Cesspit problem after 20 years.

[Scouse123]

We have a large detached house in rural Thailand built many years ago. We have decent sized private gardens where the hatches are for cesspit to the rear of the house.

 

We have three pits. Main one is shallow enough but leads directly to a secondarily pit which is deeper, maybe four or five rings. We have the concrete rings variety. These pits deal with two bathrooms, kitchen sink and washing machine. We have just re-routed the new washing machine for the waste water to go directly into the greener instead of cesspit.

 

The third pit is on the corner of the house in the back and as far as I know, services only one bathroom and isn't a big problem.

 

We have three bathrooms, a few sinks and a washer that gets a lot of use but there are only two of us living in the house! We both shower a lot.

 

For many years, the cesspit never presented a problem and we never had the water truck to come and pump out.

 

Yes, it has been quite rainy recently but not more than other years. My other half insists there is nothing wrong as she says many others around here having same problem but she says our ground has too much water.

 

I wish to emphasize that we have had the refuse water truck out to pump clear three times in the last couple of months, and it is  mainly water that seems to be getting pumped out.

 

Afterwards, it works fine for two weeks/three weeks and you can visually see it is empty. I keep saying to her and then there's the "silent treatment" that  we never needed a water truck in years before!

 

I am willing to dig up and even replace with septic tank, our rear gardens are decent sized but not oversized. I would say 30 feet length by 50 feet width.

 

Any ideas please? I don't mind whatever solution and can pay, I just want to solve this problem.

 

I cannot visually see a problem with it when said water truck has been but if I am paying 400- 600 baht a trip, I would sooner look at a long term permanent fix.

 

There are no mains drains around this area to connect to, or I would have done it years ago.

 

 

 

 

 

 

Edited June 29, 2021 by Scouse123

[VocalNeal]

There is a guy I know locally here who pumps his out. Because he has no where for the "overflow" to go. 

 

I would go first for the chemical option. Don't know if it will do any good but bung a packet or two of enzyme stuff in there. (flush down the toilet). That's about all you can do. If the ground is saturated the only other choice is to dig down the outside and fit a drain to a more remote septic field. Or...

 

 

[Yellowtail]

So what is the problem, the toilets are backed up?

 

Given the situation, I would wait until my decides it's a problem. 

[Scouse123]

1 minute ago, Yellowtail said:

So what is the problem, the toilets are backed up?

 

Given the situation, I would wait until my decides it's a problem. 

 

Yes, that's what has been happening, the toilets are unable to flush as cesspit is full of water.

[Denim]

You could make a gravel leach trench. Make a small outlet in the top of the cess pit then run a 1 inch  blue pipe to your leach trench. When the cess pit gets full the excess will drain away into the leach trench and evaporate. If no room for 3 trenches as shown just one along the border will probably work because Thailand being hot the water evaporates quickly.

 

[Scouse123]

6 minutes ago, Denim said:

You could make a gravel leach trench. Make a small outlet in the top of the cess pit then run a 1 inch  blue pipe to your leach trench. When the cess pit gets full the excess will drain away into the leach trench and evaporate. If no room for 3 trenches as shown just one along the border will probably work because Thailand being hot the water evaporates quickly.

 

 

I will look at that, we certainly have room for that.

[BritManToo]

22 minutes ago, Scouse123 said:

Yes, that's what has been happening, the toilets are unable to flush as cesspit is full of water.

So your water runoff is blocked.

Cesspit is supposed to be full of water up to the runoff pipe/outlet.

Emptying the cesspit will not clear the blocked runoff.

[Scouse123]

2 minutes ago, BritManToo said:

So your water runoff is blocked.

Cesspit is supposed to be full of water up to the runoff pipe/outlet.

Emptying the cesspit will not clear the blocked runoff.

 

See what you mean, it will just refill back up to the blocked runoff pipe, yes? And then back up again.

 

That makes sense, so I try get a workman to check the blocked runoff?

 

If I can find one to do it.

[billd766]

We have a 2,000 litre plastic septic tank at the main house with a liquid overflow pipe which drains water about 25 metres to just outside the gate. At least I think it does as the grass and scrub always seems to grow well there.

 

It was put in and buried when we had the house built 18 years ago and that is my best guess.

 

The septic tank IIRC is about 1.5 to 2 metres in diameter and does a good job with a visit 2 or 3 times a year from the "honey truck".

[billd766]

5 minutes ago, Scouse123 said:

 

See what you mean, it will just refill back up to the blocked runoff pipe, yes? And then back up again.

