How do you eliminate leach line valleys?

[hufhouse]

Our house is about 3 years old, and we have a septic system with 1200 feet of leech line (12 lines 100 feet long). I can stand in my dining room and see all twelve leech lines because they have settled to about 2" lower than the surrounding lawn. And, since they are lower and moist, they tend to stay greener in the heat of summer, which really looks tacky. The depressions are about 6" wide. They also cause a problem because my lawn gets a little scalped when my deck rollers drop into these depressions. In other words, I have twelve depressions in my lawn 2" deep, 6" wide and 100 feet long. If I just go out and get some screened topsoil and rake it into each line, I'll have about 2" of topsoil with the grass underneath sticking out. I don't know if that will allow new grass to grow correctly, because there won't be a good soil base. The old grass will probably just die. Do I have to go to the time, trouble and hard work of taking up all the sod over each leech line and filling it in? What a hassle! Has anyone corrected a problem like this??

[arjr111]

Hi Guy, I did/do have this problem at my summer place, and I have been adding topsoil. It seems to be correcting the problem. Looks ugly, for a while, but a little seed and the grass comes up ok.

[hufhouse]

Art, When you did this at your summer place, did you put the topsoil in level with the surrounding area and just plant seed? I was thinking about doing this in stages...laying down about an inch of soil and raking it so that the underlying grass can see enough light to establish new turf, then repeating the process until everything is level. Then, I wouldn't even need to seed, although I probably would throw a little on just to help it fill in. Would that work better? Guy

[Tuffy]

You need fill.

[arjr111]

quote:

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Art, When you did this at your summer place, did you put the topsoil in level with the surrounding area and just plant seed? I was thinking about doing this in stages...laying down about an inch of soil and raking it so that the underlying grass can see enough light to establish new turf, then repeating the process until everything is level. Then, I wouldn't even need to seed, although I probably would throw a little on just to help it fill in. Would that work better?

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Hi Guy, I actually mounded slightly higher and let it settle back down. But, I wasn't really worried about how it looked cause the grass grows really full and fast in that particular area of the property.

[Brent_Baumer]

1200' of leach line? I think they allow 3' wide for calculation, that'd be 3600 sq ft of leach field. That would be a big system around here, dosing tank (second tank with a pump in it). You must have solid clay or a lot of bedrooms going into that septic system calculation. I don't have depressions but the grass is greener over my leach field. When it gets dry in the late summer, I too can see each line. Annoying but don't know what to do short of watering the heck out of the whole area which I'm not going to do. Brent

[thedaddycat]

I don't have a problem with the lines, but the area over the tank always seems to die out in the summer. Last year when I had it pumped I took all the soil out and covered it with the good humus rich soil from the garden, hoping it would retain water better than the sandy soil that was there. We'll see how it does this summer.....

[ReedS]

As to your leach field probleems I;d have to agree with the experts:D that you need to add top soil to those depressions. Kirk I had the same problem over my septic tank, the problem is that there is only about a foot or so of soil over my tank and it dries out when there is little rain. With any luck your humus will do better than the sand. Most of the time the grass grows better over the tank until it gets hot and dry unfortunately due the grade where my tank is I can't really add to the soil depth at least there is a tank!:D:p

[iweld]

I have 600' of leach lines in my yard. Haven't had any sinking but, it is ALWAYS greener over the lines. You can even up the soil all you want, but the grass lines will still be there. The only ways I can think to get rid of the green lines is to increase the distance from the grass to the tile to about 30 inches. (boy would this be expensive!) The other way would be to lay a strip of plastic over the greener lines and then spread fertilizer over the rest so it can "catch up". This would be cheaper, but the neighbors might talk.

[iweld]

I have 600' of leach lines in my yard. Haven't had any sinking but, it is ALWAYS greener over the lines. You can even up the soil all you want, but the grass lines will still be there. The only ways I can think to get rid of the green lines is to increase the distance from the grass to the tile to about 30 inches. (boy would this be expensive!) The other way would be to lay a strip of plastic over the greener lines and then spread fertilizer over the rest so it can "catch up". This would be cheaper, but the neighbors might talk.

[MikeES]

Daddycat, you have the signs of a GOOD drain field. If things are moist and the first stages of dry weather the grass over the "near surface" drain field should be greener with the moisture and nutrients. But when things really get dry, a good working drain field should dry out, by both drainage and (more importantly) EVAPORATION. This will cause the area to brown out more than the rest of the lawn.

[ReedS]

Mike I think Kirk was refering to the area over his tank turning brown and drying out which is a little different than having the area over the leach lines drying out and turning brown. I have the same problem with mine and in my case it's due to the fact that there isn't enough soil over the tank to retain moisture to keep the grass green esp in late July/Aug. But I will agree with you that evaporation is important and that a leach field that stays green all of the time isn't functioning the way that it should and will probably need repair.

[hufhouse]

I knew I would need to add topsoil, I just wondered if it could go right on top of the existing turf, or if I would need to take up the exising grass, add soil and then re-seed. I don't mind the green too much, but it just makes the long skinny depressions in my lawn look even dumber!

[JOHNP]

Guy, move into Akron and you won't have that problem. L.O.L.

[hufhouse]

But then I would need to hire your security firm so I could feel as safe as I do out here in the sticks! (Nice to "talk to" another Simplicity guy from the area. You're actually pretty close to where I live!)

[Kent]

Guy, I suggest you add your topsoil in two stages, 3/4" to an 1" at a time, and let the grass grow through that layer. Then add the top layer, and let it do that again. Adding 2" at one time might kill the grass entirely... Also, the type of grass might determine how much soil you can add without damaging it. Bluegrass is pretty "tender" stuff, whereas fescue is tough to kill... Bottom line is that I'd do some experimentation rather than tackling it as one big project. You can order enough loam to do the whole thing, paying only one delivery charge, but take it slow and easy on spreading it over the grass... Also, water it good after you add the loam, so it settles down around the roots, letting as much grass as possible stick out of the ground. This is based on my experience in San Antonio, where it's common practice to put topsoil over your entire St Augustine/carpetgrass lawn... My 2 cents.

[hufhouse]

Thanks, Kent. That's kind of what I am leaning toward. When I have filled low spots before without taking out the sod, I've always had a perimeter where the old grass died and the new grass didn't have enough good dirt to take hold. It takes a year or so to grow back together. I read an article on the internet once about "top-dressing." I thought maybe I could do something similar to that in a series of steps until it is all built up again. Hmmm. I wonder if I could get an old drop-spreader and spread a layer of screened topsoil with it? That would be easier than shoveling and raking.