Septic tank overflowing

[Timmy_T]

Hi,

We moved into a property about 9 months ago which has a large brick built septic tank (it used to service 2 cottages, but now just ours). The previous owners said they'd never had any problems with it and had never had it emptied in 10 years.

After several days of really heavy rain, we noticed a slight smell in the garden, and then found that the tank was full to the top. Taking the manhole covers off, I found both the inlet side and outlet tanks full as well. The tank discharges the grey water into a ditch in our paddock, which still appears to be running, although when I tried to push drain rods up the discharge pipe I found it was only 3 ft long, and the water seems to seep through to it through the ground, as if by magic!

Does this sound like a case of just needing the tank emptied, or is there a problem with the discharge? Is it possible it's just been overwhelmed with all the heavy rain? Should there be a pipe running all the way to the ditch, and is it possible it has collapsed?

I'm really sorry that I don't know how these things should work, but I'm just a little confused that there still seems to be water discharging from the outflow pipe into the ditch, but there doesn't appear to be a pipe connecting it to the discharge pipe from the end of the sewage tank (there is one there as I managed to get about 20ft of drain rod down it!)

I hope this makes some sort of sense to someone!

Many thanks

 

[Timmy_T]

Maybe I should add that as a temporary stop gap measure, I've run 20m of garden hose from the outflow (grey water) chamber of the tank to the ditch where the grey water discharges to, and have had it syphoning water out for about 12 hrs now. This has dropped the level in the tank by about 6", but is obviously not a permanent solution!

 

[merlin50]

you must be very careful what you put into a septic tank no bleach or other nasty things. get it emptied and start from fresh put a bit of builders lime in it. if it overflows again then the soakaway system may have failed. it should be almost full to the top when working properly.

 

[regsmyth]

You need to work out is it a septic tank or a cesspit?

A cesspit shouldn't discharge - it just fills up and then needs emptying (pumping out).
A septic tank is supposed to allow biological processes to work, breaking down the solids and producing a relatively clean fluid that can run along an exit pipe and soak away into the ground.

When tanks get too full, the solids/sludge gets into the outflow pipe and clogs up the joins/holes where it should leak out.

I don't think your outlet should be going into a ditch.

You should get some good advice from a local drainage company, plenty of info on line too.

 

[Hugh Jaleak]

Firstly, get it emptied. Assuming it is a septic tank, whilst the liquid will drain off (eventually), the solids will remain and break down into sludge which needs to be removed periodically. As Reg has said, infrequent desludging can result in too high a concentration of suspended solids in the outflow, this in turn then sludges up the leachfield causing it to stop working. Every drop of water going into the tank needs to drain out again.

Outfalls aren't permitted to be drained into a ditch anymore. Whilst there are plenty of systems out there built like that, the Environment Agency do not like the idea and will make you spend a lot of money fitting apparatus to the outflow so the discharge is to their liking.....

It is also illegal to empty a septic tank unless you are a licenced waste carrier! DIY attempts with hoses or pumps, or getting the local farmer in with a slurry tanker will upset the E.A. !

 

[Timmy_T]

I think it's a septic tank, it has a large center chamber (5ftx10ft ish), rectangular in shape, brick built, covered with concrete sleepers. Inside is a lot of "stuff" covered with a muddy crust. At either end is a manhole cover over smaller chambers (about 3ft square), one end that you can see lots of dirty slurry, the other end full cleanish grey water.

It does soak away into a ditch, but the local authority is aware of that as our solicitor checked it was properly registered when we bought the property. I'm not discharging the slurry into the ditch, just the grey water end product. After about 48 hrs of syphoning the water level has dropped to well below the top of the chamber, and is constant at about 9" lower than it was.

Could the ground conditions be a factor as it has been extremely wet here. All the local land is very wet, with surface water lying about everywhere. If the ground is saturated, would it be more difficult for the grey water to soak away, causing it to back up?

 

[merlin50]

its a septic tank but it will not work if the ground is waterlogged, i have lived with septic tanks most of my life, lime will help with the smell and make it work better. a pump in the end chamber will help in the wet weather.

 

[Nige F]

I think it's a septic tank, it has a large center chamber (5ftx10ft ish), rectangular in shape, brick built, covered with concrete sleepers. Inside is a lot of "stuff" covered with a muddy crust. At either end is a manhole cover over smaller chambers (about 3ft square), one end that you can see lots of dirty slurry, the other end full cleanish grey water.

Could the ground conditions be a factor as it has been extremely wet here. All the local land is very wet, with surface water lying about everywhere. If the ground is saturated, would it be more difficult for the grey water to soak away, causing it to back up?

Yes it`s a septic tank - yes the ground is waterlogged - yes it wants emptying and re starting - you can get dry powdered enzymes to put down the drains to get it working - All the other posters are correct

 

[Timmy_T]

Thanks guys for all your help, just thought I'd give you an update.

Had a local firm round to look at it who said "Your soakaway is shot, you can either have it re-dug/renovated for £8k, or you can have a treatment system installed for £4k!". After a short time my eyes stopped watering and my chin lifted from the floor, thinking where on earth do I find that sort of cash!

So I decided on a second opinion, from another reputable local firm (as was the first one). This time, the chap advised me to have it emptied and get the outflow pipe jetted out, for £250. Must be worth a punt, I thought, and hey presto, it worked!!

In fact, after he had some looking around the place, he found that the tank does infact discharge into our ditch, but not where I thought (the one I found was the rain water run off), but close to it.

So all in all, it now seems to be resolved, saving me £3750 from the original quote - fingers crossed!

 

[wastetech]

It is illegal to discharge septic tank effluent into a ditch. Your existiong permission will be to a soakaway ONLY. Even if septic tank effluent discharches accidentaly into a ditch you are liable under the Water Resources Act 1991 and the fine is set at max. £100,000.
You may well have a case against the second reputable local firm.

 

[Mrdjc]

As far as I'm aware all NEW systems must comply to regulations.

Existing systems that were in place before the regulations can remain functioning until they require replacing or are uneconomical to repair.

But if you are modifying or renewing it you must comply to the new regulations.

Spot of bother if you decide to have a new-build and opt for planning permission and highlight using the existing tank, as they will more than likely say to replace it so it complies to the new regulations.

My parents own a rural property with a septic tank which its overflow discharges into a ditch in our fields, goes into a reed bed about 100M beyond the discharge point and then ends up in the sea, it is also a concrete/brick thing from 1960 or something along those lines, needs emptying once every 7 years or so, and just serves the one house.

We also have a new plastic septic tank for holiday lets which runs through the field with perforated drain pipe laying on a bed of soak away material and the end protrudes into a ditch, the same ditch as the old septic tank.

Never had any issues with planning, but in order to renovate another old building on the property we require replacing the old concrete/brick tank, or place a new one alongside it.