Clean wastewater in rural areas through septic systems for wastewater treatment

When washwater is allowed to go untreated, it puts a strain on the environment. Septic systems for wastewater treatment are a clean solution in secluded areas, too. Following decades of discussion about central concepts for wastewater disposal in rural areas, recognition has grown in the recent past that central wastewater disposal covering a large area can hardly be realised.

Consequently, a trend has set in towards decentral wastewater treatment, which has given the development of modern and high-quality septic systems for wastewater treatment a real boost. Septic systems for wastewater treatment usually dispose of the wastewater of a single property; they are defined as septic systems in which a maximum of eight cubic metres of wastewater are treated per day, which corresponds to the wastewater produced by up to 50 inhabitants.

After use in the kitchen, bathroom and toilet, the wastewater contains organic substances, nutrients and household chemicals.

As a result, untreated wastewater represents a risk for humans, animals and waterways. Septic systems for wastewater treatment are decentralised wastewater treatment systems which treat the wastewater (black water) of the inhabitants and direct the treated wastewater into the soil or ground or into a flowing body of water.

A distinction is always made between mechanical treatment methods (pit drainage, three-chamber cesspits, collecting pits etc.) and biological treatment methods. According to the latest version of the wastewater directive (AbwV) dated 16.12.2002 , only biological methods are allowed in Germany today.

There are two different biological methods:

• Without technical wastewater aeration
• With technical wastewater aeration