What are the types of water quality?
Water quality can be classified into four types—potable water, palatable water, contaminated (polluted) water, and infected water.
What are the 5 core parameters of ambient water quality?
SDG Indicator 6.3.2 monitors the proportion of bodies of water with good ambient water quality, in relation to national and/or subnational water quality standards. This is done based on measurements of five water quality parameters that provide information on the most common pressures on water quality at the global level. The five water quality parameters are:
dissolved oxygen (surface water)
electrical conductivity (surface water and groundwater)
nitrogen/nitrate (surface water and groundwater)
phosphorus (surface water)
pH (surface water and groundwater)
More information on Indicator 6.3.2 “Proportion of bodies of water with good ambient water quality” can be found here: https://www.sdg6monitoring.org/indicator-632/.
Why is water quality important?
Life on our planet is highly dependent on freshwater. Freshwater is a scarce resource and is a very small fraction of all water on the planet. While nearly 70 percent of the world is covered by water, only 2.5 percent of it is freshwater. The rest is saline seawater. Even then, just around 1.2 percent of our freshwater is easily accessible, as much of the 2.5 percent of total freshwater is trapped in glaciers and ice caps (68.7 percent) and groundwater (30.1 percent). Preserving the quality of freshwater is essential to prevent harm to human health and to the aquatic ecosystems, from which we get many other benefits such as drinking water, food and recreation.
What are the challenges in measuring water quality around the world?
There is a substantial water quality data gap at the global level, and despite decades of efforts, this gap has proved difficult to fill. SDG indicator 6.3.2 alone does not necessarily fill this gap, but it does bring together information on water quality in a consistent and reliable manner, and it also provides insight into where and how data are collected. Through engagement with countries, it helps to flag the challenges faced, such as insufficient monitoring activities or an absence of ambient water quality standards.
Furthermore, data sharing can sometimes be difficult, especially between countries. The African Use Cases for lake Victoria, Volta basin and Cape Town aquifers of the World Water Quality Alliance (WWQA) aim to address issues that may arise with sharing data in transboundary environments.
Another challenge in measuring water quality is that in-situ data on water quality often requires laboratory work, skilled technicians and adequate research infrastructure, which are not available in all countries. Capacity development, such as provided by the Global Environment Monitoring System for freshwater (GEMS/Water), or the World Water Quality Alliance (WWQA) can be targeted to counter these challenges and thereby drive further data collection.
Want to learn more about the challenges associated with water quality monitoring? Then we recommend the following recording of a session organized by the World Water Quality Alliance at the Stockholm World Water Week 2021: https://www.youtube.com/watch?v=6pnI9YFLfvo
How to overcome some of the challenges associated with a lack of in-situ water quality data?
An approach that combines different data sources from remote sensing/earth observation, modelling and in-situ data (so-called “triangulation approach”) can help to obtain a more complete picture of global water quality. However, while the triangulation approach holds potential for obtaining a more comprehensive view on water quality using different sources, especially in those areas where in-situ data is limited, there is no substitute to in-situ water quality monitoring which is required for validation of remote sensing data, and also to calibrate and provide input data to models used.
Want to learn more about the challenges associated with a lack of in-situ water quality data? Then we recommend the following recording of a session organized by the World Water Quality Alliance at the Stockholm World Water Week 2021: https://www.youtube.com/watch?v=6pnI9YFLfvo
What is the relationship between clean, good quality freshwater, and clean seas?
Only quite recently have we come to truly understand the many important linkages between land, freshwater and oceans. Generally, terrestrial, freshwater and marine specialists have tended to work independently from one another, with limited interaction. But with new insights into the complex relationship between different ecosystems – on land and in rivers, deltas, estuaries, nearshore and in oceans – comes a growing realization that a more holistic approach is needed. A source-to-sea (S2S) approach directly addresses the linkages between land, water, delta, estuary, coast, nearshore and ocean ecosystems leading to holistic natural resources management and economic development. It shows that land-based pollutants that affect freshwater bodies also have a considerable effect on marine ecosystems.
The United Nations Environment Programme (UNEP) is working on several fronts to link SDG 6 about “clean water and sanitation for all” with SDG 14 about “life below water”. A good example of this is UNEPS Global Environment Monitoring System for the Ocean and Coasts (GEMS Ocean) which is working towards incorporating Land and Sea data following a S2S approach. In that context, UNEP is exploring synergies between Integrated Water Resources Management (IWRM) and Integrated Coastal Zone Management (ICZM). UNEP has also included the often overlooked but vital mangrove ecosystems in its Ecosystems Explorer.
How is groundwater quality measured, is it different from surface water?
