Round pen drainage

[Schneeky]

Hey guys. We're puttin a round pen in the pasture for workin/training the horses. Got a coupla questions.
I've prepped the site pretty much. Scraped off a 64' circular base from 8"-12" deep. We got a good rain and it's got plenty of grade but the sticky red clay at the bottom holds the water. We'd like to keep the passage between the perimeter fence and the round pen usable for vehicles. Is it as simple as putting in a small pipe? Would that clog up over time? Other suggestions?
..Also, what recommendations would you have for footing? Seems there's a whole lotta differing opinions on that. We're in central NC if that's relevant. Are geo textiles of any use in that application. We've heard it both ways.
..Thanks much for any helpful advice!!

 

[ROUSTABOUT]

Same loads of sand

 

[riptides]

I'd stick some drain tile and gravel where you have the water issue. Take it outside the perimeter fence.

Are you planning on fencing off the round pen? Or are you leaving it in the pasture area?

We used about 10 truckloads of stone dust.

 

[Egon]

A shallow drainage trench with the whole circle sloped to it.

 

[Dragonpharm]

I will be putting in a round pen myself very soon. For several years we have shared a round pen with the neighbors. Have learned a few things from that experience. Most important is that if you don't address drainage no amount of sand can help. Neighbor just cleared off an area and filled it with sand. The area they had the pen in held water a bit prior to the pen. Got much worse afterwards. Fortunately we have a site with better natural drainage. I'm still going to put in some perforated drainage pipe with a fabric sleeve on it around the perimeter to help it dry faster.

Good luck with your project.

 

[Schneeky]

We've got the panels and a coupla gates ready for the round pen. Not gonna mess with those till we get the footing done, tho'. We set it up temporarily just to see if we liked the size and layout. Worked nicely. Are there any specifics to the "stone dust" or is that the "official" name for it a quarry would recognize? We have Vulcan in our AO.
I noticed the RR ties on the outside. She had talked about some planking fastened to the outer bottoms of the panels to contain the sand. Is one better than the other?

Egon- It pretty much had a natural slope to it already. The strange thing being that it went from orange "sandy" clay up near the pine tree to red sticky clay near the fence.

 

[Schneeky]

Most important is that if you don't address drainage no amount of sand can help.

That's what I'm fixin to work on before any footing goes in. I've prolly got enough fall to get a good bit of the water out. But will most likely end up with a little water in the bottom. Coupla inches or so. The wall of the pen at that location is ~8".
..Ya reckon it's no biggie if the water level is well below the top of all the aggregate?

As a side. I had no idea how much dirt would come out of this hole. Needless to say I'm all set for fill and topsoil for a good bit.

 

[ROUSTABOUT]

Drag the low side out so it won't hold water like a mud hole. I work with big names in rodeo. Put some kind of Sandy loose something on top of the clay.

 

[ponytug]

We had something similar and it turned to 18" of mushy clay every wet season.

Definitely make sure that the land around the arena isn't draining into it. BTDT. It makes your issues worse. My advice is try to end up six inches to a foot above grade.

I think that non-equestrians underestimate how hard horse are on round pens. I couldn't put in six inches of coarse gravel, but if you can, I would recommend at least six inches, well compacted, and then put down geotextile and then sand or pea gravel, 4-6" deep, but don't use building sand. You want washed sand. Contrary to lore, geotextiles will fill with silt and sediment and clog, it is just a question of how long. Clay and silt are their worst enemies.

I put in French drains in pea gravel because I had 15'+ of clay and I wanted a solid footing. Then geotextile and six inches of pea gravel. It has been thirteen years and it has worked well, though I can see the difference in how fast water moves through the geotextile between the first year and this year.

All the best,

Peter

 

[Schneeky]

Thanks much for the replies, fellas. We're takin it all in. Don't wanna rush this thing and jack it up.
Here's a coupla more pics of the area from the county GIS site. I tried a quick area measurement tool to mark the location of the round pen. The "top" of the pen is near the lone pine. It appears that's a high point and we may have somethin like 2' of fall from the top to bottom.

If I cut a drainage down at the "bottom" would that let whatever aggregate I used out as well?
Is there a trick to it? Thanks..