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Do I need a Dry Well?

I'm in the process of re-doing our side lawn, but before I can re-seed I need to fix a little drainage problem.

It might be difficult to see, but the puddle goes all the way back to the exterior tankless hot water heater. You might have noticed that even the river birch is having some trouble digging into the tough Georgia clay.

The source or the water is strictly rain run off. Our gutter dumps into the puddle (rain barrel is in the garage and waiting to be installed). The neighbor's house doesn't have any gutters on this side.

So how should I fix this. Is a dry well the way to go? Or is there another way?

If a dry well is the way to go, where can I get some info on installing one. I remember seeing Roger Cook install one on "Ask This Old House", but I can't seem to find any info on the website.

Thanks in advance.

Re: Do I need a Dry Well?

There are three basic ways to approach this---one is to build a drywell underground (basicly, a large hole filled with rocks, perforated steel drum, heavy duty perforated plastic trash barrel, stone, gravel, etc.---use whatever you have hanging around the house---but no wood)large enough to absorb enough of the runoff to slowly leech it into the ground (assuming it will be slow draining due to the clay present in the soil)---another is to establish a pitch toward the street (where the photos were taken??) & move the water by 4" drain or thin concrete/asphalt slab to the street, if it is permitted by city code (it usually is); a third is to bury a network of perforated 4" drainpipe just under the soil (amend the soil with gravel/sand for better drainage) & pitch it toward the street or another part of the yard that has better drainage.

Some sites for building a drywell are listed below---but explore all 3 options.

Google "soggy yard" drywell for more sites.

Sometimes if you dig down 3 to 4 feet, you may break thru the clay layer (you will notice a change in the soil composition as you dig deeper) so you get better drainage---if not, you will have to amend the soil because clay does not drain water very well, so sand, loam, pea stone, etc. must be added.

To save money, you can buy some hardware cloth (perforated metal webbing), nail it to a 2 X 4 square, place it over a wheelbarrow, & sift the clay to get the small stones out---the small stones are used for drainage in the drywell hole.

Another strategy is to do a "perc" test at different points by digging 1' holes & pouring water in---the hole with the best drainage is where you dig the drywell---"drywell" is essentially the same as "french drain".

All these methods rely on improving drainage by using pea stone, gravel, sand, or loam to mix with the clay---if your yard is solid clay with little or no drainage, opt for a system that uses gravity to drain the water to the street curb or a distant part of the yard that has less clay & has better drainage----buy a large, 4' torpedo spirit level or stretch a long nylon string with an attached line level from one side of your yard to another to establish a downward pitch to your soil so you can establish which way the water will flow away from the pooling water.

When done with the drywell, or drain lines, they can be covered with 2" of topsoil composed of 1/2 clay & the rest sand & loam---this mixture will support grass seed---the grassy soil will quicky drain the water down to the drywell & improve the appearance of the yard with a nice grass finish---another option is to finish with an attractive crushed stone that will also allow good drainage.


A. Spruce
Re: Do I need a Dry Well?

I would do two things. First, install line drainage to the street to divert downspout runoff to municipal storm systems. Second, I would regrade the soil so that it naturally sheds water away from the house and towards the street. If the neighbors property is draining into yours, that is the NEIGHBOR'S problem, not yours. Speak with the neighbor about him installing his own drainage system. If he won't deal with his runoff, then contact the municipal building authority and they should make him deal with it.

Re: Do I need a Dry Well?

Thanks for all the advice.

I'm a little stuck on this "regrade such that the run off pitches away from the house and toward the street." If I pitch the yard such that rain runs off toward the street, then that requires quite a bit of fill (especially in the back by the garage door). By itseslf that's not a problem, but doesn't that exacerbate the problem behind the white flexible downspout?

Also if I lay drainage pipes pitched toward the street where does the end of the pipe go? It's not pictured but I've got a curb. Am I allowed to chissel a chunck of my curb stone away so the pipe has an outlet?

I'm starting to think this is a bit bigger project than I'm prepared to handle on my own. In a situation like this, who should I call for direction? A landscape architect?

Re: Do I need a Dry Well?


Yes, it all sounds confusing at first, but there's usually no need to cut thru a curbstone---water flows by gravity, and the slightest pitch is enough to get it going in one direction.

The standard pitch used for good water flow is 1/8" per foot---this would mean that even over a 32' span of 4" drain pipe, the drop of the pipe from high end to low end discharge would be a mere 4".

The amount of "pitch" you have to work with from the back of your property to the curb can be quickly determined by using a thin nylon string with a line level attached, that is stretched over the distance involved.

I agree that a consultation is a good idea---consult the Yellow Pages under Landscape Contractors in your area to get several estimates---many of them do this kind of work.

Re: Do I need a Dry Well?

the Drywell Kit to dispose of storm water roof runoff, gutter, driveway, sump pump, sidewalk & yard drainage water and French drains away from your wet leaky basement. If you are serious about saving energy in your home, one of the most cost-effective fixes is to divert rainwater AWAY from your foundation to drywells (our $169 kit) installed in large gravel-filled holes in yard (leach pits). A dry foundation is a warm foundation.

Re: Do I need a Dry Well?

I don't think the drywell will give the results you wish do to the clay soil. Checking the grade and pitching the water may do best, possibly in combination with a french drain that could pull water from up between the houses.

Re: Do I need a Dry Well?

I agree with kcb --- if the ground is saturated then a drywell won't do much good.

Either sloping the ground to provide natural runoff or putting a 90 and extending the downspout further down may work .

Re: Do I need a Dry Well?

How about a rain barrel and repitching the area around there.

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