ISO 24511:2007

ISO 24511:2007 provides guidelines for the management of wastewater utilities and for the assessment of wastewater services.
ISO 24511:2007 is applicable to publicly and privately owned and operated wastewater utilities, but does not favour any particular ownership or operational model.
ISO 24511:2007 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 ISO 24511:2007:

       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.