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When choosing a biological treatment plant for a private house, one of the most important questions is a very practical one: where should the treated wastewater go? Even if the plant treats very well, the final solution always depends on the conditions of the specific property, the soil, the terrain and the discharge options.

To make the choice safe and clear, below we have summarised the 3 most popular options that are most often used with AUGUST plants.

How to tell which option is most suitable

Before you choose a discharge method, it is worth assessing 4 things:

• the soil composition and its ability to absorb water (sand usually “takes” water better than clay)

• the groundwater level in different seasons, especially in spring

• the terrain and whether pumping is needed

• nearby drainage features, such as a ditch or land drainage system

The more precisely you understand this, the lower the risk that after rain or in spring the system will start “living a life of its own”.

1) Infiltration field

Infiltration is one of the most popular solutions because it is simple, quiet and visually unobtrusive. The treated water soaks into the ground, where it is filtered further and dispersed over a wider area.

This option works best where the site drains well and the groundwater is not high. If the soil is heavy and wet, however, infiltration can become slow, and then another solution or additional technical components need to be planned.

2) Ditch or land drainage system

If there is a ditch or land drainage system near the property, the treated water is often discharged straight into it. This is especially convenient if the terrain allows a natural flow or a pumping station can be installed.

It’s important to make sure the discharge is permitted and complies with local regulations. In practice this also means the treated water is visually clean, odourless and free of visible impurities.

3) An open water body, such as a pond

The third option is to discharge the treated water into an open water body, such as a pond. On some properties this is a good way to maintain the water level in drier periods, but you need to be especially careful about the impact on the environment and local conditions.

If you choose this option, take a conservative approach: assess the volume of the water body, its water exchange and whether the pond is closed or connected to other watercourses.

AUGUST treatment quality

AUGUST plants are CE certified, and the treated water parameters (according to certification) are usually very high, for example:

• BOD₅ ≤ 5 mg/l

• Suspended solids ≤ 5 mg/l

• Ammonium nitrogen ≤ 1 mg/l

In practice this means the water is visually clean and odourless after treatment, which opens up several safe discharge options.

If you want to be sure where to discharge treated wastewater on your property, the quickest way is to assess the soil, terrain and discharge options on site. We will help you choose the most suitable solution and plan the whole system so it works reliably after rain and in spring too.

A customer from Tīnūži came to us with a clear goal: to set up the property so that it would be as independent and convenient as possible in everyday life. Until then the house had temporary solutions that worked, but in the long run the customer wanted stability and control over both the water supply and the sewerage. So we agreed on the full scope of work, so that the customer wouldn’t have to look for several contractors and everything would be sorted out in one project, with one responsible team and a clear timeline.

Water connection from the borehole to the house

The first step was to provide a permanent water supply from the customer’s own borehole. Once the borehole was finished, we connected and plumbed in the system, prepared the necessary technical equipment and ran a water pipe about 30 metres from the borehole to the house. To make sure the water supply works safely and evenly, we checked the pressure, the watertightness of the joints and that the system is easy to access for maintenance. As a result, the customer got an independent water source – a practical solution where a central connection is unavailable or not cost-effective.

Sewerage with an AUGUST AT-6 and a pumping station

For the sewerage system we chose the AUGUST AT-6 biological treatment plant, a compact and reliable solution for a family home. To ensure stable operation and convenient discharge of treated water in these conditions, we included a pumping station in the system. This allows the treated water to be discharged in a controlled way even when the terrain or distances require an additional solution.

During the work we also explained the key principles of use to the customer, so the system works without surprises. These everyday habits help the most:

• no wet wipes or hygiene products in the sewer
• don’t pour large amounts of fat and oil down the sink
• use aggressive chemicals sensibly, especially in large quantities

The result: a self-sufficient, well-organised property

Now that the work is complete, the property has both a water supply from its own borehole and a sewerage system with an AUGUST AT-6. The customer got a solution that is clear, predictable and convenient in everyday life. And compared with holding tanks, this kind of solution helps cut down on having to arrange regular pumping out and plan for unexpected costs.

