How Do Underground Septic Tanks Work?

[scorecard]

I have no real knowledge on this subject, here's my point / question:

The plastic underground septic tank typically installed at each house in new housing developments, say about 2metres in height:

- Does the water from the shower, washing machine, kitchen sink, flushing toilets, etc.,, all go into this tank?

- Is it kept separated in any way?

- Does human waste from toilets go into the same septic tank? Is it kept separate from shower, washing machine waste?

- If there are 3 three adults and two children all showering say twice a day, washing machine water for laundry for same group, toilet flushing etc., surely this is large amount of water, so how does the septic tank 'deal' with all this water without the tank overflowing?

Please share, thanks.

[wana]

im not sure if its the same in thailand but in some countries you have a tank for your toilet waste only and someone comes every 2-3 months and sucks it up with a vacuum cleaner on his truck and deliveres it to the waste treatment plant for recycling

you pay some fee for this service normaly

[PattayaParent]

GIYF

[Rimmer]

I'll move this to the DIY forum, they know about all this kind of stuff over there.

[Eric1949]

It's only toilet waste that goes into the septic tank. It then bio degrades and comes out as 'clean' water. Mine then goes into a soak away, and is never seen again. I do not have a truck coming to suck out the waste. So far it's worked for 7 years. All other water waste from the house by passes the septic tank and meets up with the pipes after the septic tank exit.

[dean999]

Hope this helps.

Here is another good link. http://home.howstuffworks.com/home-improvement/plumbing/sewer2.htm Edited March 9, 2012 by dean999

[loong]

im not sure if its the same in thailand but in some countries you have a tank for your toilet waste only and someone comes every 2-3 months and sucks it up with a vacuum cleaner on his truck and deliveres it to the waste treatment plant for recycling

you pay some fee for this service normaly

I think that you are referring to a cess pit here. In Septic tanks bacteria that work in the absence of oxygen will remove most toxins and relatively clean water will flow out. Depending on the size of the septic tank, how many people in the household and how many curries they eat, solids do build up and it will need to be emptied maybe every 3 to 5 years

[Kwasaki]

It's best to have a twin septic tank design installed although one can be enough depending on usage and population use, water income to showers and house supply come from wells or government supply. What are you worried about.

[craigt3365]

Our tank is as you described. The shower, sink and toilet flow into it. The kitchen goes into a drain that goes around the house, as does the washer. Given the amount of water going into our tank (it serves 2 bathrooms) I'm assuming most just overflows into the same drain around the house and then out into the main storm drain.

[Langsuan Man]

Diagram of a typical Thai septic system:

[craigt3365]

Diagram of a typical Thai septic system:

That's what we have! Only the outflow goes right into the street drains. Doubt that's much different from many other villages?