hi, this is my first time posting here. i've been trying to find a diy solution for this and have come across a lot of info on permaculture. i'm kind of new to this but fascinated.the problem is this, we just removed an above ground pool and deck that sat at the bottom of a hill that is wooded. a lot of water runs down this hill and used to run under the bottom of the pool and out the other side. you can actually hear it running like a stream at times. so now we have a huge flat circle of sand at the foot of this hill with the excavated area where the deck was around it. we have heavy clay soil, really heavy. after a lot of pinterest research i was thinking a swale would help but now i'm not sure since water does not drain into the soil very much. i dug a hole in this spot last night bigger than a five gallon bucket and poured in a bucket of water and two hours later it didn't go down at all. then it rained all night and now there are puddles in the sand, which is sitting on clay. maybe a dry stream bed? but exactly where to start and end and what's it leading to. of course i want to start a garden here but must take care of drainage first. then last night me and my husband were watching you tube videos on hugelkultur and we thought that would be an awesome way to make the raised beds we want to put around the circle area left by the pool. we also have a lot of cut up wood from trees that were taken down a few years ago. can we just dig a drainage ditch fill it with gravel cover it with branches and leaves and etc then do a hugelkultur bed right in front of that?
This seems like a pretty good place to build some small terraces with silt/humus traps to help build soil that will retain more moisture. Try searching Sepp Holzer+ terrace or something along those lines, it should turn up some useful information. Even a crater garden with a small pond in the bottom, like they built in MT this year could be worth looking into (search that here as well). There are a lot of solutions to this problem, the hard part is going to be finding the one that creates the most benefit (stacking functions, creating more edge, etc). Good luck and keep us posted, this is definitely a site with a huge amount of potential.
I would plant that whole area with morning glories. Make it a nice splash of color for this year. If you like how it looks, with only a small bit of effort it can keep coming back every year. If not, if you have other plans, you can pile more biomass on top of the morning glories and let the whole thing rot over the winter. Then next year make your more permanent planting.
Morning glories do very well covering up spots like these that have heavy clay under them. The picture looks like a spot I had in my front yard, and I had been trying other things, but the morning glory that I planted last year finally did the trick. It's one of the few things that will outcompete Johnson grass (which is what I didn't want). Johnson grass really doesn't like being strangled with morning glory vines.
The soil here will come roaring back just fine. If you have some wood, I would recommend putting it up against the slope to catch some of the water running down. A log placed above ground will have a lot of similar effect to a swale dug in ground, and it looks a lot easier for your setup.
If you're dreaming of a "keyhole garden" shape, the round area may be a good start if you design now before weed progression.
Welcome to Permies.
Where are you located?
(You can add this info to your profile, if you are willing - in any format you like. It helps others who may know your region to give more pertinent advice.)
If you're in the Western USA, with the typical arid summer weather, you may be looking at watering that garden through 2 or 3 months of every summer, no matter what annual rainfall you get. Think about making big storage capacity for that runoff water in a swale, pond, or hugel bed (dig down a foot or two, put logs in, then bury them with the dirt you removed, add more topsoil if needed, and mulch. If you have enough topsoil available e.g. upslope, you don't need to dig the logs in, you can just drop them on level and surround them in dirt). I like how my hugel beds are performing in our eastern-Washington arid climate, and they'd also give your plants a raised-bed boost above the flooding when it does happen. But a hugel bed that will hold enough moisture for 2 or 3 months would be huge.
If you're in the south-east, or Midwest, or New England, (which seems more likely from the glimpse of hardwood trees around your house), then your summers may be more muggy, with thunder-and-rainstorms every few weeks or even most days. In that case, you may not need to hoard moisture for as long, although 'climate weirdening' means it may still be a good idea to build in some extra storage capacity. A simpler solution like a log barrier to slow the water runoff might be fine. Or raised beds of any type. Hugels in this context, as described above, might eliminate the need to irrigate at all. A hugel 2 or 3 feet tall seems to hold water for a week or two; larger ones longer.
Regardless of your location, slowing the water and collecting any silt or value from it is likely to be a better idea than simple drainage. it's easy to move water downhill, but hard to get it back. If you do use a gravel French drain, consider having it dump into a buried tank, cistern, barrel, etc. so you can pump it back up for irrigation. You could even put that drain on the slope above, so that the water storage becomes a feature conveniently accessible from your garden level.
thank you everyone for all your replies! sorry i took so long to reply but i just figured out i didn't see a reply button cuz i wasn't logged in! duh!
i should have mentioned i am in pittsburgh, its very humid in the summer and we usually get lots of rain. i am thinking of hugelkultur mainly to improve the soil, its solid clay. and also that area needs filled in or raised . also i love making stuff out of junk most people get rid of. like leaves and grass clippings etc. what a waste! i started lasagnegardening years ago and it's worked great for me most of the time. i've always thought of rotting wood as a beautiful thing. i even turned a couple tree stumps into "flower pots" before i even came across hugelkultur. now i'm addicted. i've been frying my brain on hugelkultur info on here and pinterest and youtube videos etc. we worked hard the other day evening out the area, not digging a hole, it's already a hole. and we dragged a bunch of cut up trees and fallen wood and every stick i could get my hands on. my hubby has been bagging all the grass he cuts and piling it up for me. i even went down the street in my pt cruiser with a tarp in the back and a pitch fork and loaded up a bunch or grass some landscaper dumped there. i'm about to start stalking landscapers and tree guys for wood chips and more clippings etc. so this weekend we are gonna start throwing logs on the hugel! yay! all i need is a bunch of dirt. i'll keep you posted on the progress. thanks again!
My advice is to bust the clay by adding a lot of organic material.
For example, pile leaves on top of the site and let nature break it down and transport it into the soil. If you're impatient, then dig it in. You can't add too much either, so follow the Geoff Lawton rule of adding so much that you think it's ridiculous, double that amount and then add another 15%.