I live in ireland. in the field next to my parents house, it gets waterlogged at a certain site. once the rain stops the water does drain. But i guess the water table here is higher or there is slightly more clay in that area. it looks like this, below while raining and then below again after a night without rain.
I want to make this area a 'natural pond' without a liner. the soil here has lots of gleying, i presume that means the water table is high. what can i do to make it hold water in this area?
should i dig deeper? should i do a soil test around here or is it all going to be the same and cant be improved anyway? should i be 'gleying' the soil with horse manure?
any tips at all would be great. we get lots of rain here
(I don't know any of the pond/water diversion regulations in Ireland, so make sure you follow those rules BEFORE following any "technical" advice you may receive on Pond Boss.)
I can't tell from the close-in photos if that is surface water run off that has pooled in a low spot, or if it truly groundwater due to a rising water table. Can you examine the lay of your land and make a determination? It doesn't take much of a slope or much of a depression to collect water like that.
Your gleying is a good sign that you probably have sufficient clay to make a sealing pond (if the other conditions can be met). Even when there is good clay present to keep the soil horizons water logged, there may also be some sand/gravel layers present that also affect the water flows. These layers, or even just stringers of sand, must be disrupted and sealed if you are going to attempt to make a sealed pond.
Is the "field next to your parents' house" a working farm or rural property? (That gives you more room to develop your project.) Do you have any excavating equipment on the property?
I would just start digging with a shovel when it is dry at that location and see what you get. If the soil is still damp, then you should be able to make a ball in your hand if you have sufficient clay. If you can start to roll the ball into a "worm" then you have really good clay. If you can excavate with equipment, then keep taking samples on your way down. Eventually, your sample trench will probably start to fill with water. If it is safe (from humans and animals), you might leave the trench open and keep some records of the water level.
If it is surface water collecting in a depression AND you have good clay, you can easily make a nice, little pond there. If it is groundwater, that is a little more complicated, but you also have several options that might be able to create a nice pond there.
Can you give some dimensions of the potential pond? (If you work in metric only, post it in metric and I will convert.)
(I don't know any of the pond/water diversion regulations in Ireland, so make sure you follow those rules BEFORE following any "technical" advice you may receive on Pond Boss.)
I can't tell from the close-in photos if that is surface water run off that has pooled in a low spot, or if it truly groundwater due to a rising water table. Can you examine the lay of your land and make a determination? It doesn't take much of a slope or much of a depression to collect water like that.
Your gleying is a good sign that you probably have sufficient clay to make a sealing pond (if the other conditions can be met). Even when there is good clay present to keep the soil horizons water logged, there may also be some sand/gravel layers present that also affect the water flows. These layers, or even just stringers of sand, must be disrupted and sealed if you are going to attempt to make a sealed pond.
Is the "field next to your parents' house" a working farm or rural property? (That gives you more room to develop your project.) Do you have any excavating equipment on the property?
I would just start digging with a shovel when it is dry at that location and see what you get. If the soil is still damp, then you should be able to make a ball in your hand if you have sufficient clay. If you can start to roll the ball into a "worm" then you have really good clay. If you can excavate with equipment, then keep taking samples on your way down. Eventually, your sample trench will probably start to fill with water. If it is safe (from humans and animals), you might leave the trench open and keep some records of the water level.
If it is surface water collecting in a depression AND you have good clay, you can easily make a nice, little pond there. If it is groundwater, that is a little more complicated, but you also have several options that might be able to create a nice pond there.
Can you give some dimensions of the potential pond? (If you work in metric only, post it in metric and I will convert.)
Good luck on your future pond project (I hope)!
Many thanks for the input. It's a good question re surface run off vs groundwater. I suspect it's actually surface water run off as, on closer inspection, this area of the field is in a slight dip.
This field is not a working farm, simply a field which houses a single horse. It is not used agriculturally or for anything else. I do not have any excavating equipment.
I think that's a good plan, to just dig when it eventually tries here. Do I understand correctly that you sort of recommend that I keep digging until the soil seems to reach a point where there is more clay? Is it correct at all to assume that there is more clay the further down you go, generally speaking?
I guess if I stop and it rains and it doesn't hold anything I can either keep digging or else just fill it up and try elsewhere.
So surface water is a better prospect? Seems like good news. The dimensions would be very modest initially, as a trial, maybe 2.5 feet deep and 5 feet long and maybe 4 feet wide.
