Call our friendly team for help and advise on 01388 537 050

The Best Sewage Treatment Systems of 2024

The cost of running a sewage treatment system in 2024 is dependent on the size of the system, and how it is powered. Every sewage treatment system that we supply requires some form of electricity and will require periodic servicing and de-sludging to ensure everything is operating correctly.

Electric Cost

Aeration Sewage Plant Electric Cost


A sewage treatment plant that uses an air blower to treat wastewater should run 24/7/365. The amount of energy consumed will depend on the size of the air blower. As a guidance, typical aeration systems have the following costs based on the 2024 UK average 29.0p/kWh (pence per kilowatt hour) compared to 34.0p/kWh in 2023.



PopulationBlower (W)Daily kWhAnnual kWhGB Annual £
Up to 6person501.2438£127.02
Up to 10person952.28832.2£241.34
Up to 15person1152.761007.4£292.14
Up to 20person1804.321576.8£457.27

Klargester BioDisc Sewage Plant Electric Cost


The Klargester BioDisc also runs 24/7/365. However, electric usage is calculated based on the motor & gearbox which constantly runs, turning the rotating biological contactor which treats and removes pollutants from your wastewater.



ModelMotor (W)Daily kWhAnnual kWhGB Annual £
BA BioDisc601.4525.6£152.42
BA-X BioDisc601.4525.6£152.42
BB BioDisc601.4525.6£152.42
BC BioDisc1734.11515.5£439.50

NB 1: Assumption that the blower or motor is operating at full load. Although it is appreciated this is not the situation on all sites, it is the only consistent way of comparing like for like, as each site condition would bring a varied current draw on energy usage.


NB 2: Electric costs per kWh are based on a UK average at the point in time of 29.0/kWh (estimated 2024).


NB 3: Energy consumption does not include cost for running IPS or pumped outlet systems. This would need to be measured on a flow meter as energy consumption is differs dramatically depending on site conditions.


De-Sludging Cost

Emptying is one of the biggest expenses of running a Sewage Treatment System. The emptying, also called 'de-sludging', by a tanker can start at around £195 per minimum of 1000 gallons removed by a licensed contractor. 


It is important to note - Do not let a non-licensed person empty your plant - it is illegal and heavy fines can be imposed.


We recommend the below de-sludging cycles for each system based on the manufacturers guidance. If your system is not on the list give us a call on 01388 537 050 and we can advise costs.


ModelPEDe-Sludging    IntervalsAnnual Gallons RemovedGB Annual £
BA612 Monthly600-800£195.00
BA-X912 Monthly600-800£195.00
BB1212 Monthly600-800£195.00
BC1812 Monthly1200-1500£293.00
BioFicient 1612 Monthly600-800£195.00
BioFicient 31012 Monthly800-1000£195.00
BioTec 1612 Monthly700£195.00
BioTec 212Every 6 Months700£195.00
BioTec 318Every 6 Months1000-1200£234.00
BioTec 425Every 6 Months1000-1200£234.00

Maintenance Cost

All sewage treatment plants require regular maintenance. Most domestic systems only require annual service visits which can start at around £180 +VAT and will depend on the size of your system and your location. It is worth noting that having a servicing contract with an accredited company such as RA Dalton will be the most economical method of keeping your system in line with your manufacturers warranty and compliance with the environment agency's general binding rules. If you do not have a service contract in place, you can expect your first engineers visit to cost anywhere from £200 +VAT as it is outside of their pre-planned preventative maintenance schedule. Once you have a plan in place with a provider the price will usually go down.


Larger systems can need much more frequent servicing. If you have an environmental permit to discharge, in order to comply with your permit you must take out the maintenance plan. You will also require a service plan in place with an authorised service provider to receive warranty on most systems. Unfortunately, electrical and mechanical parts can fail on sewage treatment systems. If this happens Direct drainage is here for you! We offer the a price match guarantee on all sewage treatment spare parts so you can be confident you are getting the best deal. We would highly recommend using a trusted maintenance provider such as RA Dalton Ltd to carry out regular maintenance.


To discuss servicing plans give our friendly team a call on 01388 537 050.


We also supply all spare parts for sewage treatment systems for individuals which can be fit by a suitable person.



Which is the most energy efficient sewage treatment system?


For domestic applications (Up to 25 people) the Klargester BioFicient and BioTec are considered some of the most economical sewage treatment systems on the market. For larger/ commercial applications the Klargester BioDisc model has been proven to have significantly lower running and maintenance costs than other systems

No.1 for Domestic Running Costs


For domestic dwellings without access to mains drainage, the Klargester BioTec BTA1 provides quality, reliability and peace of mind and is one of the most popular systems from this leading UK manufacturer, making it our No. 1 choice of Sewage Treatment System.

No.1 for Multiple Dwellings


For multiple dwellings without access to mains drainage, the Klargester BioDisc provides long lasting wearable parts and is proven to be more cost effective in the long run than an aeration system.

Sale Off
Klargester BioAir 2 Sewage Treatment System (up to 6 person)
£2,944.00£2,203.00
Sale Off
Klargester BioFicient 1 (No Longer Available)
£2,944.00£0.00
Sale Off
Clearwater BioTec BTA1 (No Longer Available)
£0.00£0.00