It's a good idea to know as much about septic tanks as possible before choosing the right one for you. there are many factors to take into consideration. Read our latest post to help clear some of the issues up!
Septic tanks are a way of treating wastewater and sewage disposal for areas that are not connected to the mainland sewage system. In a sense, they can act as a self-efficient method to take care of wastewater without the complication and expense of a full fledge sewage system. However, in some cases, once these septic tanks are built they are seldom again checked and maintained, and therefore often run into problems that cause pollution and health hazards for the people nearby. For this reason, strict laws exist in most places to keep a check, and set minimum standards for these septic tanks.
A very common problem, as with any other water-body that’s underground, is the overflow of water after a period of heavy wet weather. Excess in the inflow of water into these septic tanks will cause the wastewater inside to overflow - causing it to reach the surface of land and leak into nearby pipe systems. As any slight disruption in the quantity of liquid inside the septic tank will cause it to overflow and essentially hinder its working mechanism, one thing can be said for sure that these tanks are not a long-term or a smart solution to the problem of roof water storage.
Most problems in septic tanks occur not directly because of a flaw in the septic tanks, but rather a faulty soakaway drain field. The period of time that your Septic tank would function for you depends upon a number of factors: the nature of the soil, the climate and weather in the area where the tank is located (such as heavy spells of rain), the height of the winter water table, and the corrosion of the septic tank itself. Whichever reason contributes to its failure; septic tanks are bound to fail sooner or later. It’s simply a matter of when.
How to identify if your septic tank is not functioning properly? The following signs will help you identify a faulty septic tank:
- Some remains from the septic tank will start to float on the ground surface (definitely not where it’s supposed to be!)
- A heavy smell rising from your septic tank (perhaps the most prominent indicator)
- Noticing nearby water systems being contaminated with effluents as the waste leaks into nearby pipes
- Slow flushing of toilets (as the build-up in the tanks is already overloaded)
- Bubbling in the drains
- Dunks near the surface of the septic tanks
- Overflowing of toilets
- Water overflowing near the hookups around your washing machine
- Water enters and empties slowly into drains after you shower
- Your drain inspection chambers, which should otherwise be empty, have effluent standing in them
Once you’ve noticed the signs of a septic tank malfunction, it’s time to identify the reason for it. This may be any or even a combination of the following:
- Negligence in the maintenance of the septic tank
All septic tanks must be emptied frequently, at least once a year as a minimum. As imaginable, they hold tonnes and tonnes of sludge and another effluent, and if not cleaned and emptied on time, all the buildup would disrupt the functioning of the tank. This is quite simple to understand: when excess gunk accumulates on the bottom and surfaces of the tank, the wastewater can no longer seep through the air spaces in the soil, thereby not being able to empty the tank and make more space for further inflow. This causes the liquid entering the tank to overflow and eventually reach the surface of the ground, thus emptying of the tanks is a crucial process without which they cannot function.
- Improper construction of the septic tank
To understand this, you'll need to know a little bit about how basically a septic tank works. To put it in the least complicated way - an ideal septic tank is supposed to be built up to the aerobic part of the soil (little spaces in-between the soil that allows air to seep in) and the aerobic soil allows the aerobic bacteria to function. These bacteria naturally digest the effluent by slowly degrading them.
However, in instances where the tanks are constructed further below the aerobic layer of soil (usually about one meter) entering into the anaerobic layer, this is where the problem starts. As no air is able to seep into the bottom surface through the soil, as the soil has now ‘airways’ through which air can enter, the bacteria down there have to work without oxygen. When they work anaerobically, they produce a black slime as a product of digestion of all the effluent. This slime in turn blocks the surface of the soil, preventing any wastewater to seep into the ground.
What’s troublesome is that many companies today that offer to construct a septic tank aren’t aware of this basic functioning of the tanks themselves. Hence they construct tanks that are well below the desirable depth of the tanks, and consequently, the tanks are more or less bound to run into problems sooner or later.
