Working around septic system

dliston · Jul 30, 2004

Didn't know what forum to post this - seems as good a place as any.

I'm a new user - got a fair sized tractor - NH TC40DA with R4 tires - do I need to worry about driving it over my leach lines or septic tank? Have some work to do near the house and really don't want to watch my baby sink slowly into a very foul smelling hole.

Thanks,

chim · Jul 30, 2004

( Have some work to do near the house and really don't want to watch my baby sink slowly into a very foul smelling hole.)

I drive over mine with a B7500 every time I mow. I'd avoid having a concrete truck cross it, but have never worried about the tractor. If the ground is mushy enough to sink a tractor, you already have problems...................chim

Yankee · Jul 30, 2004

The contractor used a lot bigger tractor than mine to backfill the box and drain field, probably as large as your TC40. It was dry at that point, however. I don't worry about running my B7610 over it. My neighbor just had some landscaping done. The contractor used a pretty good-sized tractor to prepare a seed bed over his system. No problem at all.

Keith_TN65 · Jul 30, 2004

I've always heard to keep your mowing machine under 3000 pounds when mowing over the septic system. More to keep from compacting the ground around the leech bed than anything else. I imagine moving a heavier machine over the lines once and a while would not be too bad.

ByronBob · Jul 30, 2004

Just built a new house. Excavator drove a bulldozer over my leach field. It appears he also drove over the tank but not the distribution box. Physics told me that was probably a good idea.

Even if your tractor is 3000 pounds it's distributed over your tires so the load really becomes much less. If you can position the tractor so some of it is out of harms way then thats all the better. Your judgement and common sense should be fine.

My D-Box crumbled after 30 years of use. I never drove over it so you gotta think age did it. The materials they build tanks with now are far better. They have fiber reinforced materials in concrete and such to help it cure and have stronger bonding characteristics.

DiskDoctr · Jul 30, 2004

Doug,

Avoid the lid for sure. This is a weak point and I've seen tank and cesspools collapse. Probably due to wedge shaped lids that wear or tilt.

Once they push through, it's much more likely to collapse the flat top.

Good news is most lids have a metal loop in it, so a metal detector finds it quite easily.

Also- avoid a lot of heavy traffic over your leach field. This is the set of pipes and gravel beds (depending upon type of system) that extend from the tank. If you compact this soil too tightly, you can have drainage problems.

This are is sometimes softer or a bit mushy, depending upon the health of your system.

Not sure if your NH is big enough to be a problem, maybe someone else can help there. Just thought some background would be helpful.

-JC

nobull1 · Jul 30, 2004

Well I will disagree with most of the replies so far /forums/images/graemlins/blush.gif.I use my KX 91-3 7500lb excavator or similar and L4300 5200lb on a lot of customer yards.I have seen what can happen when people use this type of equipment on or around septic systems, not good.A lot of times if the ground is dry it doesn't appear to be a problem.The long term effect of driving over the system can be compaction as was mentioned,crushed pipe,blocked pipe etc.A lot of the times you will not even know you have a problem till days,months or even years go by.When a customer wants me to go over his field I just about want his first born in my hands so he wont try and blame me if he has problems later.Now after all that being said, I go over fields all the time but only if I have to and never for convienience.Also I try to never drive over the tank or 5' from each side as I have seen the pipe coming/going from the tank become broken pulled out etc.The weight of the machine on the tank if it doesn't crush a weak top can possibly move the tank and cause the above problems.As you can tell I don't like driving near septic systems.The grief that a broken system causes is bad news.Wait till the wife flushes and it doesn't go away or "honey it came back all over the floor" /forums/images/graemlins/blush.gif.Cost of repairing these systems is a lot and you have to be certified in our area to even work on them.If on your own property you have to drive over the system at least lay down some boards or something to distribute the weight it will help but not the answer.

LarryD · Jul 30, 2004

The line from my tank to the drain field cuts through a large part of my property and I drive over it frequently without any problems, it actually runs under my driveway at one point. I do have a little raised flower bed over tank and only drive through the drainfield when absolutely necessary (avoid the ground compaction). I think you should be fine doing some minor tractoring but do keep an eye out for any soft spots or water migrating to the surface.

viking · Jul 30, 2004

In March I had my line replaced from the house to the septic tank. The septic guy that dug up the line said it was no problem to drive his JD 5400 TLB over the tank. Well, in May one of the slats that cover my tank collapsed into the tank. My tank is old school and has three 3'x4' concrete slats that act as a lid to cover the tank. I had a new lid made and set it myself. I specifically asked him if driving over the tank was okay and ofcourse he thought it was. Ironically, when I ordered my concrete slab at a local septic company they asked if I had driven anything over the tank lately.
Now, could the tank have settled on it's own over that last 40 years prior and caused a crack? Yes, it could have, but.....
Needless to say, I would never drive over a septic tank.

Junkman · Jul 30, 2004

It depends on how far down your tank is. My tank is 15' from the top cover to the top of the ground. I have a concrete man hole to access the clean out for pumping. You could drive a tank over it and not damage it. It all depends on the type of tank, how far down, what the tank is sitting on for a base, etc. There are no hard and fast rules to this question, but just more questions than answers before you will find the correct answer. As for the leach field, stay off of it at all costs. You don't want compaction of the leach field. I would mow the grass above the leach field with a very small mower or tractor. As for the distribution box, they are usually quite close to the surface of the ground, and I would also be leery of driving over it with a heavy tractor. Time of the year and soil condition are another issue to be considered. If the ground is "mushy", stay off of the tank, lines, etc. Know where everything is located and you can devise a plan that will allow you to parallel the lines and not drive over them, but place the tractor center over them, with the wheels straddling the sides if neccessary...

