Generally, the Topas WWTP can be temporarily overloaded up to double its designed capacity, both in terms of substance and hydraulics, for about 14 days. Activated sludge can bind pollutants into its cells and consume them later. In terms of hydraulics, the WWTP can handle more than double the flow. Prolonged overloading may lead to accumulation of pollutants in the activation volume, reducing dissolved oxygen and creating anoxic to anaerobic conditions. This can cause the complete die-off of activated sludge in the WWTP and collapse of the biological cleaning process. In such a case, it is usually necessary to evacuate the WWTP's contents and re-seed with new sludge.

No, never.

Yes, it can. It is an aerobic biological wastewater treatment plant (WWTP) that is automatically adapted for reduced inflow of wastewater to maintain its biological function for as long as possible (by limiting aeration and supplementing substrates for microorganisms from the accumulation tank). The TOPAS S type WWTPs were tested for operational maintenance after 3 and 6 months of interrupted inflow. The testing was conducted by the Engineering Testing Institute Brno (SZÚ Brno). We initiated this testing based on the requirements of our Swedish and later Norwegian significant buyers of our domestic treatment plants, as required by local water authorities. Therefore, we had TOPAS S 7 and TOPAS S 10 WWTPs, supplemented with a sand filter and phosphorus removal dosing, which we commonly supply to these markets under the trade name TOPAS Plus (i.e., plus dosing), tested. The WWTPs were installed in the standard way and then completely cut off from the inflow. At one plant, the inflow was resumed after 3 months and at the other, after 6 months of interruption. Six samples were taken from both plants over 10 days after inflow resumption. The cleaning efficiency results were virtually the same in both cases. The outflow concentrations of treated wastewater from the WWTPs were within the limits required by national legislation for the given WWTP size in all six samples taken during the first 10 days after resumption of inflow. The average efficiencies achieved in the first 10 days were close to those achieved during CE certification. For this capability, tested by the testing institute, the TOPAS WWTP was awarded the Grand Prix at the international trade fair For Arch 2018 in Prague.
A properly functioning wastewater treatment plant does not emit odors. If there is an odor, it indicates anaerobic conditions in some part of the plant which should not normally occur as all compartments of the plant should be sufficiently aerated. In such a case, it's necessary to identify the malfunction or the cause of the oxygen deficiency in the specific smelly compartment. Therefore, the plant should never smell like a septic tank or cesspit. However, it's important to remember that the wastewater treatment plant accumulates wastewater which can have an inherent odor.
If everything is prepared, meaning the pit is excavated, a gravel-sand base is ready, machinery is available for lowering the WWTP into the pit and the inlet pipe, electricity, and water for testing are provided, then the installation itself usually takes from 2 to about 4 hours.
The noise level of the blower is guaranteed by the manufacturer at 38 dB. This value meets all sanitary standards for installation next to residential buildings. However, our installation under the WWTP cover reduces the overall noise level to barely audible. With the lid closed, the sound of water splashing is more noticeable than the operation of the WWTP itself. All Topas WWTPs meet noise limits. The basic limits for outdoor noise in residential areas are 50 dB during the day (6 am-10 pm) and 40 dB at night (10 pm-6 am).
The membranes in the blower should be changed approximately every two years of the blower's operation. If the membranes in the blower are not replaced the risk of them bursting and potentially causing serious damage to the blower increases.
A wastewater treatment plant is much less infectious than a septic tank. This is due to, firstly, the principle of smaller volumes of wastewater and smaller dimensions of the facility itself, and mainly due to the different processes occurring in both systems. In a septic tank, anaerobic processes take place, resulting in biomass, water and biogas composed mainly of methane and hydrogen sulfide, which are toxic gases and hydrogen sulfide also has a strong odor. Additionally, anaerobic processes minimally remove pathogenic microorganisms that can cause infectious diseases. In contrast, in an aerobic wastewater treatment plant, oxidation of water and all substances contained in it leads to their purification and simultaneous disinfection. It has been proven that 99% of all pathogenic microorganisms in raw wastewater are eliminated during the aerobic cleaning process in wastewater treatment plants due to oxidation. The final products of aerobic wastewater treatment, in addition to biomass are water and carbon dioxide, which are harmless and odorless gases. Furthermore, the system can be equipped with chlorine disinfection or a UV lamp for additional disinfection of the treated wastewater.
Technically, it is possible but in practice it brings more complications than it seems at first glance. In most cases, neither the dimensions nor the material and construction of the original septic tank or cesspit are known. Then it is difficult to calculate the work associated with installing the WWTP in the existing tank. Therefore, we have found that the approach of installing the WWTP next to the existing cesspit or septic tank and then using it for the accumulation of treated water works well.
  • Almost noiseless operation.
  • Long-term durability.
  • Non-corroding plastic parts of the plant.
  • Tested according to EN 12566-3 (CE mark).
  • Low price (when considering all additional costs of standard plants).
  • Biological treatment.
The water is absolutely clear, clean, odourless and without turbidity. It should be indistinguishable from utility water. Often, the water at the outlet of the wastewater treatment plant is cleaner than the water in the streams into which it is discharged.
If proper maintenance is not performed on the wastewater treatment plant, the first issue to occur will be over-sludging. This manifests as an increase in the concentration of activated sludge in the activation process beyond the optimum (3-4 kg/m3, which corresponds to about 30% of the volume of the sample taken after settling for 30 minutes). As a result, activated sludge will eventually start to escape into the outflow, typically occurring when the sludge concentration exceeds about 60-70%.

