I'm not clear how your title "clay sand" relates to what you ask in the question with "clay ground". Please edit your question and make this clear.

Also how does "sewage" fit into this? Are you meaning a septic system? If so, you'll need an engineer to evaluate your site and design an appropriate system. You'll absolutely need that in order to get a permit to build such a thing.

How is it being handled now?

You don't just drain sewage and let it soak into the ground.

Does this answer your question? How far should cement ring well be from wall

This seems to be this other question you asked but in a different form. If this is significantly different, please clarify what this one is about.

You can't drain effectively in clayey soil, actually, it might dissipate the water it contains into the septic field. As pointed out on the other thread mentioned above, you need a civil engineer to look into this matter. Trails and errors do not work for this case. Good luck.

Sand is used in filters… So you really need to explain your situation clearly ´cos it’s muddy at the moment.

I've updated the question to make it clear now

@JACK - How can I handle the sewage water(1800L per day) ?

@jwh20 - I'm worried about grey water(Sewage) comes from building just wondering how to handle that ?

@r13 - You are right ,I'm bit worried on how to handle this sewage water issue ?

@SolarMike - Ground is completely clay and just wondering how to handle this grey water

Water from sinks and showers is called grey water, water from toilets is called black water. Both are called sewage. If you understand the difference then you should clarify, in the original question not in a comment, what you are dealing with.

Sorry it's grey water

No matter the color code, it seems to me you need a drain pipe leading to a drain field or linking to the public sewage line. That's why you need an engineer to determine the final destination, the route, and what kind of permits are required. I am puzzled why the drainage issue wasn't brought up before the building construction, or reviewed during the permit process. Don't you need the permit to build, and a permit for use? You must be located in a free country then.

You have created a very difficult and perhaps impossible problem for yourself by building or acquiring a building without a sewer connection and an unknown capacity for a septic system. It's not clear where in the world you are but in most developed nations you cannot just build a building and then hope there is a way to get rid of sewage. That needs to be addressed up front before you start construction.

I have got building permit but it's just that it'll take decades for local body to install sewage line. TBH there's no sewage link in the town at all. Neighbhours are mostly have a famil but I have built an apartment with three houses and three families hence the complexity

It is what it is, I just would like to find one working solution and invest in it.One of my neighbhours bored the ground upto 120 feet.. its plain clay. to make the matters worst the ground water level is at 7 feet. Just looking to know some insights to solve the issue

One method could be the cheapest to solve your problem, but again, you need someone who has the knowledge to design it. Remember old-style water filtration system - dirty water running through layers of filters consisted of gravels and sands to catch the larger particles and eliminate smells, then the clean water comes out at the end/bottom, which can be released to the ground, or a pond, to evaporate naturally, or pumped away. You need to confirm that the local permits this approach though.

@r13 - The problem is it's 1800L per day , I'm just wondering how I can release the water to ground. It won't absorb as the ground is clay. There's no near by water body to pump away the cleaned grey water. Just confused how can I go about ?

@SolarMike - Will release filtered , clean grey water and besides the ground water is salt water so nobody is using that as well

So you are located by the oceanfront. How far is the free unclaimed land by your buildings?

@r13 - It's some 10 kms away from sea shore. I have 5 feet empty space on the left side of building parralel to building wall(60 feet).so overall I will have 300 sq.ft unoccupied free space

Have you actually run a percolation test on your property? Also, I take it this is domestic greywater (from sinks, showers, and laundry), no?

@ThreePhaseEel - No not yet but as clay ground , I assume it'd fail

Not an answer, but a possible mitigation - reduce the amount if grey water being produced. I have have found 7 litre/min shower heads and 3 litre per minute tap "tips" have very significantly reduced our water consumption. If your toilets are using more then about 7 litres per flush there are significant savings there as well. (Also apparently front loader washing machines are much more efficient then top loaders)

Baby shampoo drastically increased the drainage in my backyard; it used to flood several times a year, now it's only slightly pooled once this summer, despite huge events.

I'm worried if I drain the grey water near by home , the building could tilt ndtv.com/bangalore-news/… I'm worried I'd like some wisdom