Poncho · Jul 31, 2004

My septic is right by my house and is only about a foot down, and fortunately I mow over it with a garden tractor. My drain/leech field is about 125-150 from my house (connected by PVC pipeabout 20-24" down. The installer said no problem driving over the PVC pipe and now problem driving over the leech field with my MF135 to bush hog the bahia grass. Also no problem to allow horses to graze over the drain/leech field. The leech field is about 30 inches down and I have a sandy loam soil .... which means drainage is not a problem. I would be leary about driving over a septic tank with a nominal size tractor unless it's as deep as what Junkman's is.

DiskDoctr · Jul 31, 2004

Junkman,

15 feet down? Wow... around here, we call that a coal mine /forums/images/graemlins/grin.gif We're lucky to have local tanks 18-30 inches down.

-JC

Junkman · Jul 31, 2004

When I built my home, I wanted a 10' deep cellar and for the septic line to go under the cellar floor. They got down about 5' and hit hard pan that wouldn't budge. Told me that the septic would never make it under the cellar floor. I said, that we will try when the time came to dig the hole. They hit a vein of pure sandy gravel and had no problem digging the hole for the tank. At that time, it was only 10' to the top of the ground. We have since landscaped and removed a lot of material from the side of the house and put it in the rear to create a backyard. Before it was a sharp drop off from the house. The only time that it is a problem is when the tank is pumped. The can't get to the side edges with the shovel. If the baffle ever breaks off, I am in a lot of trouble. I have the tank pumped every 3 years and have never had a problem.

TommyP · Jul 31, 2004

I would like to throw out another question. I have a mound type septic system. I have a JD 2210 and I am a little leery about driving over it to mow. I use a push mower to get after it but the darn thing quit working. Do you think I can safely drive over the mound without damaging the drainfield?

frank_f15 · Jul 31, 2004

A lot depends on how far down the tank and leach fied is? i drive over mine all the time with my b2400, but i won't alow anything heavier than that.

JDgreen227 · Jul 31, 2004

My septic tank is less than a foot below the ground and although it's only twelve years old, I would not use my 3000 lb. JD to mow over it, as others have mentioned, the cover is the weak spot. As I don't know who installed the system, I am leery about driving over any part of it, I have marked the corners of the drainfield and tank and use a push mower to trim around and over them.

When we were having an excavation contractor here to dig our addition basement two years ago, I had clearly marked the entire septic system with stakes and caution tape, and several signs. The best marked item was the main line from house to septic tank, as it was the closest to the area being excavated.

The second best marked item was the water line from the well to the house.

The third best marked item was the 230 volt electrical line from the house to the well.

Here's a quiz for the TBN members: What did the guy running the excavator hit first?

What did he hit second?

After he hit the main sewer line, and then the water line, I got pissed off and insisted they start hand digging near the electrical line...and of course, one of them cut it with his shovel. I told the foreman, you got three strikes here today, one more and you are OUT of this project.

/forums/images/graemlins/frown.gif /forums/images/graemlins/blush.gif /forums/images/graemlins/confused.gif

DiskDoctr · Jul 31, 2004

( hand digging near the electrical line...and of course, one of them cut it with his shovel. )

Shocking how careless some can be /forums/images/graemlins/grin.gif

I hope you made them repair and get a little off their charge for the inconveniences...

-JC

Bobm · Aug 1, 2004

Just another opinion... my septic tank is down about 24". As I must drive over it (and lid!) with my B7200, I installed a 18" long, 30" diameter aluminum culvert in a vertical position over the septic tank cover. I made a wood (CCA treated) cover for the tank lid extenstion.

That way, literally no pressure can be exerted onto the lid, and getting at the lid is relatively easy as I only have to remove about 6" of soil.

The setup has been in existence for about 15 years, and yep, I've been B7200 mowing over my tank/leach field on clay soils for the past 20 years. Still - the clear lesson to be learned from this thread is "common sense prevails"... don't go over these things unless you must, then disperse weight as much as possible. Percolation is a bizarre animal. Capillary action is contingent upon soil type, pore size and a zillion other things.

Junkman · Aug 1, 2004

I wouldn't hazard a guess if it is safe to drive over. Too many variables. If I were building a new home, I would specify the standard for the tank to be of the type that can be driven over by trucks. The cost isn't in the tank, but the installation and repair if one fails. Don't remember the term that was used, but when a tank was installed in the parking lot near my store, it was of a grade of material that will withstand the weight of a tractor trailer. It has been in for over 10 years now and no truck has ever fallen into the tank. Most home tanks are quite thin and they can't withstand much weight.

stephan · Aug 2, 2004

When I was having a load of problems with smells in the house I did a lot of research (net) on septic and the do's and don'ts. Turns out a rubber seal had perished on the toilet causing the smell but here is what I learned about the leech field.
1. Don't drive on it. Period.
2. Don't plant anything but grass.
3. Don't let animals graze on it. Period.
4. Mow by hand and dispose of the cutting thoughtfully, not for animals.
5. If its very wet and smelly seek advice.
Now a lot of that has to do with compaction but some is to do with the little nasties that hang out around sewerage. I used to drive over mine with a RC and 40hp tractor (1800kg) but I have now fenced it off from man and beast.
I just reckon I have enough land that I don't need that bit and in the long run (as other people here have said) it costs more to fix so why take any risk?
I will add some links when I get around to it.