Modernization obligation for small sewage treatment plants

The year 2015 brings massive changes for small wastewater treatment plant owners. Since the beginning of the year at the latest, many small wastewater treatment plants have to be retrofitted, otherwise they may no longer be operated. What is changing for the small wastewater treatment plant operators, and what are the effects throughout Germany, summarizes this article briefly.

European Water Directive 2015

As the number suggests, the EU Water Framework Directive (2000/60 / EC) dates back to 2000. By 2015 at the latest, however, this directive provides for a good ecological status of waters.

The reason for this was the partially catastrophic conditions in many European waters at the beginning of the millennium. The directive then provided for systematic improvement over 15 years, and prevention of further deterioration of conditions.

National law in Germany

The directive is binding for all EU member states and must be transposed into national law. In Germany, the national law is the Water Resources Act (WHG). It is extended and supplemented by the Land Water Acts, which may each contain different, more extensive provisions.

Further details can be found in the individual municipalities. There are also differences there. The agreed and firmly anchored environmental objectives for the quality of surface waters and groundwater, the primary sources of drinking water, are in place of all country and local regulations.

Impact on small sewage treatment plants

Small wastewater treatment plants must therefore meet certain technical requirements. If these standards are not met, operation after 2015 is no longer permitted.

Biological treatment required

The requirements at the individual locations may vary, but they all have in common that an operating permit for small sewage treatment plants without a biological treatment stage is no longer granted. This purification step almost completely removes germs and nitrogen from the sewage.

In older small sewage treatment plants without such a purification stage, the two water-polluting contents are retained and thus also reach rivers and surface waters, which are used as receiving waters.

Financial burden on the budget

The financial burden on the budget was only mitigated in some federal states by corresponding subsidies, which were very different. In most areas, however, the homeowner had to bear all the costs himself.

The investment costs of often up to 6,000 EUR were a heavy burden for many households. In addition, the demand pressure at the end of the deadline drove up the prices for retrofitting in some areas significantly. Many homeowners were waiting with the retrofitting virtually to the last minute.

Currently around 1.7 million small sewage treatment plants are in operation in Germany, about one third of which had to be modernized. Small sewage treatment plants can be found mainly in rural areas, where a connection to the sewer system would not be worthwhile for the communities. In Saxony, for example, one plans to officially connect only about 86% of households to the sewer system. The rest must ensure efficient water quality after treatment with efficient small wastewater treatment plants, and thus take over responsibility for water protection on their own.

Video Board: Overview of Septic Systems