If you also need to sort out your water and sewerage, get in touch. We will recommend the most suitable solution for your property and prepare a clear plan with costs, timelines and next steps.

If your property still has an old septic tank, holding tank or a sewerage system built long ago, sooner or later there comes a point when dismantling the old sewerage system is the sensible step. Usually this is not “because you want something new”, but because the old system starts causing everyday problems and costs that are no longer reasonable.

When is dismantling justified?

The first signs usually appear gradually. At first it may seem like “nothing much”, but over time it becomes clear that the system no longer works reliably. The most typical signs are:

• a smell in the yard or near the tank lid

• more frequent pumping out than before and rising costs

• overflows after rain or in spring, puddles and waterlogged areas

• suspicion that the tank is not watertight or groundwater is leaking in

• an old infiltration field that no longer absorbs water and causes repeated problems

In such situations people often try to repair the old system, but in reality this tends to be a short-term fix. Old septic tanks and holding tanks crack, infiltration fields clog, and if the soil conditions are unsuitable, the problems come back. That’s why it is often better value to sort everything out once and switch to a modern solution such as a biological wastewater treatment plant.

How is an old sewerage system dismantled?

It’s important to understand that dismantling is not just “digging out the tank”. The right approach usually starts with emptying the system and removing its contents, so there is no risk of pollution during the earthworks. The system is then disconnected from the house sewer, and we assess what to do with the structure. Depending on the situation, the tank can be lifted out or properly neutralised and filled so that no subsidence occurs in the future. Finally, the pit and the ground are levelled so that the site is safe and ready for the next solution.

Why do people often switch to biological treatment?

Very often dismantling is done together with installing a new system, such as a biological wastewater treatment plant. This gives you predictable operation, less risk of odours and clear maintenance costs in a single project, and avoids a situation where the old system keeps getting “patched up” without a lasting result.

Biological wastewater treatment is one of the most effective ways to manage household sewage safely in a private house and reduce the impact on the environment. It is based on a natural process: microorganisms break down the organic matter in wastewater so that the treated water can be discharged safely (in line with the chosen solution and local conditions).

In this article we explain simply, step by step, how biological wastewater treatment works, what the owner can check, and why correct use + maintenance determine whether the system works without odours or surprises.

In short: the 5 stages of treatment

1. Wastewater collection
2. Mechanical treatment
3. Biological treatment (microorganisms)
4. Settling (sedimentation)
5. Discharge of treated water / use for technical purposes

1) Wastewater collection

It all starts with household wastewater from the house (toilet, sinks, shower/bath, washing machine and dishwasher) flowing through pipes into the treatment plant. At this stage, the most important thing is a correctly built connection and gradients, so that the flow is even and blockages don’t occur.

2) Mechanical treatment (removing larger impurities)

Before the biological process, the wastewater passes through a mechanical stage, where larger impurities that don’t biodegrade are separated out (e.g. some fibres, pieces of plastic, etc.).

This stage is important because it protects the system from mechanical faults and helps the next stages work more reliably.

3) Biological treatment (microorganisms do the main work)

This is the most important stage. In the biological zone, microorganisms (activated sludge) break down the organic matter in the wastewater. To make the process efficient, the system usually provides conditions that help the microorganisms work steadily (e.g. aeration/oxygen supply, the right flow regime).

What does this mean for the owner?

If large amounts of aggressive chemicals or insoluble waste regularly go down the drain, the biological process weakens, and then odours, poorer treatment or faults appear.

4) Settling (sedimentation)

After the biological stage comes settling, where the heavier particles settle out and the treated water separates and moves towards the outlet. This stage helps produce a clearer flow of treated water and reduces the amount of solids entering the discharge system.

5) Discharge and use of treated water

The last stage is discharging the treated water. Practical solutions vary by site:

• infiltration / drainage (if soil conditions allow),
• open water bodies,
• stormwater systems.

