How to be sure of septic field location

[Pokeberry Mary]

We have a map of our land and it says the septic field is in one spot, but the guy who recently pumped the septic says it is probably going a different direction--which would put it right smack under the area I am using for garden.

Is there some way to tell for sure where it is? There are very few spots in our yard where I can garden due to hills full of trees. I laid out an area on a sunny hill and have been working on getting it terraced and building up soil. I've already gotten one season's gardening done there and am in the middle of planting my fall crops-- no I'm wondering if I need to relocate the whole thing.
:girl_cray3:

[Pokeberry Mary]

I probably put this post in the wrong area. My bad.. hope someone stumbles across it anyhow. :o

[Anon001]

I probably put this post in the wrong area. My bad.. hope someone stumbles across it anyhow. :o

LOL I think I might have put in under garden. lol It depends on the type of septic system you have as to whether you would want a garden above it. Frankly, I wouldn't be afraid to grow above ground crops over it. But, I wold hesitate with potatoes, carrots, radishes, etc. Since I live alone, I certainly wouldn't worry about the above ground....

Did he say why he thought the septic went in a different direction?

[Catalpa]

Mary, if you have lots of hills and trees, you can bet that your septic field is in the one sunny flat spot!

Here's a few thoughts:

In my experience, the pumper truck guys are really good at driving pumper trucks and running the pump. They aren't usually as knowledgeable about the actual septic system as they claim to be.

Is there one section of your yard where the grass grows better than anywhere else? Especially in long, narrow strips, or a square? Is there an area that gets mushy in the spring or after heavy rains? These are clues to the drainfield location.

The map that you say you have, was it drawn by the previous owners? Or is it a copy of the final approval on the system from the health department? How old is your place? Sometimes homeowners really have no clue about the system, or where it is....unless they put it in themselves (with or without a permit). If your place is old, chances are the info from the previous owner will be the more accurate, or if the place is newer, the local health department might have the better records. They're supposed to take measurements and draw a site plan as part of the inspection. You can check with them to see what records for your place are on file. You might want to query them for the well and septic records, anyways, it's always better to know what the government has in your records, and also that way YOU have the information, and can make informed decisions when taking care of your place.

Unless you have an accurate map, the only way to really know where the septic might be is to dig. If your soil isn't hard clay, you can use a probe rod to follow the pipe. The pipe will feel and sound differently than rocks or tree roots, but when in doubt, you'll have to dig.

Start at the outlet end of the septic tank, (the end further away from the house) and probe down until you find the outlet pipe. They're usually about 16" below the top of the tank. Most often it will go out the end of the tank (the shorter dimension) but sometimes it will run out of either side (the longer dimension). You can follow this pipe on it's way to the drainfield - it shouldn't take to long to find out which way it's headed, and that should let you know if the pumper guy or your map is right.

Gardening on top of your drainfield isn't the greatest idea.....if you have deep-rooted crops and not much soil cover, your plants could be taking up untreated sewage effluent, which can result in E. coli actually being IN the plant. It won't come off with washing. The use of sewage effluent as irrigation water has resulted in E. coli poisonings when people have eaten the vegetables. Secondly, a drainfield needs to breathe to operate effectively. If you place loads of topsoil, mulch, terracing, and such over the drainfield, you will cut off the air supply, and compact the absorption area below, leading to premature failure of the field. Use of a tiller or other garden implement could also damage the field....I've seen people actually hook a tiller tine on the drainpipe and pull it right out of the ground.

If all of this has confused you, please feel free to ask more questions!

Cat

[Quietgentleman]

I would take what is called a tile probe which is a rod about 4 or 5 foot long with a t handle at the end and sharpened to a point on the other. I would then go to where your map says the leach field is and start probing every 3 or 4 inches apart going cross ways to what the map says the legs are running. You should hit the rock of infiltrator just a foot of 2 under the ground. If you hit either on probe around to make sure its the field and not so stray rock or something. If its a modern system it will be either a rock system or a infiltrator system. The bottom of each leg shouldn't be much more than 30 inches deep. A rock system is a perforated pipe that is buried in a bed of 2 to 4 inch rock. A infiltrator is a plastic dome set in the ditch and buried. Either system is pretty easy to locate with a tile probe. Depending on the size of your house will determine how big the field is but the normal is 3 runs of about 100 feet each. They usually run along side each other few feet apart. Around here most rock system are dug in with a 30 inch bucket so the rock field should be about 30 inches wide. I never measure a infiltrator so I'm not sure how wide they are but I would guess 18 to 24 inches should cover that.

