26 Oct 2021 Story Water

Data, adaptation and finance key to managing flood risk

Photo: REUTERS

Last week’s flash floods in India, Nepal and Spain triggered by heavy rainfall are the latest in a string of water-related disasters from Germany to South Sudan to the United States.

Flood-related catastrophes have increased by 134 per cent since 2000, compared with the two previous decades, according to the World Meteorological Organization (WMO). As a recent report from the Intergovernmental Panel on Climate Change (IPCC) underscores, rising global temperatures are dramatically affecting the water cycle, making floods and droughts more extreme and frequent. It’s an issue that will be in the forefront of the minds of those attending the United Nations Climate Change Summit, known as COP26, in Glasgow, Scotland, at the beginning of November.

Flooding along the Pungwe River in Mozambique

Flooding of agricultural land in Africa can lead to hunger. Photo: Joakim Harlin/UNEP

Against that backdrop, the United Nations Environment Programme (UNEP) and partners have been working to help lessen the impact of flooding in countries around the world.

“UNEP doesn’t have a magic wand, but we work with partners to accelerate flood resilience, build capacity, promote sustainable development, and gather and analyse the all-important data to inform policymaking,” says UNEP freshwater ecosystems expert Lis Mullin Bernhardt. “We’re building resilience by advancing Sustainable Development Goal 6 on water and giving countries significant opportunities to advance their broader development and climate agendas effectively, consistently across sectors and with longer-term viability.”

Flooding destroys biodiversity, lives, livelihoods, infrastructure and other assets. It can also compound health hazards, such as cholera, as sewers overflow and freshwater and polluted water mix. Standing floodwater may encourage the breeding of malaria-carrying mosquitoes in some places. COP26 has been billed as a last chance to make significant progress in these and related flood mitigation and adaptation areas, such as flood early warning systems.

The WMO report makes a strong case for investing in integrated water resources management, a comprehensive framework for managing water resources and balancing social and economic needs while protecting ecosystems, such as wetlands that mitigate flooding.

Data tools

More accurate and reliable data are helping to pinpoint risks. The Flood and Drought Portal, maintained by UNEP-DHI (a UNEP centre of expertise dedicated to improving the management, development and use of freshwater resources from the local to the global level), aggregates and translates publicly available data from a range of sources, making it accessible to water authorities in a form they can use to support decisions at a local level. The portal uses the growing opportunities provided by satellite data and cloud solutions to improve preparedness, management and response to urban flooding, basin floods, droughts and coastal protection. 

Meanwhile, the Global Partnership for Sustainable Development Data, which works to ensure the new opportunities of the data revolution are used to achieve the Sustainable Development Goals (SDGs), has worked with partners, such as UNEP, to inform flood policy in Guinea, Senegal and Togo. It organized a three-phase capacity-building exercise on using the Flood and Drought portal.

The training has helped Senegal to improve data availability. “We learned how to explore and use data on deforestation, drought and floods in Senegal, which are not often collected at the national level,” says Gora Mbengue from Senegal’s Planning and Environmental Watch Department.

Flooding in Shaoguan, Guangdong Province, China in 2020.

Flooding in Shaoguan, Guangdong Province, China in 2020. Photo: Unsplash/Jéan Béller

Adaptation saves lives, resources

UNEP’s Adaptation Gap Report 2020 highlights the critical need for more climate change adaptation funding and the importance of nature-based solutions. Adaptation investments save money in the longer term: the Global Commission on Adaptation in 2019 estimated that a $1.8 trillion investment in adaptation measures would bring a return of $7.1 trillion in avoided costs and other benefits. Co-managed by the World Resources Institute and the Global Center on Adaptation and established by the Netherlands in 2018, the Commission served to raise the visibility of climate adaptation on the global agenda and advance concrete solutions. It was wound up in January 2021.

“Ecosystems-based approaches, like constructed wetlands, dedicated retention areas and restoring vegetation cover to help mitigate the impacts of floods, are gaining increased attention and funding, and form a core part of UNEP’s work in the area of climate,” says Bernhardt.

Within its mandate for SDG target 6.6, UNEP is working to conserve wetlands, which soak up excess water and release it slowly, thus mitigating the impact of flooding.

UNEP doesn’t have a magic wand, but we work with partners to accelerate flood resilience, build capacity, promote sustainable development, and gather and analyse the all-important data to inform policymaking.

Lis Mullin Bernhardt, UNEP freshwater ecosystems expert 

In Comoros, for instance, UNEP and partners are helping people harvest and retain water by rehabilitating 3,500 hectares of watershed habitat. The project aims to plant 1.4 million trees over the course of four years across the country’s three islands. For farmers living within increasingly parched and degraded watersheds, this ecological restoration will prevent their soils from drying-up and being washed downhill. The project is also improving weather forecasting systems and climate knowledge to help people change with the climate.

This example is from UNEP’s new ecosystem-based adaptation guidelines which contain the Opportunity mapping tool for Eco-DRR, that helps countries map out where ecosystems, such as mangroves, forests, coral reefs and seagrasses, overlap with human populations vulnerable to storms, flooding and landslides, and seeks to identify where ecosystem-based approaches will have the greatest impact.