The theme of this year’s World Water Day is Water and Climate Change. This reflects a growing understanding within policy and practice spheres that the two are inextricably linked, and that water is also integral to climate change mitigation and adaptation. People, societies and economies directly experience climate change through water, with the poorest and most vulnerable being disproportionately affected.
Climate change is altering the global water cycle, leading to increased variability and unpredictability. This includes more severe and frequent floods, storms and droughts. Across the globe, we are already experiencing widespread negative impacts of this variability and unpredictability; from Cape Town’s ‘Day Zero’ water crisis in 2018 to Mozambique being hit by two intense Cyclones in 2019. Water scarcity will be further exacerbated by climate change. The UN estimates that by 2050, 5.7 billion people will be living in areas experiencing water scarcity for at least one month per year.
Too much or too little water at the wrong times or of the wrong quality threatens sustainable development. Drought is a key risk to the agricultural and pastoral sectors of the G5 Sahel countries – Burkina Faso, Chad, Mali, Mauritania and Niger – and changing rainfall patterns due to climate change are projected to decrease crop yields and alter traditional pastoral corridors. (For more on this, read the K4D Emerging Issues Report on unmet needs and opportunities for climate change mitigation and adaptation in the G5 Sahel). In Nigeria, climate change impacts on rain-fed agriculture will disproportionately affect women, as women comprise a large percentage of poor, small-scale, rain-dependent farmers. (For more detail, read the K4D report on water-related climate change impacts in Nigeria).
But, there is hope if we act together and act now.
Three key areas for action, at both the policy and practice levels, include climate-resilient water management; nature-based solutions; and increasing climate finance flows to water adaptation in developing countries.
1. Climate-resilient water management
Climate-resilient water management emphasises solutions that are both robust (can perform well across a range of possible futures) and flexible (can respond to unexpected shocks and long-term uncertainty). Climate change undermines a key assumption within traditional water management, that climate is stationary. Planners, water managers and policymakers need new tools to help them adapt to the uncertainty around how the water cycle is changing. Useful new tools include Climate Risk Informed Decision Analysis, a stepwise approach for infrastructure investments and water resources management that combines the latest science for climate stress testing and adaptation strategy development. This includes considering both nature-based solutions and grey infrastructure, and source water resilience. This methodology has been applied in Zambia, increasing the resilience of Lusaka’s main water treatment facility.
2. Nature-based solutions
Nature-based solutions, such as wetland restoration, mangrove conservation, and preserving flood plains can increase water availability and quality, and reduce the risks from water-related disasters. They can also play a dual role in tackling climate change, supporting both mitigation and adaptation outcomes. For example, mangrove forests store carbon and act as natural flood defences, making their conservation a win-win for nearby communities and the global ecosystem. Nature-based solutions can also involve using or mimicking natural processes. China is developing ‘sponge cities’; investing in green infrastructure innovations which can absorb rain and floodwater, for example through wetland development to store rainwater and permeable pavements so that floodwater can drain into the soil.
3. Climate finance
Climate finance is currently not reaching the most vulnerable. It is estimated that only six per cent of global climate finance is spent on adaptation, with an even smaller proportion of this being spent on water-related adaptation. Engaging investors is one way to boost resilient water infrastructure investment to address climate change. Investors are becoming increasingly aware and interested in water and climate risks and how to climate-proof investments. However, strong future growth will depend on increased confidence and transparency. Initiatives, such as the Water Infrastructure Criteria of the Climate Bonds Standard, launched in 2018, provide tools to support this. Large water investments are often funded through bonds, and the Criteria provide a consistent mechanism for bond issuers to identify the types of water projects that should be included in green bonds, and, enables investors to identify water projects that will have climate related benefits. This will ultimately help to mobilise finance for water projects that have mitigation, adaptation and resilience benefits. The Criteria has since been used to certify over USD 9 billion in water resilience bonds in Nigeria, South Africa and China, amongst others.
Rachel Cooper, based at University of Birmingham, is a researcher on the K4D (Knowledge, Evidence and Learning) programme. She is currently leading a K4D Learning Journey on Water Security for the Department of International Development (DFID). The Learning Journey aims to increase DFID staff’s learning on water security and climate change.