The discharge of waste water from industrial facilities or trade is subject to legal requirements. As early as 1976, binding minimum requirements were introduced nationwide with regard to treating waste water and preventing its production. These requirements have been adapted in line with technological progress over the years. In practice, this means a permit to discharge waste water can only be granted if the pollution load is as low as possible, the benchmark being the state of the art of the relevant technological process. This is stipulated in the Federal Water Act (Wasserhaushaltsgesetz, WHG).
The specific legal requirements are laid down in the Waste Water Ordinance (Abwasserverordnung, AbwV). The ordinance regulates the discharge of waste water from municipalities and 53 branches of industry, ranging from food, chemicals, iron, steel and metal processing to textile processing and finishing.
Since the adoption of the Industrial Emissions Directive (2010/75/EU), emission standards and general requirements for various branches of industry have been established and agreed in what are known as best available techniques or BAT conclusions with a view to defining the state of the art at EU level. The waste water-related requirements laid down in the BAT conclusions were transposed into German law via an amendment of the relevant annex to the Waste Water Ordinance.
The BAT conclusions for glass manufacturing and iron and steel production were transposed in 2014; those for the tanning of hides and skins and production of chlor-alkali were transposed in 2016. Transposing BAT conclusions for the production of pulp, paper and board and for refineries will be the next step.