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Septic Tank Maintenance: How Does a Septic Tank Work?

20th February 2023

Septic tanks essentially provide private drainage for sites and buildings not connected to a mains sewerage system. Contrary to popular belief, they’re not just for temporary construction sites or homes in extremely remote areas. Rather, they can be found in up to 500,000 properties across the UK, with many homeowners unaware that they even have one.

In January 2022, the UK government issued a new set of regulations on septic tanks, bringing the issue to the fore. It is now mandatory to either fully replace septic tanks that discharge into surface waterways or to redirect your wastewater to a designated, compliant drain field. With this in mind, you may be wondering “how does a septic tank work?” and “what can I do to maintain my septic tank?”. This blog should answer your questions and quell any pressing concerns, explaining how a septic tank works and delving into septic tank maintenance.

What Is a Septic Tank?

Consisting of a large concrete, plastic or fibreglass container that is typically buried underground, septic tanks collect all the wastewater that runs out of your bathroom, kitchen and other drains via the connected pipework. Nevertheless, they do much more than collect waste. In fact, they are designed specifically to treat your wastewater in situ. This helps to keep the area around your home or business clean and hygienic, in addition to protecting nearby waterways from pollution. But how does a septic tank work? Find out more below.

How Does a Septic Tank Work?

Septic tanks are sedimentary systems. This means that, over time, the solids contained in your wastewater settle to the bottom of your tank as sludge, before the remaining liquid (the effluent) is discharged into your drainfield. If your wastewater contains any fats, oils and greases (FOG), they will float to the top of your tank, where they will settle as scum. The bacteria in your tank should naturally break down any solid waste, although the middle wastewater layer may still contain smaller waste particles.

Both the inlet and outlet pipes are shaped like a T, in order to prevent both the sludge at the bottom of your tank and the scum at the top of your tank from seeping into the outgoing pre-processed water. Once this water has left your tank, it will be dispersed evenly to filter through the surrounding soil. The soil will then naturally remove any harmful bacteria, viruses and nutrients from the effluent as it trickles and percolates through the ground, into underground watercourses.

Of course, the sludge that accumulates at the bottom of your septic tank over time will need to be periodically removed, which brings us nicely onto the topic of septic tank maintenance.

Septic Tank Maintenance: How to Maintain Your Septic Tanks

It is your responsibility as the homeowner to adequately maintain your septic tanks, ensuring that they do not impact the local environment. If too much liquid accumulates in your drainfield, this can result in flooding and could even cause sewage to come up to the surface, producing hazardous waste and potentially blocking your sinks and toilets.
If you have already noticed such a blockage or any suspicious smells, it’s best to get things checked out straight away. Nevertheless, there are several essential septic tank maintenance steps you can follow outside emergency situations to keep your system running in top condition as well.

Inspect Your Septic Tank Frequently

Considering how a septic tank works, inspections are recommended at least once every three years. You should always get your systems checked by licensed professionals, who will be able to tell if it needs to be pumped. Pumping tends to be necessary once every three to five years, although the exact timeline will depend on both the capacity of your tank and the total amount of wastewater generated.

In addition to the above, it’s a good idea to check your pumps, float switches and other mechanical components on a more regular basis – usually once a year.

Reduce Water Consumption

The more wastewater your household produces, the more quickly sludge will accumulate in your septic tank system. As such, if you’re looking for simple tips on septic tank maintenance, it may be a good idea to try to reduce the amount of water you use and dispose of. This becomes increasingly important when you consider that pouring too much water into a limited-capacity system all at once could lead to the sludge at the bottom of your tank being stirred up, into the effluent and out into the surrounding environment.

Try to limit the number of times you flush the toilet and be mindful of the water you use. Opt for a shower over a bath and always use plugs in your sinks and basins. Your household appliances, such as dishwashers and washing machines, may also have an eco-mode.

Dispose of Waste Properly

Never flush anything you shouldn’t into your septic tank. The bacteria in there can only digest organic waste, so nappies, sanitary towels and face wipes are all a resounding “no”! They will simply block your drains and ruin your system.

Likewise, although your septic tank is designed to handle a small amount of fats, oils and grease, which will naturally rise to the surface, too much build-up could lead to serious problems, so avoid pouring any of these products down your drains.

It’s not just the typical culprits you need to be aware of, either. As explained earlier in the “How does a septic tank work?” section, septic tanks use bacteria to operate. As such, you’ll want to avoid the use of any harsh chemicals that could destabilise the delicate bacterial balance in your tank wherever possible. Look for bleach alternatives wherever you can but don’t be afraid to use hydrogen peroxide if you really need to. It’s always possible to top up the bacteria in your tank.

Maintain Your Drainfield

The drainfield – the area into which your effluent water finally flows – is often an overlooked aspect of septic tank maintenance. Nevertheless, keeping it in top condition is of utmost importance. Avoid parking or planting trees on top of the area and ensure that other drainage systems, such as your gutters and rainwater pipes, run into another area to prevent a sudden build-up of excess water.

Our Septic Tank Services

At Cotswold Drainage, we specialise in providing professional septic tank services. So, if you need help with septic tank installation, removal or replacement, get in touch. We can carry out inspections, sort out any soakaway problems and offer free, impartial advice on how a septic tank works and what you can do to maintain it.