Pasture Drainage

Well, within the past year I have done two separate projects to drain fields. One in a crop area and one in a pasture.

The basic process is ditches were dug down to the watertable - 3-5' deep with a backhoe. In both cases, the pipe empty into a low drainage area or existing ditch. In first project 6" plastic perferated pipe was used and in the second 4'. If I had to do the first one again, I'd use two 4' lines as it would be about 50% on price for the pipe. The trenches were then backfilled with creek gravel to the surface and the dirt which had been removed from the ditches spread sideways - not covering the tops of the ditches.

In both cases stakes with flags were put into areas of standing water. The backhoe then dug a long ditch or ditches and basically connected the dots. Both areas have dried up fine.

In the second project fully loaded large gravel tracks were crossing area where previously a tracked vehicle, such as a bulldozer, would have been required this time of the year. I could only bushhoe all of this field about once a year during the driest period of the late summer.

Figure $3 per foot of trench as a rough guide if you use the above. You can somewhat save money but not putting gravel in the entire ditches, such as low areas so they drain into the bottom pipe. The areas of the field where it is solid now can be backfilled with the dirt which came out.

Ken S. in WC TN

 

Ken's reply is accurate as to the permanent fix. Contact your local extension service or soil conservation office. they will come out and help you plan what needs to be done.

 

I was just reading about pasture drainage the other day. The whole idea behind draining a pasture is to keep water from running onto the field that doesn't need to be there. You don't want all the water from uphill of the pasture joining the water that's already in the pasture. Building a ditch on the uphill side will prevent this by carrying water to the edge of the pasture rather than letting it add to the water that's already there. There's no point building a ditch at the bottom of the field because by the time the water gets there, it's out of the field (unless there's another field beyond that of course). Depending on the size of the pasture, you could build a reasonable number of small ditches following the contours of the land. Doing so will further break up the pasture into smaller sections, reducing the amount of water that needs to be soaked up by the lowest section. If the pasture is flooded because the water table is really high due to spring runoff, building ditches may be difficult to do until the water level drops, but it may help drain the pasture faster next year, and will certainly drain it well the rest of the year. I hope this helps.

 

I think I can illustrate Beeman's point with my pasture drainage project. Image a sheet of paper held sideways. Across the top draw a line from left to right. Draw another line from the middle down to the bottom. On both sides of this T put a U connected to the top line and coming close to the center line.

The top of the T is an existing WPA ditch. The centerline is an old roadbed. The U's represent the ditching. There is a slope of maybe a foot from left to right and that is also the direction of underground water flow.

The U on the right was dug first. Water stopped flowing in it within about two days. On the left U, the left half of it continued to have water flow while the right half dried up within a couple of days. That rather tells me if I had only done the left half of the left U, it may have caused the rest of the field to dry up naturally as it cut off the flow of water.

Ken S. in WC TN

 

So, what are you trying to accomplish with the drainage? Is this just a spring run-off issue? then do _not_ waste your time. These wet areas will be your most productive during the hot summer months. and you can't run livestock on your pasture until it grows a foot or so, long after the rainy season. so drainage in that case would be a total waste of time & money 7 possibly reduce your production to boot.

My pasture has a county ditch running past it, and is a pasture because it is too low to drain & plant crops in it. Every spring there is foot of water in it for a week or more. Heavy rains will make ponds for a few days. They drain away on their own. so long as it doesn't stand long enough to drown your grass crop, it's a good thing - charges up the ground for the long hot dry spell.

My advise is leave well enough alone.

On the other hand, my farm land has miles of drainage tile in it. So I'm well familar with tile, & the need for it. if you actually need to drain the wet spots because it is killing your grass, then I would suggest 'grassy waterway' instead of shallow trenches. The trenches even with junky tiles in the bottom will not work well. Deep perforated tile below the frost line is great tile, but you don't seem to need that. A wide shallow grass waterway would give you drainage, not mess up your pasture, and require no future maintenence or special upkeep. Only difficulty is establishing the new grass in them before a heavy rain that would wrech them....

Please write back with your needs, I could write for hours about drainage, dad used to survey tile lines and in my rolling hills & the peat bog I farm I'm pretty familiar with it! but don't want to waste your time with stuff you don't need.

I kinda think you are best off doing nothing, but don't know the full situation.

--->Paul