prBAS ISO 24511:2025

This document provides guidelines for the management of wastewater utilities and the assessment of wastewater services. This document is applicable to publicly and privately owned and operated wastewater utilities but does not favour any particular ownership or operational model. NOTE 1        Wastewater is always generated when water is used or consumed. Accordingly, sources of wastewater can be residential, industrial, commercial or institutional. Collected storm water or (melted) snow can also be considered as wastewater, as it often carries contaminants and pathogens picked up from air or ground surfaces on its way to a collection system. In certain circumstances, especially in undeveloped areas, sanitary waste is collected in an undiluted form. This document addresses wastewater systems in their entirety and is applicable to systems at any level of development (e.g. pit latrines, on-site systems, networks, treatment facilities). The following are within the scope of this document: —     the definition of a language common to different stakeholders; —     objectives for the wastewater utility; —     guidelines for the management of wastewater utilities; —     service assessment criteria and related examples of performance indicators, all without setting any target values or thresholds. The following are outside the scope of this document: —     methods of design and construction of wastewater systems; —     regulation of the management structure and the methodology of wastewater service activities of operation and management; —     regulation of the content of contracts or subcontracts; —     topics related to the systems inside buildings, between the point-of-discharge and the point-of-collection.