There’s a whole fascinating world that exists underneath our feet that we don’t see, therefore we don’t relate.”  Erin Brockovich, environmental activist

The only time many people really think about groundwater is when things have gone terribly wrong— when they hear about community wells drying up or when toxic chemicals have leached into the groundwater, causing long, arduous walks to distant water supplies or cancers that appear after years of exposure.

The reaction is one of horror and sympathy. They look at the water in their glasses differently for a moment. Then they forget.

But it’s important to remember that groundwater provides half of all water used by households worldwide, a quarter of all the water drawn for irrigated agriculture, and one third of the water supply required for industry.

This year’s World Water Day aims to make groundwater more visible.

The launch of the UN World Water Development report sounds the alarm on the many current and impending threats to groundwater, exacerbated by climate change and ever-growing demand — and therefore to the health and wellbeing of billions of people — and challenges to its safe use.

But there are also solutions to these threats that deliver outsized health benefits. It’s time for the world to make good its commitment to fulfil the 2030 sustainable development goal of ensuring universal access to water, sanitation and hygiene.

Protecting groundwater

Improving sanitation management can have a profound impact on drinking-water quality from both surface and vulnerable groundwater sources, particularly when sewage or excreta contaminate drinking-water sources.

Progress on safely managed sanitation needs to accelerate at least four times (many more in some regions) and include greater focus on its impact on groundwater. Efforts must include the application of  sanitation safety planning, a risk-based approach for sanitation systems to assess, prioritize and manage public health risks along the entire sanitation chain (i.e. from toilet, containment-storage/on-site treatment, conveyance, treatment to end-use/disposal) and recommended in WHO’s Guidelines on Sanitation and Health.

It’s also vital to address threats like over-abstraction and climate change, both of which are responsible for reducing groundwater levels, and thus groundwater quality and quantity. 

Detailed guidance is available to support the management of groundwater sources used for drinking water, including water safety planning, a complementary approach to sanitation safety planning, applicable to drinking-water systems, from catchment to consumer. Water safety plans are recommended as the most effective approach to ensure the consistent delivery of a safe and acceptable drinking-water supply in WHO’s Guidelines for drinking-water quality.

It’s important to contain naturally occurring chemicals such as fluoride and arsenic, that could be harmful to health at elevated concentrations.

Excessive exposure to manganese from groundwater could be another concern. In these updated Guidelines, the manganese fact sheet has been revised with an updated risk assessment, recommended concentration limits, and expanded risk management advice. More detailed information can be found in the manganese background document for the drinking-water guidelines.

Improving sanitation

Strong government leadership and investment in resilient drinking water and sanitation services will also help protect groundwater. The WHO and UNICEF State of the World’s Sanitation report charts an ambitious way forward to achieve universal access to safe sanitation, presents case studies and highlights challenges, successes and best practices. A companion publication on drinking water will be published later this year by WHO, UNICEF and the World Bank.

Currently, 2.2 billion people have limited access to safe drinking water, and by 2025, half of the world’s population will be living in water-stressed areas.

As climate change (and its hydrological impacts) makes itself increasingly known and as population growth and increased industrialization magnify existing threats to aquifers and watersheds, it’s increasingly important to highlight the link between groundwater and health – and to take steps to protect them both.