Water and climate: Rising risks for urban populations

Water is vital to a city’s growth and stability and is the backbone to healthy societies. But the threat of too much or too little water puts everything at risk. This report highlights how the cities facing the worst climate impacts are often those with the highest social vulnerability.

Right now, 90% of climate disasters are water-related, and the 4.4 billion people who live in towns and cities – especially in low-income countries – are on the frontlines.

As the climate crisis continues to throw the water cycle out of balance, many of the world’s largest cities are impacted in ways that are hard to anticipate and plan for. The frequency and magnitude of events such as floods and droughts are evolving due to climatic trends. And when water, sanitation and hygiene (WASH) services and systems cannot cope with intensifying and unpredictable climatic extremes, it is often the most vulnerable and marginalised people who suffer the worst impacts on their health, education and livelihoods, pushing them further into poverty.

This new research examines climatic trends over the past 42 years in the world’s 100 most-populated cities, plus 12 cities where WaterAid works. It analyses whether these cities are becoming more prone to floods, or to droughts, and how these changes affect the people who live there.

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Many cities experience “whiplash”; droughts that dry up water sources followed closely by floods that overwhelm infrastructure, destroying sanitation systems and contaminating drinking water.

Meanwhile, other cities are seeing dramatic climate reversals. Places accustomed to heavy rainfall are now facing droughts, while historically arid regions now grapple with unexpected floods. 

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The research also examines how these changes intersect with social and infrastructural vulnerabilities to threaten people’s access to safe and sustainable water, sanitation and hygiene services.

As two thirds of the global population are projected to live in cities by 2050, and climate hazards become more intense and erratic, there is an urgent need for decision makers to understand the threats to infrastructure and society, and to do much more to achieve and maintain universal and equitable access to WASH in cities.

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We call for:

• Global leadership to accelerate action on water. Governments and development partners must work through the existing multilateral platforms to deliver ambitious action on climate and water, including through the UNFCCC, the G7 Water Coalition and the G20 Call to Action on Strengthening Drinking Water, Sanitation, and Hygiene Services.
• Greater investment to tackle the water crisis. Development partners, multilateral banks and the private sector must work together to unlock investment in climate-resilient WASH systems that benefit the most vulnerable.
• National government leadership to urgently deliver water plans. Governments in affected countries must mainstream and implement WASH measures into their national and city-level climate adaptation plans with a focus on vulnerable groups, especially women and girls.
• Prioritisation of the most vulnerable communities. All decision-makers must urgently recognise overlapping vulnerabilities and prioritise the leadership and needs of women, girls and marginalised groups in climate-resilient WASH plans.

Top image: Women line up to collect water from a water kiosk in Sylvia Masebo Community, Lusaka, Zambia.