I have a field water drainage problem where I keep my horses. What is the best solution to eliminate the resulting problem of "ponding" at 4 different areas of about 7 acres total of horse grazing area? I have a clay soil with a high water table. FT
Clay holds water, obviously, but water does slowly seep through it. Clay makes good lining for ponds - you have four of them - they probably vary in depth from time to time.
One expensive yet effective solution is to hire an excavator to dig one large pond and use the removed clay to fill in the other three low areas. Since the one big pond is going to be much deeper than any low area you have now it should hold a large enough amount of water for fish (perhaps trout) and ducks. Ducks look good around horses.
Since this is a solution you have probably already thought of, it may not be the one you are looking for.
Compacted clay also makes a decent bed for gravel, perhaps you could line the perimeter of the new pond with gravel so the horses have good footing when they come to drink.
Although I am a mechanical engineer, I grew up on a small farm with horses, ducks, etc. and ponds are a very nice feature to have on small farms.
You may get lucky and discover gravel beneath the clay if you dig deep enough which you can use to line the perimeter. And if you are really lucky you may discover a spring in the gravel which would ensure fresh water for your horses.
Without looking at the topo for your field I can not give a definitive answer. A suggestion is to tie the low areas into whatever natural drainage your field is a part of through gentle swales. You have to be careful that you do not move your problem to your neighbor's land.
You can drain it, enmass it, or leave it. I live in central western Canada where we'll take it if there was a way to get it here. If you want to alter the condition, you'll need an accurate topographical map of your property. I would retain the water unless you are assured of continued percipitation for your pasture. Evaluate the course of natural drainage off your property. Is the surface level of this course higher of lower than your objectionable ponding levels. This will tell you the extent of control you can exercise. Now consider grading a sloped bank trench that would consolidate the ponding that is higher than this level and contain it with a damn. Gradually spill what you don't require over a period that wil not cause undo erosion on neighbouring parcels. Don't forget to cost in the stripping back and refill of your top soils. Plant the resoiled area with grasses and water well for quick growth, soil retention. If you have no drainage ability, you may still consider consolidation into a single deeper pond. I would stongly recommend that you speak with one of your local gov. agricultural specialists for your area. You may expend a lot to consolidate into a deeper pond, only to discover you now have increased your water holding capacity and your ponding area hasn't changed.