In some cases treated water is used for technical purposes (e.g. for watering the garden), but the safety of the specific solution and local conditions must always be assessed. (It is not drinking water.)

What can and can’t go into a biological plant?

Biological treatment is stable when only “household wastewater” goes down the drain, not waste.

Not allowed / not recommended:

• wet wipes, hygiene products, plastic, textiles,
• oils and large amounts of fat (from the kitchen),
• solvents, paints, varnishes, large amounts of aggressive chemicals,
• sand, construction debris, ash, etc.

Everyday tip:

If in doubt, don’t put it down the drain. That’s the quickest way to avoid blockages and odours.

Maintaining a biological treatment plant: what does the owner need to know?

To keep the system working reliably:

• have it maintained regularly (frequency depends on the plant and its load),
• watch for signs: odours, slow drainage, warnings on the control unit (if there is one),
• don’t “shock” the system (e.g. a very large amount of chemicals or fat in one day).

Signs that service is needed sooner:

• a persistent odour appears,
• there is frequent “gurgling” or slow drainage in the house,
• the system works erratically after rain or in spring.

Why is biological treatment popular for private houses?

• Comfort: a correctly built system works reliably and without odours
• Environment: less risk to the surroundings if the discharge is chosen correctly
• Long term: with regular maintenance and correct use, the system lasts a long time
• Fewer “surprises”: compared with solutions that need frequent emptying

Decentralised sewerage is a private wastewater collection and/or treatment system that is not connected to the central sewer. Such solutions are common in private houses, summer cottages and places where a network connection is unavailable or too expensive.

Since 31 December 2021, registering a decentralised sewerage system has become an obligation for many properties. In some cases (for example, in rural areas and on farmsteads) there may be exceptions or nuances – always check your municipality’s binding regulations.

In this article, briefly and clearly:

• what must be registered,
• how registration works,
• where to find your municipality’s form,
• and what can happen if you don’t register.

What must be registered?

The simple rule: any private sewerage system must be registered, regardless of its type or size. This applies to:

Important: if there are several systems on one property, each must be registered separately (a separate application for each).

Step by step: how to register a decentralised sewerage system

1. Identify the type of system (holding tank, septic tank, biological plant, etc.).
2. Prepare the property details (address, cadastral number – if the municipality requires it).
3. Find your municipality’s application procedure (links below).
4. Submit the application (usually by email, via an e-service or in person – depending on the municipality).
5. Keep a copy of the application and the documents relating to the system (in case clarification is requested later).

Tip: if you are not sure exactly what you have installed (a septic tank or a biological plant), it is better to find out before applying.

What you usually need to prepare (to speed up registration)

The specific requirements differ, but these are most often useful:

• the property address (and/or cadastral number),
• the system type (holding tank/septic tank/biological plant),
• its location on the property,
• installation documents / technical information (certification),
• inspection or maintenance information.

Where and how do you register?

Registration is done with the municipality where the property is located. The municipality keeps the register of decentralised sewerage systems and handles their records and inspection.

VARAM has reported that registers of decentralised sewerage systems have been set up in all municipalities, so if you can’t find the form straight away, search your municipality’s website for the keywords:

“decentralizētā kanalizācija reģistrācija” (decentralised sewerage registration) or “DKS reģistrs” (DKS register).

Municipality links (where to start looking)

• Riga
• Ropaži
• Mārupe
• Salaspils
• Ikšķile
• Ogre / Lielvārde
• Aizkraukle
• Jēkabpils
• Preiļi
• Daugavpils
• Līvāni
• Jūrmala
• Olaine
• Tukums
• Ķekava
• Ādaži
• Saulkrasti
• Jelgava
• Kandava
• Sigulda
• Cēsis
• Valmiera
• Kuldīga
• Carnikava
• Madona
• Smiltene
• Ventspils
• Liepāja

What happens if the system is not registered?

