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Septic Sewer Systems

Septic Sewage Systems

We are having to re-examine and modify our Marketing Policy with regard to Septic Systems. Unfortunately, the average person; and most ‘professional advisers’ know/s nothing about septic waste water systems; any more than they know about the mechanical marvels of their modern motor cars.

 Recently, we have been castigated by several large families because our Products did not measure up to their expectations. Either they have tanks that are too small or th

ey are in clay soil or marshy [vlei] areas and they expect that a small [1,500 lt] plastic ‘torpedo’ septic tank will digest their combined waste

water and sewage. There is just no way that such a system will work. It defies basic science. It’s like trying to get a truck load of sand into a Mini Minor.


The sad thing – and we ‘feel’ for these customers, is that they have been advised by someone that the size of tank installed will be adequate [‘perfect’]. It is our experience that many architects, draughtsmen, builders, hardware retailers, tank manufacturers as well as [sadly] many municipal inspectors have scant knowledge of the limitations of septic systems; or that the modern diet is changing dramatically with the advent of ‘convenience foods’ with their highly refined and chemically complex [heart friendly and cholesterol free] fats.


We are consistently being approached by clients who have totally inadequate septic tanks, but they wish to buy and apply our products in the vain hope that they will overcome their defective sewage systems. Sometimes our Products do solve their problem short term, but they may not work; long term – they cannot be expected to; and we end up losing credibility and being bad mouthed by the affected customer.


In future we will hesitate to supply customers:


1.    Who send both grey and black water to their septic tank [thus causing hydraulic overload]

2.    Have septic tanks of inadequate shape and size for the number of Residents living in the house [organic overload]

3.    Have soakaways / French drains / leach-fields which are too small and are constructed  in unsuitable material. [causing the tank to surcharge/overflow]


However, we will gladly offer advice to these unfortunate people, because we realise that they, and their original designer / builder / planning officer was unaware – rightly or wrongly - of the limitations that govern the successful operation of septic systems; and although it is, not necessarily the fault of the owner – ignorance is a national excuse, and we will help to solve it as best we can.


A septic system is a very good [rural] sewage disposal devise, but it cannot cope with excessive loads. Usually the septic tank is too small.


Providing it is of a capacity sufficient to receive the load, and positioned in suitable soil, a septic system will work – well and trouble free -, for many years. In fact there’s nothing, apart from accidental damage to stop it !.


A septic tank should be cleaned and re-started every 15 – 25 yrs. Or until inorganic solids build up and reduce it’s capacity. Seaside cottages and houses in arid inland areas; plagued with dust


A tank that is ‘pumped’ frequently [once, twice or more a month sometimes] just does not have a chance of working, because each time it is ‘pumped’ most of the microbes essential for the degradation of sewage solids are lost to the recipient of the bulk effluent. [usually the local municipal ‘sewage works’]. This is progressive, until the tank becomes totally sterile – and ‘dies’.


Signage: From a cursory inspection of rural establishments, we are appalled at the lack of signage – especially in public resorts -  indicating a ‘septic tank’.  City dwellers do not know what septic tanks are; they are accustomed to the flexibility of municipal wwtw but they will usually respond to informative signage


Most city dwellers are blissfully unaware of the limitations of these ‘anaerobic bio-digestors’ [because that is what a septic tank is], compared to a municipal [wwtw]  waste water treatment works, which are designed to treat ‘mixed’ [commercial & domestic] effluent


We can [and have] written and supplied signage indicating that only human bodily wastes and the toilet paper provided is to be flushed down the toilet bowl. No newspaper, mealie cobs, fag ends or rubber goods [makes the poor little microbes cough !] So, if you have a septic system:  ASK US


The Septic System: Consists of:

1.    An adequately designed and sized septic tank [minimum two chambers],

2.    An overflow soakaway / frenchdrain / leachfield / grey water treatment plant  / permeable soil where the effluent is finally ‘polished’ before it re-joins the underlying water table..


‘Black’ water should never be re-used. It’s not safe: It is usually toxic


The ‘grey’ waste wash water [bathrooms, basins and laundry] should go directly to the soakaway. [or to a grey water treatment plant for ‘cleaning’ and, ultimately, garden re-use].


Only ‘black’ sewage waste water from the toilets and urinals and kitchen drainage [via a grease gulley/trap] should go to the septic tank


Calculation of load:  


1.    We do this by evaluating the number of residents, which dictates the capacity of the tank [the number of bedrooms, bathrooms and toilets make absolutely no difference – but the number of residents [people] do !]

2.    The permeability of the soil in which the soakaway is constructed – which dictates it’s relative size and length.


Invariably, we find that the equation has been calculated the other way around and the client/builder has decided upon the size of both the tank and the soak away or soak-pit [as is so frequently installed] to suite the pocket and garden; with no - or scant - regard for      family size or soil porosity. Usually cost/bottom line considerations are the deciding factor. You see, if the residence time is reduced, there will be insufficient time for the microbes to digest the sewage solids and some of the ‘unmentionable’ faecal material will be carried over from the septic tank to the soakaway where they will ultimately coagulate and seal the seepage holes between the soil particles, causing a blockage – over time - and the tank to overflow !


Such systems have been known to work trouble-free for a couple of years, then they say ‘howzit’ and fail; because they are inadequate for the load and too small. So you call that nice man from the Council to ‘pump’ the tank; and then your troubles really start in earnest, because the septic tank will ‘die’ as the microbes population is reduced.


Very few authorities have vacuum tankers with adequate ‘spate pumps’ [that will handle semi-solids]. They remove the liquid, but not the sewage sludge and fat that is usually in the soakaway - that is causing the blockage and overflow. Often there is a ‘run’ on municipal tanker services during the holiday seasons, and delays are inevitable, in addition to the accidental damage to gardens, the inconvenience and the odour. Nice for the family and visitors ?


Septic systems do not perform well under ‘feast and famine’ conditions. They are like diesel engines thriving under a constant load. If used for the odd week-end, you are advised to apply an additive [W-A-W] to ‘wake-up’ the microbes that are essential to degrade your sewage, and to boost them again when you leave the cottage. This can be done conveniently via the toilet bowl.  

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