3700Wastewater Management

operation of wastewater treatment facilities for reuse, for example for agriculture, industry, street cleaning, and artificial groundwater recharge; | collection and transport of wastewater from sources, such as households or industrial units; | collection and transport of rainwater; | wastewater treatment; | management and cleaning of waterways and sewers; | freeze-drying of sewage sludge by wastewater treatment facilities; | desludging and cleaning of cisterns, septic tanks, and pits from waste; | maintenance of chemical toilets (portable toilets, airplane toilets, train toilets).