So my arena went in this year, and now that we have hit the rainy season (and then some, after 3 months of dry, now we've had more rain in the last couple of weeks than we normally get in the whole month of October!). The base is crushed rock/screenings stuff and the footing is sand/rubber/fiber mix. I'm noticing that one area is staying wetter than anywhere else.
Arena slopes 1.5% from north to south (and is 165' long east to west, 80' north to south, so the slope is across the short direction). Yesterday after a few hours of dry, the whole west, south, and east sides are dried out great, yet there is still some wet squishiness on the north/central side, which should be the highest point?
I haven't gone to check yet today (too dark at feeding time in the morning!), but suspect that the whole thing will be okay now that we had a dry night. But does it seem "right" that there would be such a discrepancy in the drying like that?
I'm trying to decide if I need to have the arena guy out to check things. Maybe because it is so new, it will take time for everything to get saturated enough to really see what the drainage is like? I mean, we totally over engineered this thing with drains above and below and around and retaining walls and etc. I'm kind of bummed that it isn't drying out as fast and evenly as I thought it would. Maybe my expectations are too high??
Sounds normal to me - when I put in my ring it was done in October. A couple of weeks after it was done it rained and I had quicksand areas - like sink in nearly a foot into soup when *I* stepped in it, nevermind a horse. These areas were fine when it was dry.
I panicked and called the builder who told me that it really did need its 6 months of settling and if the issue still existed come spring he would fix it. Come spring I had no problems, and have not had one issue since.
It was more dumb luck than great planning that i had it built in the fall and it had all winter to settle but it really did make a difference. And it was professionally compacted.
I'd let the builder know, but my guess is he will tell you it needs time.
Our arena was completed in June - ours is a 1% crown and a 1% slope. 6" base of class I sand, laser leveled, compacted, swales, etc. - we spent the money to have it done correctly (ouch). 180' by 90' and sloped down the long way, crowned the short way. The footing is sand/rubber. So it should drain to the sides and down. Well, similar to what you are describing, the last area to drain after a prolonged and heavy rain was about 1/4 of the way down from the top of the slope - not what we would have expected. Could it be that the footing is a little deeper at the bottom of the slope (our rubber does travel a bit in heavy rain)? We were a bit perplexed by it, but the arena drained very quickly in general, so it's hard to get too concerned about it. We also would have expected the pooled area to be on the rail, at the bottom of the crowned slope, but it was more towards the middle. Since the footing does tend to get deep along the rail, maybe it simply absorbs more water.
Just curious - do you have any trouble with your rubber washing down the slope in very heavy rain? What do you use to keep your footing in?
Sorry I don't have an answer, but my experience is similar, so I hope it makes you feel better.
Both answers make me feel somewhat better, thanks. We did talk to the builder, who said something similar to what Hilary posted, that it would need time to settle and absorb water and everything we described sounded like it was working right. But I'm going to see what this weekend of rain does to it...we've already gotten our October quota in just 2 weeks, and looks like that may be doubled by Monday!
For now, we have RR ties on the west & east ends set directly on the base to hold the footing in. North side (highest) has a concrete retaining wall holding the slope above back, so footing won't ever escape there. Then on the south side, where the water should go as the slope is that direction, I've got a temporary border of wood with a gap beneath to allow the water to flow through. Eventually when we put up a permanent fence (right now, just have a temp one as I'm not sure how I want to fence), we will use 2x6 treated t&g boards, stacked 2 high, attached to the fence to hold the footing in. I haven't seen much loss yet, but it has only been a month and the rains are just getting going!
Windward Farm, Washougal, WA- our work in progress, our money pit, our home!
Just a thought-you might have a small spring in that area. At my old house, we had seasonal springs that would crop up on hillsides during periods of heavy, prolonged rain. They often ran for days after the rain let up. Or it could be as the above posters said-just throwing that out there.
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