From 1 January 2022, the municipality may impose an administrative fine for not registering (in line with municipal regulations). The maximum fine can reach:

• up to €500 for individuals,
• up to €1500 for legal entities.

A biological wastewater treatment plant is one of the most practical solutions for a private house: it works reliably, reduces the risk of odours and helps manage household sewage safely. But the end result depends not only on the plant itself, but above all on correct installation and discharge of the treated water.

In this article we explain clearly how biological wastewater treatment plants are installed for private houses, how long it takes, what affects the cost and what to prepare before installation.

Installing a biological treatment plant: why does installation matter so much?

Even a good plant may not work optimally if:

• the location on site is not chosen correctly,
• the discharge solution (infiltration/ditch/pumping) is not planned,
• the connections or gradients are wrong,
• there is no access for maintenance.

So the goal is not just to “bury a plant”, but to build a system that works reliably in the long term.

6 steps to installing a biological treatment plant correctly for a private house

1) Consultation and choice of the most suitable model

We determine the capacity (number of people, intensity of use, seasonal/permanent living) and choose a suitable plant.

2) Assessment of site conditions

It is very important to assess:

• the soil type and infiltration options,
• the groundwater level,
• the terrain,
• the options for discharging treated water,

3) Earthworks and base preparation

The pit, base and position are prepared to ensure the plant is stable and works correctly.

4) Installing the plant and making the connections

The plant is installed and connected to the house sewer, and the treated-water discharge solution is planned and built.

5) Filling, adjustment and commissioning

The plant is filled, adjusted and its operation tested. The customer is shown how to use it correctly.

6) Maintenance and service

To keep the treatment quality stable and avoid faults, regular maintenance must be planned for the plant.

Correct installation of a biological wastewater treatment plant for a private house reduces the risk of odours and overflows and ensures stable treatment quality.

Note: in many municipalities, decentralised sewerage systems must be registered. The Ministry of Smart Administration and Regional Development (VARAM) reports that registers of decentralised sewerage systems have been set up in all municipalities – read more here.

Where and how should treated wastewater be discharged?

Discharging treated water is one of the most common questions. Typical solutions:

• infiltration / drainage (if the soil and conditions allow),
• discharge to a ditch / drainage system (if this is permitted at the specific location),
• pumped solutions, if the terrain requires it (no natural fall, or the discharge point is higher).

Important: choose the discharge method based on the site conditions, not “the same as the neighbours”.

How long does installation take?

The timeline depends on the amount of earthworks and the discharge solution. On simpler sites, installation can often be done quickly, but on more complex ones (high groundwater, dolomite, pumping, long pipe runs) it can take longer. Installation usually takes 1 day.

What affects the installation cost?

The main factors that make up the price are usually:

• the distance from the house to the plant (pipe run length),
• soil conditions (clay, sand, dolomite, high groundwater),
• whether a pumping station or extra components are needed,
• the treated-water discharge solution,

Tip: the cheapest solution at the start is not always the cheapest in the long run if the discharge then has to be fixed or overflows dealt with.

What to prepare before installation (to keep it quick)

Before installation, it helps to have:

• the number of people in the household,
• information about the soil/groundwater (if known),
• a rough idea of where you want the plant (or a location we can assess together),
• information about the existing system (if there is one).

The most common mistakes to avoid

• choosing a plant without a discharge plan,
• installing the plant where there is no access for maintenance,
• saving on the quality of earthworks (base, backfill, gradients),
• wet wipes, oils and aggressive chemicals ending up in the sewer (this damages the system),
• putting off maintenance “until it starts to smell”.

Eco-friendly wastewater treatment is not a compromise between comfort and responsibility towards nature – it is a modern, safe and cost-effective long-term choice for a private house, summer cottage or business property. AUGUST biological wastewater treatment plants can achieve up to 98% wastewater treatment, significantly reducing the risk to groundwater and the environment.

Biological wastewater treatment – why is it eco-friendly?

