A large chemical complex like BASF AG in Ludwigshafen has a high demand of process and cooling water. Therefore, water protection and wastewater treatment are predominant tasks. With the help of a dual sewage system for the separate discharge of cooling water and process water an efficient wastewater management is made possible. The cooling water is continuously supervised for contaminations and directly discharged into the river Rhine whereas the process water is treated in a central wastewater treatment plant. The daily amount of wastewater treated is up to 600,000 m3. The BOD5 removal is about 98% and the TOC and COD removal about 88%. As wastewater management is closely connected to waste minimization several examples for waste minimization processes are discussed. Furthermore, also important topics of environmental safety of the products produced at BASF AG are presented.