Those dimensions are tiny. Is that all that you need for your projected size for an adequate wildlife pond?
Sometimes making the pond a little larger will enable you to retain a little more water in the pool during the dry season.
If you are finding some clay during your "shovel test", then you may want to rent a mini-excavator. I can get one for about $350/day in the U.S. If you could get one, then you might be able to get a decent pond in a single day.
If the depression seems to "drain" faster than just evaporation then you probably do have some type of natural leak. Typically, it is plant roots (either current or decayed) or depositional layers of sand/gravel that provide the water flow routes through an otherwise mostly clay soil.
I would probably strip the grass and best topsoil off of an area of higher ground where a berm/dike would contain the most surface water from flowing past the area of your pond. Dig out the pond and put that material in the berm area to increase its elevation. Then re-cover the berm with your saved topsoil.
You need to save some of your best clay by the pond to line the bottom and the sides. (Especially if you see some well-defined layers in the sides.) After making a 6"(?) thick clay liner you need to moisten the clay and then compact. Maybe by hand with a heavy tamper, but renting a vibratory plate compactor might work better. The good news is that since your pond is only 2.5 feet deep, there will not be much hydrostatic pressure trying to cause your seal to leak!
Hope that gives you some ideas for the job. It is difficult to give good advice from far away and without being able to see the actual soil you are dealing with. Perhaps some other members will chime in with some improvements over my basic advice!
Those dimensions are tiny. Is that all that you need for your projected size for an adequate wildlife pond?
Sometimes making the pond a little larger will enable you to retain a little more water in the pool during the dry season.
If you are finding some clay during your "shovel test", then you may want to rent a mini-excavator. I can get one for about $350/day in the U.S. If you could get one, then you might be able to get a decent pond in a single day.
If the depression seems to "drain" faster than just evaporation then you probably do have some type of natural leak. Typically, it is plant roots (either current or decayed) or depositional layers of sand/gravel that provide the water flow routes through an otherwise mostly clay soil.
I would probably strip the grass and best topsoil off of an area of higher ground where a berm/dike would contain the most surface water from flowing past the area of your pond. Dig out the pond and put that material in the berm area to increase its elevation. Then re-cover the berm with your saved topsoil.
You need to save some of your best clay by the pond to line the bottom and the sides. (Especially if you see some well-defined layers in the sides.) After making a 6"(?) thick clay liner you need to moisten the clay and then compact. Maybe by hand with a heavy tamper, but renting a vibratory plate compactor might work better. The good news is that since your pond is only 2.5 feet deep, there will not be much hydrostatic pressure trying to cause your seal to leak!
Hope that gives you some ideas for the job. It is difficult to give good advice from far away and without being able to see the actual soil you are dealing with. Perhaps some other members will chime in with some improvements over my basic advice!
Many thanks. yes, the dimensions are very small, you are right that it should be bigger, but at the moment I'm trying to start small and, since it's a seasonal pond right now that seems to dry up, maybe i can dig it a little bigger when it dries.
I have been observing it the last couple of days and we have had a LOT of rainfall. The water has really pooled in that area and has created a sort of biggish natural seasonal pond oer the surface of the soil. Lots of birds have been coming to wash their feathers which has been great. I am now waiting for it to dry a bit so that I can dig more and hopefully even reach some clay.
If I never find a truly good clay layer then I guess I may as well just dig it out and even if it is 'just' a seasonal pond during rainy season then that's still better than nothing I guess. It rains a lot all year round here anyway. I don't want to use a liner as it costs a lot and also I like the idea of a natural area.
I really like your idea of making a berm to contain some of the run off. I will do that when I dig it out a bit more.
Actually, if you stay with the "small pond" dimensions, a pond liner is not that expensive at all. It would be small enough that a single person could do the installation with no heavy equipment. Labor and equipment are a large percentage of the cost on big installation projects. Another option would be to buy one of the pre-formed decorative pond basins.
With either style, you could make an attractive pond feature with a small waterfall or aerator, and rock edging to match the style of your rural setting. Wildlife would still use such a pond. And you could add frogs, goldfish, etc. (Although the wildlife may "enjoy" your additions.)
In that case, I would move such a pond away from your low spot. I would put it on higher ground, wherever it most suited your view.
The good news on that type of project, is that you can always make additional modifications at a later date if it doesn't quite suit your needs or the wildlife's needs!