Biological treatment uses a natural process: microorganisms break down pollutants, turning them into a safer form. As a result:

• pollution of the environment is reduced,
• there are no unpleasant odours,
• treated water can be discharged in line with requirements or reused (e.g. for watering the garden, if the specific solution allows it).

What does a biological wastewater treatment plant treat?

The plant is designed to treat household wastewater, for example from:

• the toilet,
• shower and bath,
• sinks,
• washing machine,
• dishwasher.

This means all everyday sewage is treated in one place, and the property doesn’t need complicated or outdated alternatives.

Advantages of AUGUST plants (valued by homeowners)

Low power consumption

The AUGUST system runs economically, on average about ~0.8 kWh per day (depending on the model and load). That means lower monthly running costs.

High treatment efficiency

With correct installation and operation, a treatment level of up to 98% can be achieved.

Price and long-term value

Plant prices start at ~€1650 (the exact price depends on the model and project conditions). In the long run this is often better value than solutions with higher risk, more frequent emptying and extra construction.

Full service in one place

We cover the whole cycle:

• consultation and model selection,
• installation,
• commissioning,
• regular maintenance and service.

How does a biological wastewater treatment plant work?

In simple terms, the process looks like this:

1. Wastewater enters the plant, where heavy particles are separated and the flow is equalised.
2. In the aeration zone, with oxygen supplied, microorganisms actively break down the pollutants.
3. Settling takes place, where the biological mass separates from the water.
4. The treated water is discharged safely, according to the chosen solution.

Where can treated wastewater be discharged?

Treated water can be:

• discharged to infiltration / drainage (depending on soil conditions),
• discharged to a ditch / drainage system, if this can be approved and is permitted,
• in certain cases used for landscaping (depending on the solution and requirements).

Important: the right discharge method depends on the soil, the groundwater level and the specific situation, so we choose it together with the customer after an assessment.

Who is this solution suitable for?

Eco-friendly wastewater treatment with an AUGUST plant is suitable for:

• private houses and new builds,
• summer cottages,
• houses lived in permanently or seasonally,
• properties where ecology and lower running costs matter,
• places where the safety of groundwater and the environment must be considered.

Installation: how does the process work?

The process usually looks like this:

1. Consultation and choice of a suitable model
2. Assessment of site conditions (soil, terrain, access, discharge)
3. Installation and connections
4. Commissioning and basic training on use
5. Scheduled maintenance (so the system works reliably for years)

Maintenance and correct operation

To keep the plant working efficiently in the long term:

• have it maintained according to the recommended schedule,
• avoid large amounts of aggressive chemicals,
• don’t put things in the sewer that don’t belong there (wet wipes, oils, construction debris, etc.).

We can also provide regular maintenance, so you don’t have to think about it.

Today a sewerage system is not just a “pit” where all household wastewater goes. If you are a new homeowner or planning to build, sewerage for a private house is one of those things it pays to get right the first time. The wrong choice can lead to unpleasant odours, groundwater pollution and heavy fines from state authorities.
Choosing the right sewerage system for your property means:

• lower day-to-day costs,
• stable operation without odours or overflows,
• compliance with requirements and safety for the environment.

In this article we compare the 3 most popular solutions to help you decide which sewerage solution to choose for your property: a biological wastewater treatment plant, a septic tank and a holding tank.

1) Biological wastewater treatment plant

A biological treatment plant is one of the most efficient and eco-friendly solutions. It combines mechanical and biological treatment and handles household wastewater from the toilet, bath/shower, sinks, washing machine and dishwasher.

As a result, the treated water may be suitable for safe discharge or (depending on the solution) for use, e.g. for landscaping/watering.

Pros:

• high treatment quality and lower risk to the environment
• less need for frequent pumping out
• good everyday comfort (if correctly installed and maintained)

Cons:

• needs electricity and regular maintenance (service)
• the right discharge solution for treated water must be chosen

2) Holding tank

A holding tank is the simplest solution: it stores wastewater but does not treat it.