- 3. Condition of the soil in which you construct your septic tank
It is crucial to first fully see the nature of the soil in which you decide to build your septic tank. As the mechanism relies completely on seeping through the soil to allow inflow from the top, it is essential that the soil allows this seepage of effluent to occur. If the septic tank is constructed in clay or clay-based soil, the porosity (the ability of substance to ‘pour’ through the soil) is very low. The airspaces between the soil particles are so tight that wastewater cannot seep through easily. Therefore, the effluent blocks the lower surface and keeps on accumulating further inflows right on its top without seeping any lower - this, in turn, causes overflows and disruption of the entire mechanism.
Even with a somewhat sandy soil, as mentioned above, the tanks are often built too deep down which causes bacteria to work anaerobically and produce a black slime, which blocks the airspaces inside soil and doesn’t allow movement of the wastewater. It is extremely common to find a very high ratio of effluent to the liquid inside septic tanks, and even sewage systems, which eventually deprive the soil of its ability to soak liquid any further. People might often try to fix this with an artificial pump to try and ‘push’ the effluent down further into the ground. However, this makes matter worse: as the tank is dug deeper, even lesser oxygen reaches the bacteria and so degradation of the effluent is even slower - and not to forget greater production of the black slime. So pumps in a way only make matters worse.
Some people might try a different approach and add packets of bacteria into the ground to aid the degradation process and make room for further inflows into the septic tank. But this too can do nothing to restore the soil’s ability to soak up liquid and hence fails to make an actual difference, much less help the situation.
- 4. The level of water table
If the winter water table becomes higher than the septic tank, then the water ‘finds its own level’ and this causes problems for the functioning of the septic tank. The pouring of water from the water table to inside the septic tank not only reduces the space available for inflow to enter but also causes solids to mix in with the septic tank, causing the resulting effluent to be filled with substances that reduce the porosity of the soil. As the soil’s porosity reduces, it cannot soak up much of the effluent causing further problems and eventually overflow of the septic tank. Hence it is very important to first carry out a thorough examination of the water table level before deciding to construct a septic tank at a place.
- Weakening of the septic tank
No matter what you build your tank out of - brick, metal, or even plastic - it is bound to deteriorate in a matter of time. This is because the nature of the waste and effluent is highly corrosive, and so it corrodes the surface of the tank from day one. The degradation process of the effluent results in the production of hydrogen sulphide gas which then mixes rapidly with water to form sulphuric acid.
Needless to say perhaps, sulphuric acid corrodes all surfaces alike, even if it’s made out of the most expensive metal! When the surface of the tank starts to corrode, water begins to seep down below tank into the soil. But that’s not the worst part: as the water goes down, solids and other particles enter the septic tank. This means that the volume inside the tank to contain the wastewater and effluent is reduced greatly, concentrating the liquid inside the tank until it is no longer able to hold anymore and the porosity of the soil is highly compromised. This then eventually leads to overflowing of septic tanks.
- Sodium binding in the soil
When sodium salt particles are present in the soil, the resulting mixture between the two produces a chemical known commonly as sodium binding. This means that the clay particles are now stuck together in such a structure that there is no longer any space between them - for air, water or seepage of any kind. This results in the effluent accumulating above the surface of the tank which keeps on accumulating until the tank can store no more and thus it overflows.
- Dumping the septic tank with more than what it can handle
It is possible that multiple numbers of houses share the same septic tank. It is common sense that the tank can store only up to a specific volume of wastewater, and when the quantity of inflows exceeds that level, the tank is bound to overflow. The same can be the case with too many people inside the same household using the septic tank.
How to solve the malfunctioning problems of a septic tank:
- Install a new soakaway drain field in a different part of the ground
- You can buy a conversion kit to fit inside the septic tank
- You can transform your isolated septic tank into a whole system of a three-step sewage treatment unit. The septic tank can act as the first stage of the process.