Alarm bells rang loud in 2024 in Cape Town in South Africa and Barcelona, Spain, as wells were running critically dry. In both cities severe water use restrictions were imposed on citizens after facing three consecutive years of drought. In Cape Town residents were limited to 50 litres per person daily, while Barcelona’s metropolitan aimed to keep consumption below 200 litres per day.
City dwellers are particularly exposed to dwindling water resources due to high soil sealing rates, limited ground water storage capacities, as well as added challenges that come with increased temperatures due to the urban heat island effect. Twice as many urbanites as today – an estimated two billion - are expected to be exposed to drought risk by 2050.
Fuelled by climate change, increasing temperatures make soils run dry more quickly. The variability in rainfall reduces groundwater to critically low levels, especially during periods when water is most in demand. We are seeing the duration, frequency and severity of droughts increase in many parts of the world. In Europe, for example, the number and duration of droughts increased by 29% since 2000 compared to the previous two decades.
France’s capital, Paris, may not yet be in the spotlight for water shortages like Cape Town or Barcelona, but drought is an emerging threat for both residents and authorities. The historically wet 2024 might suggest otherwise, yet back-to-back droughts in 2022 and 2023 left record water deficits in their wake. In 2019, authorities restricted agricultural water use to protect essential supplies and in 2003 drought ravaged over 60% of crops. The shifting extremes reveal how climate change is reshaping rainfall patterns, heightening the risk of alternating droughts and heavy rains.
While Paris relies less on agricultural production for its economic wellbeing than other regions, water scarcity has important ripple effects: energy production relies significantly on not only sufficient, but also sufficiently cold water. Industry and riverine transport are reliant on a constant water supply. In this report we show that a severe drought could cost the Parisian economy as much as EUR 2.5 billion – a figure that does not capture the detrimental and perhaps irreversible impacts on ecosystems and the various water resources the supply depends on.
This report highlights that historically robust water supply infrastructure may not be enough to adapt the Paris Metropolitan area to more severe social, environmental and economic impacts caused by droughts in the future. Through better assessments of exposure and vulnerability to droughts governments can make more informed decisions on policy design and investment in drought risk reduction measures. Reinforcing measures on both water supply as well as the demand side can help to maintain the remarkable drought resilience levels enjoyed by Parisians to date.
Jo Tyndall
Director of the Environment Directorate
OECD