In the UK, septic tank regulations are due to update in 2020. These new regulations will affect those who own a property that uses a septic tank which discharges treated water to a watercourse, not a soakaway or drainage field. If this is currently how your wastewater is treated, you have until 1st January 2020 to upgrade or replace your wastewater system.

One of the easiest ways to meet these new regulations is by replacing your septic tank with a domestic sewage treatment plant. These plants produce a cleaner form of water which is considered clean enough to discharge straight to a watercourse.

One of the main problems people tend to have with changing the way they treat their wastewater is the fear of not having enough room for a alternative wastewater treatment system at their property. Fortunately, there are several types of individual wastewater treatment plants on the market that address this space problem.

Two non-collective water purification systems can be installed in a relatively small space: the compact filter and the domestic sewage treatment plant.

In our report, we will focus in particular on the small sewage treatment plant which is designed to operate on a small plot of land.

A system adapted for a minimal surface area

small-sewage-treatment-plantUnlike older septic tanks and all-water tanks, domestic sewage treatment plants use a biological degradation process to treat wastewater.

Aerobic bacteria feed on organic matter in the sewage treatment plant to purify the wastewater.

Due to it being an all-in-one solution to wastewater treatment, the domestic sewage treatment plant treats all your wastewater from A to Z. Unlike the all-water tank and thanks to its exclusive technology, this device does not require external ventilation.

It therefore does not emit gas or unpleasant odours. In fact, it is considered eco-friendly because it does not use chemicals to treat wastewater.

However, the sewage treatment plant is especially appreciated for its compactness. It only requires a footprint of less than 15 m2, whereas a traditional system including land application requires an area of 50 m2 to 100 m2 or more.

The different types of small sewage treatment plants

There are currently three types of sewage treatment plants that you can choose to treat your wastewater.

  • Fixed-film domestic sewage treatment plants: the purifying bacteria are fixed on a specific support installed in the treatment tank.
  • SBR sewage treatment plants: bacteria are also free when activated. Water treatment is alternated by phases of rest and biological reaction. This makes it possible to offer a high purification efficiency at the sewage treatment plant.

SBR models are the most expensive, followed by the domestic sewage treatment plants with fixed-film. Suspended-growth models are the cheapest, but also the least effective.

You should also know that the fixed-film technology offers almost the same purification yields as an SBR system, at a reduced price.

Regardless of the choice of your device, they all ensure that you comply with the 2020 septic tank regulations update.


Overall, the domestic sewage treatment plant is therefore the ideal wastewater treatment solution for a small area. However, you can also install one even when the land in your home is non-existent.

In fact, it is the only device that can be installed above ground. In this case, you can install it in a garage or cellar.