Septic Tank Problems
A septic tank system consists of a storage tank with two or three chambers to separate the solid waste from the liquid waste allowing the liquid waste to be discharged in to a drain-field (soak-away) or a treatment unit.
Generally there are two types of septic tanks; onion shape and low profile cylindrical (or low invert) septic tanks.
Onion shape tanks
These are constructed by Klargester and conform to BS regulations. These tanks are made with glass fibre and have a baffle to separate the solids from the liquid. Klargester tanks must be installed with a concrete base and backfill.
Here are some common problems with the Onion Septic Tank
- Baffle collapse, older models of Alpha septic tanks or onion tanks had a common problem with the baffle that hangs in the middle of the tank detaching from the hull and falling in to the tank, this would cause the waste from the inlet side to mix with the water and eventually find its way in to the soakaway causing blockages
- If not installed with a concrete surround these septic tanks are prone to collapse.
- blockage due to poor venting, as main vents are situated under the main lid these can be prone root infestation.
Low profile (invert) cylindrical septic tanks
This type of septic tank has a lower invert level than the onion shape, making it easier to install because the excavation area is smaller. They are also very good for installation in areas with a high water table, the construction is of glass fibre and because of their twin chamber construction they are very clean septic tanks.
Here are some common problems with the Low profile septic tank
If it is a older tank using clay pipework the t pipe outlet can be easily knocked off leaving you with a straight outlet pipe that allows all the sludge waste from the surface of the to exit down to the soakaway causing blockages.
Because this type of septic tank is more efficient at compressing the sludge waste the tendency can be to leave large amounts of time between emptying intervals, this can cause the sludge waste to solidify at the bottom of the septic tank making it very difficult to de-sludge
Common problems with septic tanks
It’s true to say that most septic tanks and soakaways develop some sort of problem during their life-time, whether associated with overflowing, blockages or bad odours.
Every septic tank system has a soakaway attached to it and the most common problem with a septic tank is the soakaway failing or becoming blocked. Unfortunately every soakaway will fail at some point, and the same is true for septic tanks and wastewater treatment plants. The main reasons for soakaway and septic tank failure is usually a combination of poor maintenance, deterioration of the septic tank and drainage pipes - especially if they are clay pipes.
How will you know if your soakaway has failed?
Here are the most likely symptoms:
Effluent surfacing and leaking out of the ground.
Bad odours from the wastewater.
Septic tank backing up quickly after emptying.
Overflowing bathroom and kitchen gullies.
Inspection chambers with residual effluent.
What do you need to do to ensure your septic tank and soakaway or drainage field works properly?
This mainly comes down to maintenance – like changing your car oil, all septic tanks should be emptied at least once a year because if the sludge from the septic tank starts to reach the soakaway or drainage field, it will cause a blockage and fail. All septic tanks need to be emptied whether they are Onion shape or low profile cylindrical shape.
How to construct a soakaway?
For information, please see our Septic Tank Soakaway page.