C40 Voices: Seth Schultz, Director of Research, Measurement & Planning, on water resources for cities

Seth Schultz is C40's Director for Research, Measurement and Planning.

I recently attended The Nature Conservancy’s Global Water Summit in Chicago, where TNC, in partnership with C40 and the International Water Association released a landmark piece of research that assesses vulnerability to water stress in the world’s 500 largest cities.

Currently, most cities confront the challenges of water quality and quantity by consistently re-plumbing their watersheds based on increased demand, changing land use and impacts to their water basins. However, this piecemeal approach to water management is expensive and does not address the fundamental problem cities face: sharing a limited supply across multiple uses.

The Urban Water Blueprint report looks at 700 million people living in the world’s 100 largest cities that could benefit from water conservation efforts. While these 100 cities cover less than 1% of the earths land mass, their related watersheds cover 12% of the earth’s surface – roughly the size of Russia.

The good news, however, is that even though cities are often the minority water user within these larger water basins, they also have greater purchasing power than almost any other user.  What’s more, cities have strong power within their geopolitical boundary to take action on these issues as outlined in C40’s recent Climate Action in Megacities 2.0 report. And they’re taking action.

C40 Cities recently reported taking over 406 actions to reduce vulnerability to water stress, increase the sustainability of water supply, or improve water consumption efficiency.

C40 cities are subscribing to the “if you can’t measure it, you can’t manage it” philosophy when it comes to water: cities that have conducted a water stress vulnerability and risk assessment take 55 percent more actions than cities that have not. And these are no pilot projects – more than 50 percent of C40 city water management actions are on a city-wide scale.

Today, a city can easily predict the costs and output for a water treatment plant, benefitting from the industrial knowledge of similar treatment plants that have been built over the decades. This is not true for watershed conservation measures; while individual cases have been studied in depth, our ability to generalize the impact of conservation activities is limited, and there is no reliable mechanism for consistent delivery. If a city decides to explore the role of source water protection in its portfolio of capital investments, there are few examples from which to learn. Solving the issues of track record and delivery is a necessary step in enabling the replication and scale-up of these solutions.

That's where C40 comes in. C40 works through networks in which cities learn from each other. 

The report we launched today offers an ambitious, but very real way forward in which cities, conservationists, water utilities and regional governments can collaborate to help provide more sustainable, more efficient and more environmentally sound approaches to help manage one of our worlds most precious resources; fresh water.

Cities that embrace natural and engineered solutions cannot only meet future water demand; they can also reshape our planet for the better.