We have a 1000 gallon conventional septic system that was installed in October 1977 with 50 feet of 36” drainline , according to an old bill we found. I guess that means we must still have the original drain field that was installed when the house was build in 1948. The tank keeps overflowing into the yard. We have had it pumped and inspected by a septic company that discovered nothing wrong with the tank. The drain field seems completely dry. We have several Live Oak trees in the area of the tank and backyard. Upon the advice of the septic company we have been placing copper sulfate in the clean-out openings of the lateral leading away from the tank. In our town, conventional systems must now be replaced with an aerobic system. Short of replacing the system, can you think of anything else we could check? We have always been very conservative with water usage and keeping the tank pumped. Could there be a clog in the junction box? I don’t know much about septic systems, so I hope I have supplied enough understandable information. Thank you for any help you can offer.

 

Hi and welcome.

If the lines are dry, and the tank is full.
There is a clog somewhere. My guess would be the dis.box.
The line that come from the tank to the lines may also be stopped up.
You could try getting a septic guy to jet the lines out. Most pumper people can do this.
You may find that there is just a stopped up pipe.

 

I had the same problem you described. In my case it was caused by a large rock that was backfilled over the tank discharge line midway between the tank and the DB. Over the years the rock gradually crushed and blocked the line.

 

Is the dis. box the same thing I'm calling the junction box? Is there any easy way to locate it? Thanks for your response.

 

What is the DB? Sorry my ignorance is showing. Thanks

 

distribution box / junction box

 

The distribution box will be somewhere between the output end of the septic tank and the leach field. If you have a long metal rod you can stick in the ground you can use it as a probe to locate the distribution box. Start at the output end of the septic tank and probe to find the pipe coming out. It is usually in the center of the end of the tank. Keep probing following the drain line. You should hear a difference in the sound the probe makes when it hits the distribution box and the top of the box will be higher than the drain line so the probe will not go as deeply in the ground.

If the probe does not work I dig a hole at the output end of the septic tank so I can see the drain line and which way it is heading then I dig a series of holes in that direction until I find what I'm looking for. If you dig a hole and can't find the pipe then go back and work from the last hole that had the pipe. Down here in NC many systems are buried quite shallow so digging the test holes is pretty quick and easy but when they are buried deep nothing beats diesel power (track hoe, backhoe, hydraulic excavator) to do the hard work for you.

 

Do you think another possiblity is that the drainfield has failed due to age (62 yrs old) and it won't accept anymore water? I would think if that was the cause, the drainfield would be wet instead of bone dry. Thanks for your insight.

 

Failure is always a possibility with a field that old but if it's dry I would make certain the effluent is getting there before spending the money to repair/replace the leach field.

 

A 1,000 gallon septic tank is good for 3 or 4 people. But, its the size of the drain field that matters, when it comes to absorbing liquid. Often, a home has two separate drain fields,when one stops working, due to salt or matt growth, leaving it for a year or so, brings it back to life. As previous, follow the pipe to the junction box, dig round the box, see how many pipes leave the box. Look inside the box to see what happens to the liquid, if one side is blocked, use the other.