Industrial wastewater is one of the biggest environmental challenges of modern age. With the growth and development of industry around the world, the pressure on our water resources and ecosystems is also increasing. These waters, as a by-product of industrial processes, often contain harmful substances such as chemicals, heavy metals and organic substances, which can have serious consequences for the environment and human health. Effective pretreatment and purification of industrial wastewater, before entering the public sewage system or into recipients, is no longer only an environmental responsibility, but also a legal obligation of all industrial and public entities. Strict legal regulations set clear limits on emissions and pollution, protecting water resources and ecosystems. Thanks to modern technological treatments, the efficiency of the WWTP of the town of Kruševac, which includes physical, chemical and biological purification of waste water with activated sludge and anaerobic digestion, is increasing. purification of effluents and thus the recipient of Zapadna Morava river.