Wastewater

Unique identifier / Notation

TL0037

Synonyms

Used water,

Effluent.

Wastewater is regarded as a combination of one or more of the following materials: domestic effluent consisting of ‘blackwater’ (excreta, urine and faecal sludge, contaminants from pharmaceutical and personal care products) and ‘greywater’ (used water from washing and bathing); water from commercial establishments and institutions, including hospitals; industrial effluent, stormwater and other urban runoff; and agricultural, horticultural and aquaculture runoff (UN Water, 2017).

Primary reference(s)

UN Water, 2017. Wastewater: The Untapped Resource. Accessed 13 November 2019.

Additional scientific description

Insufficient treatment of wastewater and faecal sludge spreads disease and is a driver of antimicrobial resistance (WHO, 2019). Wastewater is also considered to contain increasing amounts and types of unregulated contaminants and organic compounds of emerging concern, such as human and veterinary antibiotics, and prescription and non-prescription drugs (USGS, 2051).

Metrics and numeric limits

Not available.

Key relevant UN convention / multilateral treaty

Convention on the Protection and Use of Transboundary Watercourses and International Lakes also referred as the Water Convention (1992). Although initially intended for the United Nations Economic Commission for Europe (UNECE) region, in 2016 the Water Convention allowed accession of all United Nations Member States worldwide. At the time of writing, there were 43 parties to the Water Convention. Almost all countries sharing transboundary waters in the UNECE region are Parties to the Convention (UNECE, 2019).

Examples of drivers, outcomes and risk management

Industrialisation without adherence to environmental standards and lack of wastewater management systems is a driver of contaminated wastewater. Globally, approximately 80% of all wastewater is discharged without adequate treatment (UNESCO, 2017). As of 2014, most cities were missing the appropriate infrastructure and resources to address wastewater management in an efficient and sustainable way (UNDESA 2014, cited in UN Water, no date). Urban areas with high population densities in low-income and lower-middle income countries are considered particularly at risk (UNEP, 2016). Discharge of wastewater without adequate water treatment may have serious implications for health and well-being (UN Environment, 2017).

In parallel, wastewater treatment plant operatives are exposed to a variety of hazardous chemical agents, within the effluents and the reagents used in water processing, or generated during water treatment. These chemical agents may cause acute poisoning, chemical accidents (skin burns, injury to the eyes, etc.), damage to the respiratory system, allergies, dermatitis, and chronic diseases (ILO, 2012).

Demand for wastewater as a reliable source of water and nutrients for agriculture is growing under the pressures of population growth, urbanisation, increasing water scarcity and the effects of climate change (WHO, 2019).