Groundwater can be affected by both geogenic (resulting from geological processes) and anthropogenic (resulting from human activity) pollutants, and monitoring its quality is generally more complex than monitoring surface water. Because of its immense importance, 2022 has been declared as the year of groundwater under the theme “Groundwater – making the invisible visible”
One major complexity of assessing groundwater quality arises from the 3-D nature of flow systems. Groundwater systems are often highly heterogeneous, meaning that samples from wells in close proximity may produce very different results, especially if they are taken from different depths. Well construction may also impact on the groundwater quality data: for example, two wells of identical depth may produce contrasting groundwater quality results if one of them is constructed with a grouted upper well casing and the other is not. It is therefore necessary to monitor groundwater quality at different depths using special borehole designs such as clusters, piezometer nests or using multi-level devices (Misstear et al., 2017).
Priority contaminants affecting groundwater include salinity (usually monitored as electrical conductivity, EC), acidity (pH), major ions, nitrate, microbiological pollutants, contaminants of emerging concern (CECs – pharmaceuticals, etc) and geogenic parameters, notably arsenic, iron, manganese, fluoride and radionuclides.
In 2021, the World Water Quality Alliance released a perspective paper by the Friends of Groundwater (FoG) group which aims to give a compelling argument for the importance of groundwater quality for human development and ecosystem health. The document can be found here: https://communities.unep.org/display/WWQA/UNEA-5+Resources
Which country has the freshest water?
Due to significant data gaps on water quality, both spatially and temporally, it is very difficult to assess which country in the world has the freshest water. The United Nations Environment Assembly (UNEA) at its third session in December 2017 adopted resolution 3/10 “Addressing water pollution to protect and restore water-related ecosystems” (UNEP/EA.3/Res.10) which led to the establishment of the World Water Quality Alliance (WWQA) which develops a World Water Quality Assessment for UNEA’s consideration.
How much of the world's water is polluted and what are the main sources of freshwater pollution?
Due to significant data gaps on water quality, both spatially and temporally, it is very difficult to assess the exact amount of polluted freshwater and waterbodies globally. However, the “World Water Quality Assessment: First Global Display of a Water Quality Baseline” shines a spotlight on some of the most significant sources of water pollution, how they are affecting freshwater around the world and identifies some hotspots around the world, focusing on pollution impacts to human end ecosystem health and food security. The report was developed by the World Water Quality Alliance (WWQA), in 2021 and shows that anthropogenic nutrient sources (i.e. those from human activities) contribute to more than 70% of river nutrient loading. For groundwater arsenic and surface water salinity concentrations, hotspot areas include India, China and Mongolia. Further, first estimates of water quality impacts on food security show hotspots in north-eastern China, India, the Middle East, parts of South America, Africa, Mexico, United States and the Mediterranean.
The WWQA will be releasing a World Water Quality Assessment in 2023.
To learn more: World Water Quality Assessment
What does SDG 6 measure?
Sustainable Development Goal 6 about clean water and sanitation for all (SDG 6) seeks to ensure safe drinking water and sanitation for all, focusing on the sustainable management of water resources, wastewater and ecosystems, and acknowledging the importance of an enabling environment.
More information about SDG 6 can be found here: https://www.sdg6data.org/
Why does SDG 6 matter?
Sustainable Development Goal (SDG) 6 about "clean water and sanitation for all" is a connector to many of the other SDGs. Water resource management supports many social, economic and environmental goals and contributes to the achievement of all SDGs, including good health, food security and gender equality. The diagram below shows the important role SDG 6 has in conjunction with other SDGs
Source for image: https://www.unescap.org/sites/default/files/Visualisation%20of%20interlinkages%20for%20SDG%206_new.pdf (please note: visualisation map does not provide a comprehensive overview of all interlinkages)
How many indicators does SDG 6 have?
The UN has defined 8 Targets and 11 Indicators for Sustainable Development Goal (SDG) 6 about "clean water and sanitation for all". Targets specify the goals and Indicators represent the metrics by which the world aims to track whether these Targets are achieved.
Water and water-related ecosystems play a fundamental role in the health of the environment, in providing services to people and communities, in combating the impacts of climate change and in all economic activities. Working on the environmental aspects of monitoring, managing and protecting water resources and freshwater ecosystems has been an integral part of UNEP’s mandate since its inception. Against this background and in the framework of the Sustainable Development Goals, UNEP has been entrusted with the co-custodianship of three water indicators (SDG 6.3.2, 6.5.1 and 6.6.1) related to the following freshwater targets:
SDG 6.3: 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;
SDG 6.5: By 2030, implement integrated water resources management at all levels, including through transboundary cooperation as appropriate;
SDG 6.6: By 2020, protect and restore water-related ecosystems, including mountains, forests, wetlands, rivers, aquifers and lakes. In addition, UNEP’s freshwater activities contribute to reaching and monitoring several other water-related SDG targets.
