Significant emission reductions possible through global water sector: new research reveals

8 December 2023

Finance from high-integrity voluntary carbon markets can drive access to safe water for millions.

4% of the world’s carbon emissions could be saved within the global water sector, initial findings from research commissioned by WaterAid’s Resilient Water Accelerator (RWA) and Voluntary Carbon Market Integrity Initiative (VCMI) reveal today.

Launched as the UNFCCC COP28 is underway in Dubai, findings indicate over 1.3 billion CO2e of mitigation potential per year in the global water sector, equivalent to nearly half of the EU’s annual emissions – and ensure greater access to safe water for millions of people across emerging markets, living on the frontline of climate change.

WaterAid’s RWA states that to achieve this, collaboration is essential between countries, the water sector and the broader climate finance community. Harnessing market mechanisms such as high-integrity voluntary carbon markets (VCMs) can deliver a triple win: emissions reduction, improved water security, and improved access to safe water and sanitation for millions of people.

In practice this would mean generating carbon credits from projects which deliver carbon savings as well as water benefits, such as, improved drinking water access in developing countries, reduced methane emissions from latrines and centralized wastewater treatment plants or restored coastal environments.

In its initial stages, the research has looked at where emissions come from within the water sector and found that delivering improvements in coastal blue carbon, wastewater treatment, drinking water treatment, irrigation as well as energy efficiency broadly, water security could be improved while generating carbon credit emission reductions. These credit estimates are show in the figure below. 

Potential total global adressable emissions reduction credits by sector
Potential total global adressable emissions reduction credits by sector

Speaking at COP28, Kate Hughes CBE, Resilient Water Accelerator CEO, called for investment in water to be top of the agenda at COP, saying: 

"The impacts of climate change are felt through water, whether that be too little or too much.  

"This research identifies a significant opportunity to cut carbon emissions while also boosting vital water services for millions of people in low and middle income countries dealing with the devastating impacts of climate change.

"At COP we need to see international partnerships fostering meaningful climate action across society, policy makers, and business to ensure investment from this untapped potential reaches communities on the frontline of the climate crisis."

Lydia Sheldrake, VCMI Director of Policy & Partnerships, said:  

“These initial findings show the urgency of upgrading global water systems to achieve a low-carbon, just transition. If the world is going to get on track, we need to scale investment in emissions reductions well before 2030. 

"High-integrity voluntary carbon markets provide one part of the solution. Now we need concerted collaboration and ramped up support to countries and communities to implement high-quality projects and mobilize demand, so finance flows to those who need it most.”

This work comes at a critical time as seen at COP, the increasing recognition that the  climate crisis is a water crisis. 90% of all natural disasters are water-related, whether it be experienced through too little or too much water. 

From flood defences to drought resistance, the solutions are out there. But more investment and management are needed now to develop robust and reliable water, sanitation and hygiene systems that can withstand any climate. 

The Resilient Water Accelerator is in a unique position to deepen access to the Voluntary Carbon Market through its work building and strengthening efforts to develop robust monitoring and management of water risk and engaging with finance organisations such as African Development Bank, 2030 Water Resources Group and African Finance Corporation.


Notes to editors

The research is due to be published in early 2024, following stakeholder engagement on interim findings at COP28. It was commissioned by WaterAid’s Resilient Water Accelerator (RWA) and VCMI in collaboration with Gold Standard, and is being conducted by the University of Colorado Boulder and Castalia Advisors. 


  1. The Resilient Water Accelerator is a global initiative that brings relevant decision makers, technical experts and investors together to create connections that address water risk, strengthen resilience and attract public and private finance. Our goal is to demonstrate the business case for more and better public and private investment in water-related deals that strengthen resilience for communities on the front lines of the climate crisis. It’s important that these are replicable elsewhere so that millions more can benefit. We are currently operating in Nigeria and Bangladesh and exploring potential work in more countries.
  1. The Voluntary Carbon Markets Integrity Initiative (VCMI) is an international non-profit organization with a mission to enable high-integrity voluntary carbon markets (VCMs) that deliver real and additional benefits to the atmosphere, help protect nature, and accelerate the transition to ambitious, economy-wide climate policies and regulation. 
  2. This analysis was undertaken by Evan Thomas, Christina Barstow, Laura MacDonald, John Ecklu, Katie Fankhauser and Alex Johnson at the Mortenson Center in Global Engineering and Resilience at the University of Colorado Boulder, and developed in collaboration with the Sustainable Markets Initiative, WaterAid, HSBC, the Voluntary Carbon Markets Initiative, and Gold Standard, and supported by the Mortenson Center in Global Engineering at the University of Colorado Boulder, the Moore Foundation, and the Autodesk Foundation. 
  3. Castalia is the trusted advisor of corporations, utilities, governments, international agencies and infrastructure investors around the world. They solve complex, strategic assignments and deliver sustainable, measurable results. The team from Castalia Consultants includes David Ehrhardt, F Javier Manzanares, Tony Clamp, Jane Zhao, Ilan Adler, Joseph Sax, Yulian Fan, and May Tint Tel.

Or call our after-hours press line on +44 (0)7887 521 552  


WaterAid is an international not-for-profit determined to make clean water, decent toilets and good hygiene normal for everyone, everywhere within a generation.  We work alongside communities in 22 countries to secure these three essentials that transform people’s lives. Since 1981, WaterAid has reached 28.5 million people with clean water and 29 million people with decent toilets. 

For more information, visit our website, follow us on Twitter @WaterAidPress, @WaterAidUK, @WaterAid, or find us on Facebook, LinkedIn or Instagram

  • 703 million people in the world – almost one in ten – do not have clean water close to home. 
  • 1.5 billion people in the world – almost than one in five – do not have a decent toilet of their own. 
  • Over 300,000 children under five die every year from diarrhoeal diseases caused by poor water and sanitation. That's more than 800 children a day, or one child every two minutes. 
  • Investing in safely managed water, sanitation and hygiene services provides up to 21 times more value than it costs. 

[1] WHO/UNICEF (2021) Progress on household drinking water, sanitation and hygiene 2000-2020. Joint Monitoring Programme. Geneva: World Health Organisation. 

[2] WHO/UNICEF (2021) Progress on household drinking water, sanitation and hygiene 2000-2020. Joint Monitoring Programme. Geneva: World Health Organisation. 

[3] WaterAid calculations based on: Prüss-Ustün A, et al. (2019). Burden of Disease from Inadequate Water, Sanitation and Hygiene for Selected Adverse Health Outcomes: An Updated Analysis with a Focus on Low- and Middle-Income Countries. International Journal of Hygiene and Environmental Health. vol 222, no 5, pp 765-777. AND The Institute for Health Metrics and Evaluation (2020) Global Burden of Disease Study 2019. Seattle, WA: University of Washington. 

[4] WaterAid. (2021) Mission-critical: Invest in water, sanitation and hygiene for a healthy and green economic recovery.