Municipal Wastewater Directive (Directive 2024/3019)
On 1 January 2025, the revised Municipal Wastewater Directive (MWD) came into force.
After the entry into force of KARL (Directive - EU - 2024/3019 - DE - EUR-Lex), EU Member States have 30 months to transpose the new provisions into national law, i.e., to amend the relevant national laws and regulations. The adaptation of sewer systems and wastewater treatment plants to the new requirements will take place gradually until 2045.
The revision of the directive resulted in a comprehensive change of KARL. KARL was published in 1991. Its purpose is to protect the environment from the harmful effects of municipal wastewater and the wastewater of certain industrial sectors. It forms the legal framework for the organized collection and treatment of municipal wastewater throughout the European Union.
Some key changes under the new KARL are:
Lowering the scope to 1,000 population equivalents
The scope of the directive is expanded from the previous 2,000 population equivalents (PE) to municipal wastewater treatment plants from 1,000 PE.
Integrated management plans for wastewater and stormwater
By 2033, settlements with 100,000 PE, and by 2039, selected settlements with 10,000 PE, will need integrated management plans for municipal wastewater and stormwater. The plans must be updated at least every 6 years and include measures to improve the management of wastewater and stormwater, which must also be implemented. Blue-green infrastructure solutions should be given priority.
Stricter requirements for nitrogen removal
Large municipal wastewater treatment plants from 150,000 PE must achieve a removal rate of at least 80% for nitrogen by 2039. Medium-sized treatment plants from 10,000 PE have until 2045.
Stricter requirements for phosphorus removal
For large municipal treatment plants from 150,000 PE, the new KARL provides a phosphorus limit of 0.5 mg/L from 2039. For medium-sized treatment plants from 10,000 PE, 0.7 mg/L will apply from 2045.
New fourth treatment stage
Large municipal treatment plants from 150,000 PE must gradually be retrofitted with an additional treatment stage to remove a wide range of chemical trace substances by 2045. Selected medium-sized plants from 10,000 PE must also be retrofitted if they discharge into areas at risk regarding trace substances. The fourth treatment stage is financed at least 80 percent through an Extended Producer Responsibility system. In simple terms, this means that manufacturers, importers, or distributors from certain industrial sectors who place trace-substance-releasing products on the Austrian market must make a financial contribution.
Energy audits for sewer systems and wastewater treatment plants
New mandatory energy audits for sewer systems and treatment plants from 10,000 PE, as well as the goal to achieve energy neutrality at the Member State level for these treatment plants by 2045. Overall, wastewater treatment plants from 10,000 PE in Austria should no longer consume more energy than they generate. The energy for operating the plants can be generated on-site or elsewhere. Up to 35 percent of non-fossil energy can also be purchased from external providers in the final stage.
Improving access to sanitary facilities
Access to sanitary facilities should be improved. Municipalities from 5,000 PE are encouraged to provide a sufficient number of freely accessible sanitary facilities in public buildings. Municipalities from 10,000 PE must also provide these in public spaces. Cooperation with the gastronomy and retail sectors should be strengthened so that their sanitary facilities are accessible free of charge or for a small fee.