Source: https://sdg-tracker.org/water-and-sanitation
What is acceptable water quality?
Water quality criteria are developed by scientists and provide basic scientific information about the effects of water pollutants on a specific water use (see Box 2.1). They also describe water quality requirements for protecting and maintaining an individual use. Water quality criteria are normally based on variables that characterize the quality of water and/or the quality of the suspended particulate matter, the bottom sediment and the biota. Many water quality criteria set a maximum level for the concentration of a substance in a particular medium (i.e. water, sediment or biota) which will not be harmful when the specific medium is used continuously for a single, specific purpose. For some other water quality variables, such as dissolved oxygen, water quality criteria are set at the minimum acceptable concentration to ensure the maintenance of biological functions.
However, it is important to note that threshold values and targets used for determining water quality can change, even significantly, from one country or region to another. There are not always harmonized methodologies for measuring certain water quality variables, especially regarding those found in connection with pollutants of emerging concern. This can make it difficult to compare water quality across different countries and regions.
Source: https://www.who.int/water_sanitation_health/resourcesquality/wpcchap2.pdf
What determines water quality?
Water quality is naturally influenced by the climatological and geochemical location of the water body through temperature, rainfall, leaching, and runoff of elements from the Earth’s crust. However, most surface water bodies around the world are also affected to some extent by impacts from human activities, particularly the discharge of waste products (including sewage and plastics) or addition of sediments, salts and minerals with run-off from agriculture and urban settlements. There is an urgent need to better understand the current drivers and pressures affecting the quality of this vital resource and drivers of its degradation.
What is the role of capacity building in ensuring water quality?
Capacity building allows for increased generation of reliable water quality data, therefore enabling the targets of SDG 6, particularly 6.3.2, to be monitored in a consistent way. More data is needed to assess the state of freshwater bodies around the world and take action around issues of concern. This will also provide data to feed into the current and future world water quality assessments. Capacity development on freshwater monitoring, such as provided by the Global Environment Monitoring System for freshwater (GEMS/Water), or the World Water Quality Alliance (WWQA) can be targeted to counter these challenges and thereby drive further data collection. SDG 6 specific information about capacity development can be found at: https://communities.unep.org/display/sdg632/Documents+and+Materials
What are the gender dimensions around water quality?
Gender and water quality is predominantly an issue across low-income countries where primarily women and girls are responsible for the management of household water supply, sanitation and health. Therefore, addressing the needs of females in relation to water, sanitation and hygiene is a key driver in achieving gender equity and locking the potential of half of global society.
Source: https://www.unwater.org/water-facts/gender/
What is the World Water Quality Alliance and what is its role?
The World Water Quality Alliance (WWQA), represents a voluntary and flexible global multi-stakeholders network that advocates the central role of freshwater quality in achieving prosperity and sustainability; it explores and communicates water quality risks in global regional, national and local contexts with the aim of pointing towards solutions for maintaining and restoring ecosystem and human health and well-being, with an aim to serve countries throughout the lifetime of the 2030 Agenda for Sustainable Development and beyond. The WWQA aims to provide a participatory platform for water quality assessments and co-design of tailored and demand-driven services.
How to join the World Water Quality Alliance?
Send an e-mail to wwqa-coordination@un.org stating which workstream/s you would like to contribute to, a short summary of your organization and how the work your organization does links to the specific workstream/s of the WWQA.
How many workstreams does the World Water Quality Alliance have?
As of January 2022 – 14 workstreams – a summary of the workstreams can be found here
How many partners does the World Water Quality Alliance have?
More than 100 partners work together on the 14 workstreams.
When was the World Water Quality Alliance established?
The World Water Quality Alliance (WWQA) was formally launched in September 2019 in Ispra at the Joint Research Centre (JRC) of the European Commission as a co-host (see UNEP Press Release), bringing together a wide range of expertise from within the UN System, international research institutes, space agencies and Earth Observation Services, private sector and civil society.
Is the World Water Quality Alliance part of UNEP?
The WWQA is an independent voluntary community of practice that is convened by UNEP which houses its Coordination Team and supported by the Swiss Confederation.
How is the WWQA governed?
As main structures supporting the governance process of the Alliance, a Strategic Advisory Committee (SAC) and a Technical Advisory Committee (TAC) were established, each represented by 12 Alliance partners. The SAC and TAC represent two separate entities with complementary profiles and responsibilities (see Terms of Reference) that work in tandem to assist and support workstreams, guarantee impartiality and inclusivity and ensure high quality output and dissemination.