To avoid the risk of overflows and odours, it needs regular emptying, which depending on the tank volume and the region you live in can cost as much as 100 EUR a month.

Pros:

• a simple system (fewer components)
• can be suitable where discharge/infiltration is not possible

Cons:

• regular emptying costs (frequency depends on the volume and number of residents)
• a higher risk of “surprises” if emptying is delayed

3) Septic tank

A septic tank is a common solution for private houses. It stores wastewater and partially treats it by separating the fractions (liquid/solids).

For safe discharge, a septic tank usually needs additional post-treatment/filtration (e.g. infiltration in suitable conditions).

Pros:

• a simpler system than a biological plant (usually no electricity)
• can be a good solution if the soil conditions suit post-treatment

Cons:

• treatment quality is usually lower than with a biological plant
• often needs a filtration/infiltration solution, which doesn’t work equally well everywhere

To work out which sewerage system to choose, it’s important to compare not only the price but also maintenance, discharge and long-term costs.

Which sewerage system to choose: 6 questions that point you in the right direction

Answer these questions for yourself:

1. How many people will use the system? (2, 4, 6+; permanently or seasonally)
2. Is there high groundwater / poor infiltration / dolomite?
3. Is there a ditch/land drainage nearby, and can a discharge be built?
4. Do you want minimal day-to-day hassle (risk of odours/pumping out)?
5. Is electricity available, and are you ready for annual maintenance?
6. What is your long-term budget (not just for installation but also upkeep)?

Simple rules of thumb:

• If you want the best quality and comfort → a biological plant often wins.
• If you want simply to store and empty regularly → a holding tank.
• If conditions allow post-treatment and you want a system without electricity → a septic tank.

The most common mistakes that cost the most later

• choosing a solution “on price” without considering the soil conditions
• not planning the discharge (or post-treatment) of treated water from the start
• not planning access for emptying (holding tank/septic tank)
• putting off maintenance (of a biological plant) until odours or errors appear

If you are still not sure which sewerage system to choose for your property, fill in a request and we will recommend the safest solution for your property based on the soil and how you use it.

If there is dolomite (or another dense rock layer) under the soil on your property, building a sewerage solution needs a more precise approach than in “standard” situations. Not because a biological plant can’t be installed over dolomite – usually it can. The main question is how to discharge the treated wastewater correctly and safely when the ground doesn’t absorb water like sand or gravel.

In this article you will learn:

• why dolomite affects discharge,
• which solutions usually work,
• which mistakes to avoid,
• and you will see a real example from one of our installations, where the dolomite was only ~70 cm deep.

Treatment plant over dolomite: the 3 main risks

Dolomite is a dense rock layer that in some places lies close to the surface. A treatment plant over dolomite needs a slightly different approach than in “normal” soil, because dolomite affects both the excavation and the discharge of treated water.

The practical challenges:

• limited infiltration – water doesn’t disappear into the ground as easily;
• an infiltration field may not work as intended if there isn’t a sufficient filtering layer;
• there is a greater risk that water will collect or run over the surface if the discharge is not built correctly.

So when planning a biological wastewater treatment plant over dolomite, it is important to assess not only the plant model but also the discharge solution and site conditions.

Which solutions usually work over dolomite?

The specific solution depends on the terrain, groundwater, dolomite depth and whether there is a ditch/land drainage on site. Most often the choice is between these options:

1) Discharge to a ditch or an existing drainage system (if permitted)

On some sites, treated water can be discharged to a ditch or drainage system. The specific municipality and project conditions always have to be taken into account.

2) Infiltration with a prepared filtering layer (mound / “cushion”)

If the dolomite is close to the surface, infiltration is often solved with a mound and a suitable filtering layer (e.g. sand), so that the water can disperse in the intended zone.

3) A pumping station / pumped solution (if the terrain requires it)

If there is no natural fall or the discharge point is higher, pumped solutions are used to ensure a steady flow and correct discharge.

