface to seal leaks but I didn't have to worry about water leaking out cause the water poked it's way through the clay and the pond filled on it's own. My water table is about 24" from the surface. But the pond has filled to the top. We had a ton of snow this year and all the runoff seems to have gone into the pond cause even with all the extra snow the surrounding area was drier than it was last year.(I just dug the pond last fall) My theory is that since the pond level is now higher than the water table, the clay must be containing the water near the top, but the pond may drain down to water table level. Time will tell, and good luck with your pond.

Eric2726

I am also currently digging a pond in stark county and have similar soil map readings and would love to know any tips or issues you have. If you could email me at djs480@yahoo.com