Sustainably managing water in a changing climate

The Water Security (WS) Network will support cities to plan for and deliver best practice solutions on securing water supply and sustainably managing water in a changing climate. The WS Network complements the two existing networks focused on downstream water management (the Connecting Delta Cities Network, and the Urban Flooding Network) and supports cities in delivering holistic strategies and measures for sustainable water supply delivered in an efficient and equitable manner, while identifying opportunities for greenhouse gas emissions reductions in the water sector.

One in four of the world’s largest cities is currently water stressed and changing climate conditions will mean they face more frequent and intense impacts on their water increasing water scarcity, drought and deteriorating water quality. Almost 70% of C40 cities report substantive future risk to their water supply in the face of climate change, and the nearly 550 million residents in the 80% of C40 cities that rely on surface water for their water supply are especially at risk as warming temperatures increase the already substantial losses of surface water to evaporation.

The water sector also contributes greatly to our global energy use and related greenhouse gas emissions with 7% of total energy use attributed to water delivery. Furthermore, much of this energy is wasted in delivery; water losses in some cities with aging infrastructure can be as high as 70%, which also means a waste of the energy used to treat, pump and distribute this water.

The WS network will convene C40 city government officials from around the world to inspire one another, exchange experiences (including common pitfalls), and together develop new solutions in holistic, long-term urban water management so that each city may develop the knowledge, tools and techniques to improve their own water management systems. This network will also be informed by an evidence base of research on risks, challenges and actions in the urban water sector, C40 research being undertaken with the generous support of Grundfos.

Focus areas:

The network will determine a few key areas of focus to be developed into workstreams, wherein groups of cities would share best practice and challenges and work together to develop solutions through peer consultation and review. These focus areas may range from strategic high-level assessment of cities’ water systems and related political and economic opportunities, to technical operational knowledge exchange on topics like energy efficient distribution and treatment. The following topics are proposed focus areas for network workstreams:

  • Reuse and recycling
    Coordinated development and management of previously unutilised water resources.
  • Demand management
    Effective, equitable distribution and demand management, including optimising delivery mode, ensuring energy savings, and cultural and behavioural changes.
  • Strategy & institutional arrangements
    Outlining the mandates of relevant institutions to strengthen capacity, and knowledge; and developing strategy on integrated water and data management.
  • Watercourse quality management
    Managing land use and pollution sources both within urban areas and cross-boundary outside of urban areas.

Cities participating in the network: Auckland, Bangkok, Barcelona, Bogotá, Buenos Aires, Cape Town, Delhi, Freetown, Istanbul, Lagos, London, Madrid, Medellín, Melbourne, Mexico City, Phoenix, Quezon City