 

That makes sense, so I try get a workman to check the blocked runoff?

 

If I can find one to do it.

You will most likely need a high pressure water gun as well.

[Kwasaki]

1 hour ago, Scouse123 said:

 

Yes, that's what has been happening, the toilets are unable to flush as cesspit is full of water.

There's google web info on cess pit plans, your concrete rings are letting in out side water so you definitely need some investigating done to have a permanent solution.

Have read it's a lot to go through replacement with pvc tanks will help but the drainage lay out system has to be done correctly. 

 

[Susco]

1 hour ago, BritManToo said:

So your water runoff is blocked.

Cesspit is supposed to be full of water up to the runoff pipe/outlet.

Emptying the cesspit will not clear the blocked runoff.

 

I don't know Scouse's setup, but not all cesspit's have a runoff pipe.

 

I have 3 plastic septic tanks. Each tank has the liquid overflowing in what I call a seeping tank, which consists of a number of concrete rings with a lid but no bottom, so the liquid just seeps into the ground.

 

I think important is also that the seeping tank has an air vent, at least mine have

Edited June 29, 2021 by Susco

[BritManToo]

28 minutes ago, Susco said:

 

I don't know Scouse's setup, but not all cesspit's have a runoff pipe.

 

I have 3 plastic septic tanks. Each tank has the liquid overflowing in what I call a seeping tank, which consists of a number of concrete rings with a lid but no bottom, so the liquid just seeps into the ground.

 

I think important is also that the seeping tank has an air vent, at least mine have

They all work the same.

Inlet, solids collection tank, outlet.

If the outlet is blocked, your collection tank just fills with liquid until your inlet is blocked.

 

After 20 years the OP's outlet has probably collapsed.

Or someone planted a tree over it, and the roots have blocked the pipe.

 

Edited June 29, 2021 by BritManToo

[Denim]

32 minutes ago, Susco said:

 

I don't know Scouse's setup, but not all cesspit's have a runoff pipe.

 

I have 3 plastic septic tanks. Each tank has the liquid overflowing in what I call a seeping tank, which consists of a number of concrete rings with a lid but no bottom, so the liquid just seeps into the ground.

 

I think important is also that the seeping tank has an air vent, at least mine have

 

That worked for me in a previous house but we have clay soil here and the water wont seep away so I made a leach field for the grey water.

[bankruatsteve]

Maybe not an option for you... I put in new pipes to take the washer output and the kitchen sink output to the garden (instead of tank). That took care of issues for me. 

[sometimewoodworker]

1 hour ago, bankruatsteve said:

Maybe not an option for you... I put in new pipes to take the washer output and the kitchen sink output to the garden (instead of tank). That took care of issues for me. 

That’s exactly what we have, grey water goes directly into the garden, SWMBO is happy to direct it, only black water goes into the septic tanks, then the overflow goes into an underground leach field. 

[SomchaiDIY]

Important to check water table level near to septic tank before making any new work

 

Common problem at rain season with ring septic tanks if water table is high

Sealed plastic tank can fix this trouble if water table is not above tank outlet drain area

[Scouse123]

6 hours ago, bankruatsteve said:

Maybe not an option for you... I put in new pipes to take the washer output and the kitchen sink output to the garden (instead of tank). That took care of issues for me. 

 

Done that already with the washer, next is the sink.

[Saanim]

Why not to ask at the tessabaan, they know where to order people with a truck coming with long sucking pipe, piece of cake fro them...  

[Scouse123]

Just an update guys, I sorted the problem. I had to call the water truck out again after two weeks with the rains last month so I knew the problem was getting worse.

 

Anyway, I get the men in and I went counter to all their rubbish advice and insisted the dug up the back garden and I wanted a drain field.

 

We found the problem within thirty minutes. The entire piping of what was a poor attempt at a drain field which blocked, gunged up, and just not allowing any liquid through. Therefore, it was reversing back into the concrete pipes forming the pit and simply filling up with rainwater and household water.

 

We completely replaced all the piping and increased the size slightly, bought correct fitting connectors and right angled bends which had not been done properly, and amazed they lasted as long as they had.

 

We extended the drain field, dug down to a lower trench much further from the house, about 15 metres, we also punctured some of the pipes further away so water could seep into the ground as it flowed away, so we will see how that goes.

 

In total, pipes, connectors, bends, glues  and labour from neighbours was about 4500 baht!

 

I was expecting, until I looked at it, about 20,000 baht, and my other half said if we had got a company in, it would have been.