Septic System Backup

Hi All,

I've recently had a septic backup into my basement utility room, of which the water was clear and had no smell, soap bubbles, or anything. The water had come up slowly through the cleanout which is level with the basement floor, as well as the air conditioning condensate drain, and a nearby floor drain. When checking the water level in the floor-level cleanout about 2 hours later, the level was almost to the bottom of the cleanout. The amount of water was enough to cause the surrounding room's carpet to be soggy, but no standing water. We have 3 large dehumidifiers as well as 6 blower fans going to dry the area out.

The toilet flushes fine, and all other fixtures are draining properly. The septic tank was last pumped out a 1-1/2 years ago, and it's only my wife and I at our house. Maybe it's time for a cleaning? I thought 2-3 years was typical?

The weather has been in a freeze / thaw mode lately, and the leach field area is not soggy. We've had heavy rains in the fall and had no problems with a backup. I opened up the inspection cover for the inlet section and the level seems to be about 6" down from the top of the inlet container. I can't see the inlet pipe to determine where the water level falls in regards to the inlet.

The shower was used this morning for about 10 minutes, as well as the toilet and bathroom sink. There was very little if any water in the cleanout after checking an hour later.

The only other problem was that a ground hog had dug a hole near the house and may have damaged the foundation drain tile. I don't know if this is a coincidence, or somehow the foundation drain and the septic system are connected in some way.

My house was built in 1977, although the septic system was installed in 1990 (Jet Aerator system) and has been serviced regularly by the previous owners (documents in hand). The house is on the side of a hill with a steep grade, so I would be surprised if it was water from the foundation drain coming through the sanitary line.

Sorry for the long post, just wanted to be thorough. Any advice is greatly appreciated.

benbecker said:

...the water was clear and had no smell, soap bubbles, or anything...

Click to expand...

It is not the septic then and you are barking up the wrong tree. It sounds like ground water.

That was my thinking, and I have a company with a jet cleaner and video equipment coming tomorrow to clean / video the drain tiles. The question is how the water is coming up through the sanitary pipe, or if those drains are really connected to the foundation drain and I'm confusing them for being connected to the septic system. Or the other case which is the septic piping has a break allowing water to fill up through that channel.

How common is it for houses of this age to have foundation drains connected to septic systems?

When they video the drain tiles tomorrow, they will confirm whether or not it is tied to the septic, which I really doubt it is.

I was able to confirm that the cleanout is in fact tied to the floor drain and condensate drain, as well as the main soil stack. I'll keep this thread updated when I find out the results from the drain tile.

If the drain tile isn't connected, the only other options are:

-The septic system has a leak and ground water has found it's way into the sanitary line and made its way up to basement level (unlikely, I have at least 15 feet of fall over a 40 foot run). It would more than likely instead drain to the septic system
-The leach field (in my case upflow filter bed) has been saturated / plugged and is drastically slowing draining, causing the "clean" water to backup at the cleanout and drains, which are the lowest points in my house before running to the septic system. The system was serviced 1-1/2 years ago
-The main septic line or septic inlet/outlet is or was plugged causing the backup.

If I missed something please let me know.

1. Do you have a sump pit or other pit with a pump?

2. Where do you think the foundation drain tiles put the water that is collected? I guess you think there is a pipe discharging down the hill. Good theory. Yet wouldn't you have noticed that pipe? It could be a french drain, in which case you would not have noticed. In dry periods you might be able to notice an effect on vegetation.

3. What happens to the washing machine water?

They sell dye that can be used to see if water makes it to a pit. It might help locate the downhill output pipe if there is one. I used such dye to see where some water was going, and it worked for me.