New groundwater quality assessment guidelines released

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The sustainable management of water resources and the provision of safe water and sanitation are crucial for economic development and supporting health and education sectors, aligning with SDG6. Groundwater, vital for drinking water and sanitation, requires regular monitoring to ensure quality and availability. However, groundwater is often underreported compared to other water bodies. To address this issue, the Friends of Groundwater, a WWQA workstream, published the Guidelines for the Assessment of Groundwater Quality. IGRAC Groundwater Specialists Feifei Cao and Claudia Ruz Vargas have been the driving forces behind these guidelines, which have also been tested in Uganda, Chile, Sweden and South Korea.

In support of SDG 6.3.2

The guidelines for groundwater quality assessment are designed to align with SDG indicator 6.3.2, which aims to measure the percentage of water bodies with good ambient quality, defined as water that does not harm human health or ecosystem functioning. However, the practical implementation of this indicator faces challenges due to the diverse and complex water quality criteria affecting both human health and ecosystems, the wide variety of substances in natural waters, and the lack of comprehensive water quality standards for ecosystem protection.

Groundwater Quality Index

In this context, the guidelines make use of the existing target values from WHO’s drinking-water guidelines, aiming to assist general groundwater quality assessment at regional and national scales with an emphasis on the aspect of human health. The assessment involves the calculation of a groundwater quality index, followed by classifying the quality of the resource based on its potential risk on human health. It is worth noting that while the core focus of the guidelines is on human health, the underlying concept can also be further applied to assess groundwater quality for ecosystem protection, by adopting the parameters and target values relevant for ecosystem functioning.

How it’s done

The guidelines include four major steps, starting with the evaluation of existing groundwater monitoring networks according to their representativity. Next step is data collection and processing, followed by the selection of parameters to use for evaluation. Finally, the last step is the calculation of a groundwater quality index and classification of the groundwater quality.

Case study testing

These news assessment guidelines we tested within the context of national-scale case studies, which provided an opportunity to apply the guidelines in real-world settings and to understand how the guidelines perform in diverse environmental and hydrogeological contexts, as well as varying levels of data availability. Uganda, Chile, Sweden and South Korea have been selected as case study locations, because they exhibit varying degrees of data availability, covering situations with limited, moderate, and abundant amount of data. Also, groundwater quality varies significantly in these countries due to different hydrogeological contexts and anthropogenic factors.