Better drainage

USAFpj · Jun 4, 2019

Guys, the house has been built for almost 4 years now, and I need to wrangle the drainage issue. As you can see if you look at the far side trees, our home sits on a hillside- 8inches in the rear, and 12feet in the front.

So water comes off of the hill to the left of the picture, and drains poorly due to a sandy/heavily red clay combo. To mitigate the pond that eventually builds, is there an easier way to control the water run-off? For now, I'm thinking to turn the downspout 90 degrees and connect it directly into a 4in PVC pipe that would then run alongside a French Drain to control the uphill water?

Another option is no pipes, but make a 24in x 24in ditch and just fill it with crusher run, and it would then naturally drain out at the far end of the image?

Looking for any options to control this water, but not make an engineering project out of it?

EddieWalker · Jun 4, 2019

French drains sound like a great idea, but in my experience, they always end up clogging up and failing. It's just a matter of when and how long it works for you. The only 100% sure fix for this is to start removing dirt to create a ditch. Make it as wide as possible so it's not ugly and you can mow it. Nothing else will work long term.

USAFpj · Jun 4, 2019

Eddie- maybe if I concentrated on building grass back there instead of the current sand/clay, the water would slow and perhaps absorb a bit vs. collecting and standing..

CobyRupert · Jun 4, 2019

This looks very similar to where my barn is located with similar issues. Except my upper side also has "springs" in it, in addition to runoff, in addition to footing drain for uphill house spilling out uphill of barn. Even worse, barn is pole barn so wood columns are susceptible to being in water. Also snow would come off the roof, pile up under the eves and then melt and find it's way to inside stone "floor" where there are spots lower than outside ground.

People give different opinions about French drains, about how well they work, how long they last, and problems with plugging/ soil infiltration. Maybe it comes down to soil types.
I was hesitant to put in rock or perforated pipes, have it fill with soil and be digging it out a few years later. Then there's the mesh...etc...

I finally had to wrap my head around the fact that the building is fixed. And interior floor is fixed. And it needs to be higher than everything around it. IT is the starting, ending, and base point. I ended up sloping everything down, starting at very edge of the building, to an open ditch/swail about 9 feet away from building where you have your French drain indicated.
I left it open because:
I'm cheap and didn't feel like getting stone delivered.
I will want to periodically adjust / clean out the ditch to maintain the slope away from building (especially when only dealing with a few inches difference, subject to filing in over time) and don't want to deal with stone or pipes in the way.

RoyKing · Jun 4, 2019

First of the gutter drains need extending away from the foundation, the water will eventually sag the foundation. Put those splash tray down. Next run off from up the hill, you need to cut some wide shallow swags up the hill at each of the house and pile the dirt in the middle. So as the water comes down the hill it runs around the house. Actually I would cut a U shaped swag up the hill with open end facing the house, to catch the water above and divert around house.

USAFpj · Jun 4, 2019

Roy, why don't you like a wider ditch where you see that sand?

The picture doesn't show it well, but that sandy spot is a swale. My block foundation and perimeter is higher than that low spot, and has never flooded. I just don't like that swale holding onto water as long as it does.

I feel I need to widen that swale, and increase the rate at which it drops to the far side of the picture, where it will drain. Where the picture was taken is my gravel drive and entrances to the home- definitely don't want to divert water in that direction.

Another project is to steal some topsoil from other parts of the acreage and spread it all over that backside and replant in fescue/rye...

RoyKing · Jun 4, 2019

The swale holds water from roof gutters and what rolls down the bank. So for a point of reference I'm standing with my back to the house looking up the hill. The two legs of the U shape ditch will come down to left and right of the house diverting water coming down the hill from above the ditch. The dirt from ditch will be put inside the U forcing that water to go left and right around the house. The gutter drains will extended left and right also. Therefore your swale highest point is in the middle forcing everything left or right. So the crest of the crown will at the center of the U so all water entering goes left and right and all water inside U legs goes left or right. And gutter next to the foundation will dissolve the calcium in the sand and clay in 20 25 years sag the foundation