septic tanks

jtk174

Just wondering if anyone else on the N.I. forum has a septic tank?

Been having a bit of bother with mine this year and for the first time in a few years, I was here when the Water service contractors emptied it.
Instead of lifting the manhole cover, they removed a cap from the inlet vent and emptied from there.

I can't see how all the sludge can be removed from the tank by doing this and more importantly, I can see this leading to a build up on the outlet side and blockage of the drain field.

Any experience of this ?

RTNI

I and my parents have a septic tank (or to be more precise mine is one of these new treatment plants with reedbeds).

In my experience, the metal manhole cover is removed and the hose placed into each section to suck the sludge out. I would agree that if the hose was only placed in the first, primary settling chamber then the subsequent chambers would not be emptied and could block the output to the soakaway. I am not sure however how high up the exit point would be to the soakaway so unless there was a load of sludge in the last chamber (which there shouldn't be) then it may be another problem?

GlynD

The sludge should all be in the top chamber so I can't see why draining it this way would be wrong.

A wee tip. If you're having problems with your septic tank it's likely because it's too small. That causes most problems with these.

oldhand

Also septic tanks should not be completely emptied of sludge as some is needed to help in the digestion process of the new waste effluent entering the tank.

endadmcc

When I had my septic tank emptied last year by the water service they left a receipt stating how many ltrs had been removed .

A.L.D.A

GlynD wrote: »

A wee tip. If you're having problems with your septic tank it's likely because it's too small. That causes most problems with these.

Biggest problem I believe is modern detergents.

jtk174

Thanks for the replies.

I have been doing a bit more research and several items that say never desludge the tank via a vent.
For anyone interested here is a leaflet with good info;

http://www.fwr.org/wastewat/Septic%20tank%20systems%20-%20users%20guide.pdf

GlynD

A.L.D.A wrote: »

Biggest problem I believe is modern detergents.

Which are added to try and speed up degradation, because the tank is too small to cope with the volume of waste.

A.L.D.A

GlynD wrote: »

Which are added to try and speed up degradation, because the tank is too small to cope with the volume of waste.

No. You use them to kill all known household germs and down they go and do their work on the bacteria in the septic tank.

GlynD

A.L.D.A wrote: »

No. You use them to kill all known household germs and down they go and do their work on the bacteria in the septic tank.

If a septic tank is functioning correctly it needs no additives. That's the whole concept.

saverbuyer

GlynD wrote: »

If a septic tank is functioning correctly it needs no additives. That's the whole concept.

ALDA gets the operating principle.

You said.

Which are added to try and speed up degradation, because the tank is too small to cope with the volume of waste.

Detergents aren't additives. ALDA is saying we use them in household cleaning and they get washed into the tank. They are a by-product of household cleaning; they aren’t "intentionally" put in the tank to “speed up degradation”. That would actually have the opposite effect.