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In September 2021, Hurricane Ida dropped more than six inches of rain on New York City in a matter of hours. Roughly half of that rainfall, 3.15 inches, fell within the first hour—nearly twice the rate the city’s infrastructure was designed to handle. 

At 11am that day, I got a call from my daughter’s school in the outskirts of the NYC metropolitan area asking me to collect my daughter ASAP. The school basement was filling with water … fast. By the end of the day, the school was shuttered, and the surrounding community evacuated. Meanwhile, outside my front door in suburban New York, neighbours were piling the contents of their basements onto the sidewalk. ‘The neighbourhood’s shit is in my basement!’ one exclaimed. Social media was filled with discordant images of flooded streets and Teslas floating through them.

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Ann provides strategic direction and oversight of UNICEF’s global portfolio on sanitation, hygiene and institutional WASH. She is a Canadian environmental engineer and a founding member and co-lead of the Climate Resilient Sanitation Coalition.  

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Reading Time: 8 min.

New York City’s century-old combined sewerage system (in which wastewater and rainwater share the same pipes) is easily overwhelmed by storm events. Roughly 30 billion gallons of raw sewage are dumped into local waterways every year. With over half the city using combined sewers, it is not surprising that 43% of backups in 2023 were attributed to excessive rain. With climate change, this situation is predicted to get worse before it gets better.

And the news is full of crap lately. Raw sewage has been running down the streets in England and flooding the Thames in London during heavy rains. In Dubai, heavy rains and flooding prompted the government to launch a $22 billion investment in sewage infrastructure. 

The bad news won’t stop anytime soon. As changing climate leads to more extreme weather events, heavy rainfall overwhelms aging sewage and wastewater infrastructure in modern, developed cities. My NY suburb experience is testament to this trend. 

Sanitation affects climate; climate affects sanitation

You may not realize that poor sanitation contributes to the climate problem by generating greenhouse gases and damaging coastal and freshwater ecosystems that function as precious carbon sinks. Few people realize the potential climate impact of sanitation problems: half the global population lacks safe sanitation, which if poorly managed, both emits methane and is vulnerable to climate disasters.

I’ve had the opportunity to live in a number of different continents over the last two decades, and what I’m seeing is that climate is the great leveller when it comes to sanitation. Whether you live in New York or Jakarta - we’re all in this together for the foreseeable future and the aperture of learning needs to expand. The solutions to this problem- non-sewered approaches, circular economy, behaviour change – are already taking root in places like Kenya and Indonesia and there is much to learn from these experiences.

As UNICEF’s global sanitation lead, climate resilient sanitation is a major priority relating to securing investments on the ground and ensuring future investments in the sector are climate proof. As a citizen living in a NY suburb, I’m concerned global learning is siloed between industrial and emerging contexts, and there’s a missed opportunity for two-way dialogue in the face of a common challenge. 

What is Climate Resilient Sanitation?

Climate Resilient Sanitation, or CRS, refers to sanitation systems that minimize greenhouse gas emissions, and reduce the impacts of climate events on service delivery. It encompasses infrastructure (e.g., latrines, treatment plants, piping, etc.), as well as services (e.g., pit emptying, transporting sludge, etc.).

Bringing global lessons together to connect better programming to increased financing

Emerging economies, out of sheer necessity, are on the forefront of innovation when it comes to leapfrogging legacy infrastructure and finding innovative ways to deal with the growing crisis in sanitation. This is due to rapidly growing and unplanned cities that give way to more decentralized off-grid solutions, the acute nature of climate related impacts on households – especially impoverished, vulnerable household, the fact that households drive the majority of investments in sanitation and the need to keep public health outbreaks such as cholera, which are increasing in intensity and spread, at bay. 

By looking at waste from a climate perspective rather than simply as an infrastructure challenge, emerging economies have leveraged synergies with food and water security more seamlessly. 

Take for instance the practise of wastewater reuse which is commonplace in many places in the Middle East, likewise the practise of recycling faecal sludge as fertilizer in many parts of Asia. This positioning of sanitation as part of a circular economy and at the nexus between water resources management and food production positions it as a lynchpin in climate action plans. 

The dependence of agriculture on industrial fertilizers, containing phosphorus from mined phosphate rock, is yet another example. Phosphorus has a checkered past of being extracted from a variety of non-renewable sources involving environmental degradation, human rights abuses, and risky locations. But phosphorus can also be extracted from manure (human or animal) and this is already being done in many emerging markets globally. As we move closer to exhausting mined phosphate reserves, reconsidering how our food is produced in conjunction with how it is processed may need to come full circle through our sanitation systems. 

The old adage ‘dilution is the solution’ has brought us to a junction where wastewater dumped into aquatic ecosystems is a leading threat to marine and freshwater ecosystems. Seabed grasses and mangroves which play a significant role in water resources management and are significantly more effective as carbon sinks than terrestrial forests. We see the catalytic role that effective sanitation systems could play in mitigating environmental damage and the ability that we have to mitigate one of the greatest threats to aquatic ecosystems – so why aren’t we doing it? 

Sanitation is first and foremost a public health intervention and without it, there is little separating us from 19th century illnesses that lurk within human faecal waste. With accelerating climate change, we’re seeing an increase in both the amount of disease and the kinds of diseases spread more widely globally threatening health security. 

Considering the links to health, environment and climate changing emissions, sanitation is central in accelerating climate action. 

New Annex reflecting global expertise and providing support to country climate action planning

I’ve spent decades working on sanitation projects around the world and it’s exciting to see that finally, collective efforts are being made to bring these lessons together. I’m talking about a new addition to the Green Climate Fund’s Water Security Guidance that will focus specifically on Climate Resilient Sanitation. Led by the Climate Resilient Sanitation Coalition (CRSC), this new piece of guidance will consolidate what we know about the hazards of sanitation to climate and climate to sanitation, the solutions to this crisis and how to connect climate finance to this critical sector. It will be an invaluable resource to countries looking to include sanitation in their National Adaptation Plans and connect climate finance to sector financing. 

In 2024, the CRSC is now over 25 organizations large, representing thousands of practitioners. At COP 29, the Coalition will unveil this resource to support country action planning. The advantage of CRS is that we already know how to do it – climate resilient sanitation is simply good sanitation. We have the knowhow, the approaches, and the experience to implement CRS. It is not disruptive to an entire sector – rather it is accelerating good practice within the sanitation sector. The experiences we can expect to hear about in the Green Climate Fund’s Sanitation Guidance document will include how to support smart household investments in sanitation, non-sewered and circular economy approaches that keep waste efficiently and safely managed and reused to prevent contamination and generation of excessive greenhouse gases. The missing piece is financing, and our hope is that the Annex will help unlock the funds to implement CRS globally. 

While definitions, indicators and processes for defining and monitoring climate resilient sanitation are happening globally at the moment, there is also an opportunity to reposition sanitation as a central driver of climate action – given its strong links to food and water resources management as well as health security and the fact that this is a sector that looks past the doom and gloom forecasting associated with climate to tractable and impactful solutions with immediate results. 



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