In practice: dolomite is not a “stop sign”. It simply means choosing the right way to discharge the wastewater.

A real installation example: dolomite only ~70 cm deep

On one site, the earthworks revealed dolomite at a depth of about 70 cm. We needed to install a biological wastewater treatment plant over dolomite. In such a case a standard infiltration field may not be the safest solution without additional construction, because the filtering layer may be too thin.

What we did:

• built a mound to provide a suitable filtering zone;
• installed a pumping station before the treatment plant to ensure correct flow control and operation in these conditions;
• backfilled the treatment plant with sand, which helps create a more stable and predictable environment around the plant.

When choosing a solution, it is important to assess the soil layers and plan the discharge so that the treatment plant over dolomite works reliably after rain and in spring too.

The 5 most common mistakes on sites over dolomite

1. Choosing a “standard” infiltration field without assessing the dolomite depth.
2. Not taking into account the terrain and water movement in spring / after rain.
3. Not being clear where the treated water ends up in the long term (not just “everything is fine today”).
4. Saving on construction quality and materials, and then paying twice.
5. Planning the plant but not the maintenance/service (which later causes odours and erratic operation).

If dolomite is close to the surface on your property, that doesn’t mean a biological wastewater treatment plant over dolomite is impossible – the safest start is a short assessment and a discharge plan. We will help you choose the most suitable solution and provide installation and service across Latvia.

A biological wastewater treatment plant is a reliable and eco-friendly solution for a private house, but to keep it working smoothly, what matters most is regular maintenance and correct everyday use. In this article we explain briefly and clearly how often a biological wastewater treatment plant needs maintenance, what it includes and what must not go down the drain.

How often does a biological wastewater treatment plant need maintenance?

Biological treatment plant maintenance is usually planned once a year. The exact frequency may vary depending on the plant model and its load (how many people live in the house, whether the property is used seasonally, how intensive the use is).

Tip: if the property has “peak” loads (guests, parties, seasonal living), schedule maintenance in good time to avoid problems.

What does professional maintenance include?

To keep the plant working efficiently and extend its life, maintenance usually includes the following work:

• pumping out and disposing of excess sludge
• rinsing the plant
• refilling the plant with water
• adjusting the plant
• cleaning the air compressor filter
• if needed: rinsing the sewage pumping station (if there is one)

What you can check yourself (quick checklist)

It’s worth doing a simple visual check from time to time to spot problems early:

• is there an unpleasant odour (especially near the plant lid)?
• is water draining slowly in the house / “gurgling” in the traps?
• are there visible signs of clogging?
• if there is a control unit — are there any warnings or error indications?
• is the lid secure, with no debris or surface water getting in?

Signs that maintenance/service is needed sooner

Contact the service team if you notice any of these signs:

• a smell appears that wasn’t there before
• the drains start to empty more slowly or often back up
• the control unit shows repeated warnings
• the plant makes unusual noises or its operation visibly changes
• you suspect clogging or insufficient aeration

The sooner a problem is spotted, the easier and cheaper it usually is to fix.

What must not (and should not) go into a biological plant?

Biological treatment relies on the work of microorganisms, so some substances can disrupt the process and cause odours or faults.

Do not / avoid discharging:

• large amounts of aggressive chemicals (solvents, acids, paints, varnishes, etc.)
• wet wipes, hygiene products, plastic and other items that don’t dissolve in water
• large amounts of oil and fat, food waste
• construction waste, sand, dust and the like
• water used to wash a pet (best not poured into the sewer)

A simple rule: only household wastewater should go down the drain – not waste or strong chemicals.

How does correct use reduce the maintenance risks of a biological wastewater treatment plant?

To keep maintenance a “routine” rather than an emergency, three things are enough:

1. don’t pour insoluble items or oils down the drain,
2. don’t overdo aggressive chemicals,
3. schedule professional maintenance once a year.

This helps keep the treatment quality stable and extends the life of the plant.