Severe flooding this year in Pakistan, Nigeria and, most recently, Chad not only destroyed crops, homes and infrastructure. It also inundated latrines, sewers and open defecation sites, funnelling pathogen-laced sludge into drinking water supplies and sparking disease outbreaks.
The effect was particularly devastating in marginalized communities — and experts say it could be a grim preview of what is to come. As the Earth’s climate changes, more intense flooding and rising sea levels threaten to overwhelm sanitation systems, especially in developing countries, many fear.
But these countries are not alone in facing such threats. Jackson, the capital of Mississippi in the United States, recently lost access to safe running water after extreme flooding.
“All countries need climate-resilient sanitation systems,” says Leticia Carvalho, head of the United Nations Environment Programme’s (UNEP’s) Marine and Freshwater Branch. “Developed countries, and the richest segment of the population in all countries, are responsible for the bulk of the climate change impacts we are seeing around the world.” She added that those most vulnerable who have done little to contribute to climate change are feeling the biggest impacts. “We urgently need more funding to foster a just transition and build resilience in all countries.”
Research shows that untreated wastewater is at the heart of the social, economic and public health problems many developing countries face and affects rivers, aquifers, coastal ecosystems, and corals globally. Around one-third of all rivers in Latin America, Africa and Asia are polluted with dangerous pathogens that cause illnesses such as diarrhoea, cholera and typhoid fever. In many countries, untreated sewage is routinely pumped into rivers or directly into the ocean.
"Developed countries also need to up their game,” says Carvalho. “The discharge of untreated sewage directly into rivers and the ocean by developed countries is a completely unacceptable environmental crime.”
Globally, 44 per cent of household wastewater is not safely treated, and an estimated 80 per cent of wastewater, including from agriculture and industry, goes untreated, polluting both fresh and saltwater bodies.
Some 3.6 billion people lack safely managed sanitation infrastructure, and at least 2 billion use a drinking water source contaminated with faeces. Meanwhile, one in three people cannot access safe drinking water. Africa is particularly at risk.
To help address these critical issues, UNEP has released a Sanitation and Wastewater Atlas of Africa to benchmark and propel Africa’s progress towards Sustainable Development Goal (SDG) targets on safe sanitation and wastewater management.
But as UN Secretary-General António Guterres said at the UN Climate Conference (COP27) this week in Sharm el-Sheikh, Egypt, much more needs to be done to compensate for the loss and damage suffered by vulnerable countries hit hardest by natural disasters.
Focus on groundwater
World Toilet Day, which falls on 19 November, and is backed by the UN, is designed to raise awareness about the lack of universal access to adequate sanitation.
This year, the day focuses on the links between sanitation and groundwater, providing 99 per cent of liquid fresh water on Earth and half of the water withdrawn for domestic use.
The day highlights the need for sanitation systems that can withstand the extreme weather caused by the climate crisis and protect groundwater sources.
In many places, severe flooding causes the faecal matter to mix with toxic chemicals, plastic and electronic waste, and other debris, creating a deadly concoction that can seep into groundwater. In South Africa for example, run-off from small-scale farms, landfills, cemeteries, factories and informal settlements risks leaching into the Cape Flats aquifer, which lies under much of Cape Town, found a recent UNEP study.
Groundwater globally is a major source of drinking water, and once contaminated it is difficult or impossible to restore.
Experts say financing the building of infrastructure to protect groundwater sources from pollution is vital and should be considered part of the UNEP-supported One Health approach, which aims to sustainably improve the health of people, animals and the wider environment. It mobilizes businesses, governments and communities to address the collective need for clean water.
Nature-based solutions can complement efforts to bolster sanitation systems. Preserving vegetated wetlands, for example, allows them to soak up excess water and counter the effects of flooding. But developed countries need to step up to the mark and provide adequate finance and capacity-building to make such solutions viable.
Many communities around the world are racing to do what they can to safeguard their sanitation systems. Some are building raised latrines and hand pumps for drinking water, which would sit above floodwaters in flood-prone areas. Others are looking to new technologies.
UNEP has supported a pilot project in Malaysia to install portable septic tanks under houses that sit atop stilts. In Tanzania, UNEP has backed an effort to build small-scale water treatment plants, some of which can operate without power. And in Kenya, a prison has benefited from a UNEP-led project to improve sanitation through green technology.
UNEP also leading a pilot in India to boost nutrient recovery from wastewater and recently conducted study to improve faecal sludge management in Africa.
Carvalho says ensuring safe and resilient sanitation systems requires international solidarity for funding and smart water management dovetailed with climate adaptation measures and context-specific nature-based solutions.
“We have the tools we need to safeguard the world’s sanitation systems and drinking water supplies,” says Carvalho. “What we really need is to start using them now.”
The UN-Water Summit on Groundwater will be held from 7 to 8 December in Paris. The summit will discuss sanitation and how it protects groundwater. It aims to bring attention to groundwater at the highest international level and will deliver a joint message to the UN 2023 Water Conference, urging policymakers to fully recognize the importance of groundwater and accelerate progress on sanitation to safeguard this precious resource.
For further information, please contact Riccardo Zennaro: riccardo.zennaro@un.org or Avantika Singh: avantika.singh@un.org
