Cities over the past century have become the driving force of the global economy. Accounting for over half the world’s population and generating around 80% of global GDP cities provide numerous opportunities for development and growth.
Risks and challenges of cities
Cities however bring about risks and challenges to people and the environment. Around 30% of all water is consumed by cities with a large share of it returned back to the environment as wastewater, often in a degraded state. As the world continues to urbanize demand for water from cities is projected to increase by 50-70% Click & Tweet! . With one in four cities already experiencing water insecurity climate change is likely to add pressure on cities to access clean, adequate supplies of water.
Cities in low-to-medium income countries most at risk
Cities in low-to-medium income countries are most at risk from water insecurity and climate change and have low economic capacity to adapt: the annual costs of adaptation for the period 2010-2050 is estimated to range between $71.2 billion and $81.5 billion depending on the climate scenario, with urban areas likely to bear more than 80% of these costs.
Floods too impact water availability
It is not only droughts that cities need to prepare for but storms and floods that impact the quality of water available for residents, businesses and institutions. Flooding events can degrade the quality of surface water and groundwater Click & Tweet! , cause loss of life and property and disrupt local economies. Meanwhile, heat waves and variable levels of precipitation will diminish the availability and quality of water while increasing demand.
Easing the cost of adaptation to water insecurity
To ease the costs of adaptation to water insecurity the World Bank recommends three adaptation strategies that are economically beneficial, particularly to low-to-medium income countries:
- Enhance awareness among high-level policymakers about climate risks and the availability of economically-sound adaptation options
- Develop knowledge sharing and collaborative platforms for all stakeholders, managing or affecting urban water supplies, to participate in
- Assure adequate investment financing, including funding from multilateral development banks, governments and the private sector
Climate change adaptation in cities does not always have to involve costly infrastructural solutions: instead it can involve soft strategies that mitigate risks.
*Robert C. Brears is the author of Urban Water Security (Wiley). Urban Water Security argues that, with climate change and rapid urbanization, cities need to transition from supply-side to demand-side management to achieve urban water security.