Septic tank info ?

[Majestic Creek]

I purchased my house new 6 years ago, initially as a holiday home, so usage was minimal. Maybe three weeks holiday, plus a few trips down here for a week or so.

My septic tank was never emptied, just used and seemed to drain away.

I retired last year and now live in Hua Hin permanently, just my GF and I in the house. But now I have to have the tanks emptied on a regular basis, about every six weeks, when the toilets are slow to flush and I can see the tanks are full. I get charged 600 bht per visit of the 'sludge gulper' lorry, which I think is good value for money! No complaints there, at about 100 bht per week.

But my GF's family live in a house in the town, there are 4 people living there, so the usage is twice ours, but they never have to have the tanks emptied ??? She says that the secondary tank that takes the over flow of water from the main tank has a pipe running into the drains, so the water just flows away. The effluent in the main tank is destroyed by enzymes.

I have a large black tank, filled with plastic 'cages' that fills up with the main effluent, then the water flows into a second tank which has a small screw top, about the size of a small plate. This seems to be the same at other houses I have checked here too.

Can any one explain why this differs to my GF's house and if it is right to have an overflow for the dirty water to empty into the main drainage system ?

[brianks]

Kind of obvious what the problem is. Your soak-a-way tank is not dissipating any of the water it is receiving. In other words its not draining! Takes a couple of weeks for your tanks to fill up and since none is draining out you have to pump it out. Need to get someone out there to look at the secondary soak-a-way tank and see why it is not draining its water into the surrounding ground. You should not have to pump your tank for years under normal usage if everything is working right.

[Takiap]

If you watch how these tanks are installed, I'm surprised more people aren't have to pump their tanks out. The overflow from the soak away tank should drain away into ground that is able to take it. Here in Thailand they just bury the tank and hope for the best rather than preparing the ground around the soak away.

You'll have to continue doing as you are, or else get someone it to sort of the ground around the overflow.

[Nereus]

and if it is right to have an overflow for the dirty water to empty into the main drainage system ?

Yes, it is not dirty water, but "grey" water. It should either drain into a long "leach drain", or the storm water drain.

[PeteC]

All the ones I've ever seen or had all drained into the storm drain. Pete

[Majestic Creek]

Thanks for the replies, which seem to point to bad initial installation! Not surprising really here in the LOS !

Both tanks are covered over with a big sand wash area, with just the manhole and drain covers showing, so cannot be removed without major excavation.

If there is no easy solution, will just have to continue with the sludge gulper lorry at 600 bht, which is still good value for money.

Another suggestion was to buy a cheap pump and suck out the grey water into the drain gully, but that seems a lot of messing about to save little money !

Any more advise very welcome, thanks.

[PeteC]

At minimum you should determine if your second tank is the type that drains into the ground, or into a storm drain trench. If the latter you should be able to see from the top hole why it's filing up and not draining into the trench. It may just be a matter of some kind of jam that a probe or snake can clear. If the former...indeed I guess it could be a bad drain field, perhaps nothing but hard packed clay beneath and little can be absorbed. Pete

[brianks]

I just remembered what we had at our first house in Hua Hin. A gray water tank had a submersible pump mounted at the bottom with a pipe leading up from it to outside the tank. The submersible pump had one of those float switches that when the water level got to the top it would turn the pump on and pump all the water out then shut off again. In our case it pumped out to the back of the house which was quite a smelly proposition. I rerouted it through the wall and the undeveloped plot behind. Now that the undeveloped plot behind might get developed everyone has been told to stop dumping the water there. All have had to now reroute the flow to the drain in the street. That should be something you could get done without digging up too much.

Can remember a neighbor who experienced the same situation as you and had to pump out his gray water tank every few weeks also. Turned out that the contractor never installed the submersible pump.

Check into it as it should solve your problem.

[Majestic Creek]

Thank you to all the contributors for help and advice. My curiosity got the better of me, so had a deep trench dug, about 1 metre deep, alongside the tank. Amazing !!! There was the over flow pipe exiting the tank, but the builder had left it to vent into the soil and had not bothered to take it into the drain which would have meant running it another few feet!
So the reason the system worked OK when I first bought the hose was the pipe let the water run out straight into the soil. But after a couple of years, it became a thick wet clay mess !! So no chance of water running away.
4000 bht later, have a trench dug to the drain, holes cut into the drain and a new bigger bore pipe fitted in replacement to the old 2 inch pipe fitted by the builder.
So I am sure this will cure the problem, as it was good to find a reason that the system had stopped working and now will wait and see if the tank level stays as it should.
Wait and see !

[MarlonPierce]

You need to have a new and bigger tank that has a capacity to store more waste. It might be possible that your current septic tank is small thus can easily get full. You may ask advice from septic pumping experts to provide long term solution to your issue.

[Nereus]

You need to have a new and bigger tank that has a capacity to store more waste. It might be possible that your current septic tank is small thus can easily get full. You may ask advice from septic pumping experts to provide long term solution to your issue.

Bovine Ordure!

[crazy88]

Thats how they work but often not adequate drainage installed.

Sounds to me like the grey water is being run into the sceptic perhaps? Should not need to have the sceptic attended to that often.

Crazy 88

[crazy88]

A 2" pipe!!! How on earth did they connect it? The right size couplings are designed for the tank and come with it in most cases.

Also I hope the drain now connected to is not going to a central system of standard drainage? Imagine that on an estate of 50 houses with every house running untreated foul waste down the middle of the road ( or side drains). Never mind the smell the disease risk rats etc would bother me. In the west we run foul waste to a sewer system leading to a sewage plant where it gets treated. Also if you have got grey water connected to the sceptic the chemicals from showering, cleaning etc will kill the natural bacteria needed for the sceptic to do its job. Putting paper down the toilet also buggers them up in time.

Crazy 88