* Any views expressed in this article are those of the author and not of Thomson Reuters Foundation.Addressing many of our water woes doesn’t necessarily require more money, just the ability to recognize the opportunities
Imagine if there was a way to increase water supplies, improve water quality, reduce the risks from floods and droughts, protect the environment and save money – all at the same time.
Well, there is.
Healthy forests, wetlands and grasslands, as well as sustainably managed crops and soils, can help regulate stream flows, enhance water storage and reduce pollution, thus providing a cleaner, safer and more reliable source water for downstream users. In urbanized areas, green roofs, walls and permeable pavement can accomplish much of the same. When appropriately managed, all of this so called ‘green’ infrastructure can substitute, augment or work in parallel with human-built (‘grey’) infrastructure.
The potential savings can be enormous. For example, three protected watersheds provide New York City with the largest unfiltered water supply in the USA. Investments in watershed protection have ended up saving the city more than US$300 million per year on water treatment operation and maintenance costs alone. The programme also serves as an alternative to building a water treatment plant, which would have cost between an estimated US$8 and 10 billion.
Yet water resources management remains heavily dominated by grey infrastructure. Evidence suggests that, worldwide, green infrastructure only accounts for about 5% of the total investment in water-related infrastructure and even less when compared to the overall expenditure in water resources management.
So why is there so little attention to green infrastructure and other nature-based solutions? There are several reasons. The current instruments of governments, from public policy to design codes, and the civil engineering focused expertise of service providers, has led to a certain inertia in the minds of policy makers and the general public. As an example, the image of a concrete wall or levee that keeps flood waters from coming in will, to many observers, appear much more tangible than the image of rehabilitated wetlands, which act like a sponge and store the same flood waters, thus providing a similar result.
We are not necessarily proposing to replace all grey infrastructure with nature-based solutions. There are examples where nature-based approaches offer the main or only viable solution (for example, landscape restoration to combat land degradation and desertification) and examples where only a grey solution will work (for example, supplying water to households through pipes and taps). But in most cases, green infrastructure can complement grey infrastructure in a cost-effective manner. So the objective is to find the most appropriate blend of green and grey infrastructure that maximize benefits and system efficiency while reducing overall costs and minimizing trade-offs.
The 2018 edition of the United Nations World Water Development Report focuses on the tremendous opportunities that nature-based solutions present for water. This is not merely a good idea – which of course it is – but an essential step to ensuring the long-term sustainability of water resources and of the multitude of benefits that water provides, including job creation, carbon storage, increase of biodiversity, food and biofuel production. Taking account of the substantial value of these co-benefits should further help tip investment decisions in favour of nature-based solutions.
Water security will not be achieved through business-as-usual approaches. Nature-based solutions offer a realistic, vital and affordable means to move beyond business-as-usual. Addressing many of our water woes doesn’t necessarily require more money or resources, just the ability to recognize the opportunities we’re missing and the readiness to do things differently.
Richard Connor is the editor-in-chief, United Nations World Water Development Report , United Nations World Water Assessment Programme (WWAP) of UNESCO and Stefan Uhlenbrook is the coordinator and director, United Nations World Water Assessment Programme (WWAP) of UNESCO.