QGM

[backlash]

When I sold my house the County required my to have the septic tank pumped and inspected.
Since the County didn't do their job and they didn't record a drain field map I had to have the entire septic system mapped and recorded.
The guy that pumped the tank did the mapping.
He used some sort of electronic device and charged ME $350. :mad:
Plus another $300 to pump and inspect.
If the county had not lost the original map I wouldn't be out the $350 extra.
After all that NOBODY ever verified I had it done. Stupid County.
So I guess the answer to your question is it can be done but it cost a lot.
I have witched a drain field when it was plugged up.
Might be worth a shot.
If you do like quietgentelman suggests I would probe the area that the septic guy thinks it is.
You may have an old abandon drain filed and a newer one that is active.

backlash

[Pokeberry Mary]

It turns out we had two maps and the original one was for the permit for the septic system--the other was drawn in by the former owner. The place isn't old--we are actually not all finished building it yet--but the former owner had a knack for not being real 'accurate' in things he told us.

So yup-- I did start my garden over the leach bed and yup the pumper guy was right. The green grassy mushy spot-- yup--that's in the strawberry bed.

Well I'm glad I figured this out before I put any more beds in.

Time to move the garden. :meeting:

[Blacksmith]

but I'll make a post. I made a mistake about 20 years ago roto-tilling on my leach field....the system failed two years later because of the constant watering...from above...and below. never till a leach field!

Now..for placement of a leach field.

Your county has a USGS (Us Geological Survey) map of your exact location...which includes soil type...and topography. this document is free, and will give insight to the best location of a leach field.

[randallhilton]

Here's a link that mentions it:
http://www.unce.unr.edu/publications/files/ho/2007/fs0732.pdf

You've had some good advice already -- I would just add that you should know your system. If the leach field gets mushy then I wouldn't garden in it. It's not good for the plants nor the farmer. I sure wouldn't eat strawberries off the mushy ground!

If you have a mushy spot on a fairly new field then I think you already have a bigger problem than moving the beds.

[RobJob]

septic system would hopefully drain downgrade/below grade. Roots are the main enemy of the drain lines. Properly installed and deep enough to allow some "traffic/activity" over the lines might allow at least some raised beds. Over the actual septic tank not so good. When the system fails its generally going to backup out of the tank. And, you need to be able to get the access lid off to clean it.

I would think a little moisture in the root zone of the plants would not be excessive to cause extra problems with the functioning of the drain lines

[Catalpa]

Put the absorption field that deep and the system can't breathe and it'll sludge up faster. Backup won't come out of the tank until the pressure has really built up...it will back up in the house or fail out of the absorption field first.

Planting edible garden plants of any kind over the absortion field is not a good idea. If the field is too deep for the roots to reach, tilling and watering the garden will still adversely affect the field. If the field is shallow, not only will tilling and watering kill it, but the pathogens the roots will pick up could kill the gardener.

Think of it this way - imagine your yard after a three or four day heavy rain. Now remember that it's raining in your absorption field EVERY DAY. It needs to be left alone, without any additional water load placed on it.

[wtxgypsy]

As a legal installer in Texas, I would suggest that you only grow grass over the drainfield. Watering veges over the system will help cause waterlogging of the system and cause premature replacement of the drainfield.

It is best to not drive anything heavy over the drainfield (more than a mower). Heavy traffic will compact the ground and not let air evarporate the water.

I do know of one individuial who, after being warned, built a drive over the poly (heavy plastic) septic tank and a circle drive over the drainfield. This system is over 4 years old with no problems. Two retired folks live there.

The state inspector has verified this, but the system was installed to state specs. She can not believe that that they did this and it still works.

For everyones information, I will include the following:

The State of Texas requires one-third less total drainfield using enviromental chambers instead of a pipe and gravel system. Chambers are varied in sizes, but standard is approx. 3 ft wide and 4 - 6 ft long. The excevated dirt is used to backfill these chambers. Have had some installed over 10 years with no problems.

Aerobics systems (for those who dont have to deal with them) are mini sewer treatment systems. They include a septic tank (trash tank), clairfier ( aerobic unit) and pump tank. There is an air compressor constantly pumping air into the clairfier. After a leval is reached or a timer sets off, the water is pumped thru sprinklers or an underground drip system. If sprinklers are used, the effulent has to be disenficted, either chlorine or uv light. You do not want spray water to contact any food product (veges or trees). The downfall of these systems are the air pump and water pump.

Trees should not be planted over drainlines, but we installed one of our systems in 1982. It was over-installed at the then current specs. There are trees over each leg of the drainfield. 4 folks showering, laundering, and a dishwasher were invoulved. The tank has never been pumped. not recomended, but still working.

If there is any interest in more of this, I could be perswaded to write up each type of system.