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Water and Disasters

Most disasters are water-related. Floods, landslides, storms, heat waves, wildfires, extreme cold, droughts and waterborne disease outbreaks are all becoming more frequent and more intense, mainly due to climate change.

The impacts of disasters are exacerbated by urbanization and degradation of natural environments. Improving the resilience of water and sanitation services and protecting ecosystems will be key to surviving a climatically uncertain future.

The issue explained

Most disasters are water-related and climate change is increasing their frequency and severity. Poor communities are more vulnerable to the impacts of disasters, widening inequalities and undermining sustainable development.

The impacts of disasters include loss of life and damage to water and sanitation infrastructure, such as waterpoints, wells, toilets and wastewater treatment facilities.

In the aftermath of disasters, infectious disease outbreaks are common due to the spread of sewage, the breakdown in water and sanitation services, and diminished ability to practise good hygiene.

The degradation of natural environments makes the impact of water-related disasters worse. Loss of natural ‘buffers’ such as trees, river bank-side vegetation, wetlands and coastal mangroves reduces protection from flooding.

Rapid urbanization can concrete over large areas of land, channelling run-off too rapidly into storm drains, quickly overwhelming the system and leading to catastrophic flooding of streets and subways.

Lack of cooperation across national boundaries can mean that action by one party or parties upriver, such as release of sewage or changes to flow, can have devastating consequences for communities downstream across the border.

The increasing economic cost and toll of disasters are driving governments and humanitarian organizations to focus more attention on preparedness, prevention and addressing the root causes of vulnerability.

The way forward

Adaptation of water and sanitation infrastructure is vital for the resilience of societies and natural environments to increasing numbers of disasters. Initiatives include:

  • Enhanced water storage
  • Climate-proof infrastructure
  • Flood- and drought-resistant crop varieties
  • Forecasting and early warning systems
  • Land use planning and associated capacity building.

All countries must have a disaster risk reduction strategy that has water at its centre. The Sendai Framework for Disaster Risk Reduction, adopted by UN Member States in 2015, emphasizes water management as essential for reducing the occurrence and impacts of water-related disasters.

Facts and Figures

  • Around 74% of all natural disasters between 2001 and 2018 were water-related and during the past 20 years, the total number of deaths caused only by floods and droughts exceeded 166,000, while floods and droughts affected over three billion people, and caused total economic damage of almost US$700 billion. (UN WWDR,2020)
  • Every $1 invested in making infrastructure disaster-resilient saves $4 in reconstruction. (UNDRR)
  • The vast majority of natural disasters (over 90%) are water-related, including drought, flood and tropical storms, with significant impact on societies and the economy. (UNEP 2015)
  • Floods, droughts and storms have affected 4.2 billion people (95% of all people affected by disasters) and caused US$1.3 trillion of economic losses since 1992 (WCDRR 2014)
  • The impact of extreme natural disasters is equivalent to a global $520 billion loss in annual consumption, and forces some 26 million people into poverty each year. (World Bank 2016)
  • More than 2 billion people are living in countries under water stress and 3.6 billion people face inadequate access to water at least one month per year. (WMO 2021)
  • Water-related hazards have increased in frequency for the past 20 years. Since 2000, flood-related disasters have increased by 134%, and the number and duration of droughts also increased by 29%. (WMO 2021)