User:Atsushi Tim Saito/sandbox

Share of domestic wastewater that is safely treated

Global situation

At a global level, appropriate wastewater treatment is still lacking in many countries. For this reason, Sustainable Development Goal 6 has a Target 6.3 which is formulated as follows: "By 2030, improve water quality by reducing pollution, eliminating dumping and minimizing release of hazardous chemicals and materials, halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally." The corresponding Indicator 6.3.1 is the "proportion of wastewater safely treated" (see map on the right for 2018). For example, Algeria, Senegal, Niger, Libya, Uganda, Somalia, and Iraq do not treat domestic wastewater safely yet.

Disposal or reuse

Although disposal or reuse occurs after treatment, it must be considered first. Since disposal or reuse are the objectives of wastewater treatment, disposal ,or reuse options are the basis for treatment decisions. Acceptable impurity concentrations may vary with the type of use or location of disposal. Transportation costs often make acceptable impurity concentrations dependent upon the location of disposal, but expensive treatment requirements may encourage the selection of a disposal location on the basis of impurity concentrations. Ocean disposal is subject to international treaty requirements. International treaties may also regulate disposal into rivers crossing international borders. Water bodies entirely within the jurisdiction of a single nation may be subject to regulations of multiple local governments. Acceptable impurity concentrations may vary widely among different jurisdictions for disposal of wastewater to evaporation ponds, infiltration basins, or injection wells.

European Union

Member states in the European Union maintain and operate waste-water treatment plants to conform to the Urban Waste Water Treatment Directive which sets standards for both treatment and disposal of sewage for communities of more than 200 person equivalents. Each member state is obliged to enact the requirements of the directive through appropriate local legislation. This directive also links to the Bathing Waters Directive and to the environmental standards set in the Water Framework Directive which are designed to protect all legitimate end uses of the receiving environment.