60 grams

BOD 5 - The Biochemical Oxygen Demand (BOD5) is a biological indicator of water pollution, specifically measuring the amount of oxygen consumed by microorganisms during the decomposition of organic matter over a period of 5 days. The average BOD5 value for household wastewater is typically around 300–400 mg/l, while for treated water, it is usually less than 30 mg/l.

PE - The Person Equivalent (PE) is a unit representing the pollution generated by one person, with an average wastewater production of about 150 litres/day and a BOD5 production of 60 grams/day.

The Topas S 5 WWTP’s main energy consumer is a blower with a power input of about 60 W. Therefore, daily electricity consumption is 24 x 60 = 1.44 kWh/day, which amounts to 525.6 kWh/year. However, this is calculated if the blower works continuously all day/year. The Topas WWTP continuously measures wastewater quantity and automatically reduces air in the WWTP based on the amount of wastewater, leading to substantial energy savings without any maintenance. Therefore, real electricity consumption is much lower, as shown in the following table:
5 people1,4 kWh/ day1,2 kWh/day1,4 kWh/ day
3-4 people1,4 kWh/ day0,9 kWh/day1,1 kWh/day
1-2 people1,4 kWh/ day0,58 kWh/day0,8 kWh/day
0 people1,4 kWh/ day0,11 kWh/day0,14 kWh/day
As with any other equipment the lifespan of individual parts of the WWTP varies. The main part of the WWTP, i.e., the actual plastic tank, including the roof and lid must meet a minimum lifespan of 25 years under the most unfavorable conditions to obtain the CE mark. In most cases, the lifespan will be even longer, typically 30, 35, or more years. The oldest plastic WWTPs of similar construction were produced before 1989 and are still in the ground.
  • In addition to the main structure, the WWTP consists of internal technology, which is usually plastic pipes, nozzles, and hoses that harden and become brittle over time. The lifespan of these components is about 10 years, after which all the technology can be quickly and easily replaced.
  • The aeration plastic membranes, which supply air to the water in the form of fine bubbles, have a shorter lifespan within the internal technology. The lifespan declared by the manufacturer is 10 years and they can be easily replaced.
  • Other mechanical components in the WWTP are electromagnetic membrane blowers and air solenoid valves. The lifespan of both the blower and valves is considered to be 8 years, although they often function for up to 15 years in practice.
  • Regular service of the blower should be accounted for, involving the replacement of coils every 4 years and membranes every 2 years.
The user can see what water is in the tank because he is watering with it and is therefore really interested in having everything in order, in having clean water in the tank and having it available even in the dry summer months. So, this changes the overall view of users on wastewater treatment. From a facility that is a necessary evil to rid you of something bothersome - sewage - it becomes a facility that produces something valuable and desirable for you, i.e. water for watering.

For the Czech Republic and Central Europe, the standardized consumption is 150 liters. A hygienic minimum of 100 liters per person per day is considered. Actual consumption, especially in smaller municipalities, can be as low as 80 liters per person per day – or even less! Higher consumption (over 200 l/day) is typically considered for treatment plants in England, Italy, Russia, and the highest consumption of up to 280 l/day is in the USA and Canada.

PE - The Person Equivalent (PE) is a unit representing the pollution generated by one person, with an average wastewater production of about 150 litres/day and a BOD5 production of 60 grams/day.

Simply put, regular maintenance consists of an occasional visual check of the quality of the treated water after the lid of the WWTP is removed and then, after about 3-6 months (depending on the load), draining the sludge and cleaning the blower dust filter. Blower membranes need to be replaced every two years.
Topas WWTPs are made from polypropylene (PP). This plastic is classified among thermoplastics, meaning it can be joined by melting and welding at appropriate temperatures. The material is stable, non-toxic (the same is used for drinking water pipes) and is only degraded by UV radiation, i.e., sunlight. Since the entire WWTP is buried, aging is minimal and the lid, which is exposed to the most degradation, is made of PP material with a UV filter thus having an extended lifespan even in direct sunlight.
If the WWTP is connected to any food production or processing facility, professional kitchen or restaurant it is the owner's responsibility to pre-treat the wastewater from these operations in a grease trap.