Beyond Flood Control: A Scoping Review Deciphering the Co-benefits of Nature-Based Flood Risk Reduction for Healthy Ageing in China

China’s Sponge City program was conceived as an engineering answer to a hydrological problem: how to keep rapidly expanding urban areas from drowning under increasingly intense rainfall. A new scoping review argues that the program, and nature-based flood risk reduction more broadly, is quietly doing something far more ambitious than managing stormwater. Published in the International Journal of Disaster Risk Science, the review systematically maps the qualitative evidence that flood-focused green infrastructure in China is also generating a cascade of health and social benefits for older adults, positioning these interventions as foundational infrastructure for resilient, age-friendly communities.

The study arrives at the intersection of two defining challenges of the twenty-first century: climate change and population ageing. Their convergence is particularly acute in China, which faces both a rapidly ageing population and an escalating frequency of devastating floods that cause annual economic losses exceeding ten billion US dollars. For older adults, floods carry risks well beyond immediate physical danger, including heightened rates of injuries, post-traumatic stress disorder, depression, and the exacerbation of diabetes and cardiovascular and respiratory conditions. These outcomes directly undermine healthy ageing, defined by the United Nations Decade of Healthy Ageing as the process of developing and maintaining the functional ability that enables well-being in older age.

To capture how nature-based solutions might counteract these harms, a research team led by Binhua Fu and Joseph Kimuli Balikuddembe of Sichuan University’s Institute for Disaster Management and Reconstruction conducted a scoping review following the Arksey and O’Malley framework and the PRISMA-ScR reporting guidelines. The team searched PubMed, Scopus, and Google Scholar for qualitative studies published between 2000 and early 2025, focusing on research that examined nature-based solutions for flood risk reduction—such as Sponge City infrastructure, green infrastructure, wetland restoration, and ecosystem-based adaptation—in settings across mainland China. Of 622 retrieved records, only 13 studies met the eligibility criteria, a finding that itself underscores how nascent and fragmented this evidence base remains.

The analytical machinery behind the review is worth noting for its technical sophistication. The researchers extracted data into six healthy ageing outcome domains aligned with the World Health Organization’s conceptual framework: physical activity and mobility, mental health, cognitive functioning, well-being and social support, environmental quality, and economic security. They then employed narrative synthesis alongside a Sankey diagram analysis, generated in R using the networkD3 package, to visualize weighted flows connecting geographical context, flood type, intervention type, and health co-benefit. This multi-level edge-list approach, in which each conceptual connection was weighted by its frequency across eligible studies, provided a quantitative representation of the dominant pathways within the qualitative literature.

Geographically, the evidence base spans at least nine provinces and provincial-level municipalities, with case studies concentrated in major urban centers such as Wuhan, Shanghai, and Guangzhou, and in designated pilot Sponge Cities including Guiyang and Ningbo. Temporally, the field is moving fast: ten of the thirteen included studies were published from 2020 onwards, coinciding with the scaling of China’s Sponge City Program amid mounting climate risks. Urban or pluvial flooding dominated the literature, addressed in ten of the thirteen studies, with fluvial, riverine, and general flooding covered by single investigations. Permeable pavements, rain gardens, bioswales, green roofs, and wetland restoration were consistently perceived as effective at reducing surface runoff and easing pressure on drainage networks.

The synthesis’s central revelation is the breadth of co-benefits these interventions deliver. The most prominently documented domain was psychosocial well-being and social support: aesthetically pleasing, accessible green spaces became hubs for conversation, leisure, and recreation, directly strengthening social and peer support networks and mitigating loneliness among older residents. Mental health benefits followed closely, with one study in Guangzhou linking the use of urban green infrastructure to measurable decreases in anxiety, dysphoria, and emotional exhaustion, and other studies reporting stress relief, relaxation, and high perceived aesthetic and health value. Physical activity and mobility improved as Sponge City features provided convenient, walkable spaces after rain, while urban parks encouraged walking and cycling.

Environmental improvements formed a cross-cutting co-benefit with direct implications for independent living. Studies reported enhanced air quality, noise mitigation, and cooling effects that reduce urban heat islands, creating safer and more comfortable outdoor environments for older adults. Cognitive functioning evidence was thinner but tantalizing: a single study associated urban green infrastructure use with memory enhancement, suggesting a possible pathway for NbS to support cognitive health in later life. Economic and community participation benefits emerged from multifunctional designs that integrated productive landscapes, including community engagement in risk-adaptive agriculture within flood detention zones and the use of green infrastructure spaces for vegetable and flower gardens—activities representing livelihood diversification, economic savings, and meaningful occupation for retired residents.

The review’s authors are equally candid about what the evidence lacks. Their analysis identified five principal gaps: an exclusively urban focus that neglects rural elderly populations; a methodological reliance on perceived rather than objectively or clinically measured benefits; a conceptual gap in which older adults appear only as incidental subsets of broader studies rather than central subjects of gerontological research; a thematic gap with cognitive function and nutrition severely underexplored; and an economic gap in the absence of quantified financial impacts on older persons. Sample sizes for older adult subgroups varied enormously, from as few as three retired persons to 95 participants aged 56 and above, and several key studies failed to report age-disaggregated data at all.

The policy implications are nonetheless substantial. The authors argue that the co-benefits provide a tangible pathway to operationalize China’s parallel national commitments to its “ecological civilization” vision and the Healthy China 2030 strategy, framing Sponge City rain gardens and urban wetlands not as drainage projects but as practical manifestations of a dual mandate: managing floodwater while creating the green, accessible environments that promote physical activity, mental restoration, and social connection. The economic case is compelling, the authors contend, because fostering environments that support activity, well-being, and cohesion can function as primary prevention, potentially reducing the incidence and severity of age-related chronic conditions and easing the mounting financial burden on China’s social and healthcare system—a perspective consistent with the One Health paradigm that treats investments in ecosystem health as direct investments in human health.

The rural blind spot carries particular equity weight. Rural communities in China are often on the front lines of riverine and pluvial flooding, yet they remain conspicuously absent from research on nature-based co-benefits, a disparity the authors warn risks exacerbating health inequalities among the elderly. They point to low-cost, replicable approaches such as flood-adaptive farming, grassland management, and riparian ecosystem restoration as candidates for scaling in rural settings, where older residents may be even more dependent on their immediate environment for both income and social connection.

The study’s limitations also shape its recommendations. The review was restricted to English-language publications, potentially excluding relevant Chinese-language studies, and, as is standard for scoping reviews, no formal critical appraisal of individual study quality was conducted. The predominance of qualitative and mixed-methods designs, while essential for understanding lived experiences and contextual factors, means the magnitude of health impacts remains unmeasured. The authors urge researchers to adopt longitudinal and mixed-methods designs employing validated health metrics, and call on policymakers and urban planners to intentionally design and evaluate nature-based solutions with geriatric outcomes as a primary objective, ensuring equitable distribution between urban and rural settings.

For a country that simultaneously confronts an “aging tsunami” and intensifying floods, the message of this review is that flood control and healthy ageing are not separate policy problems but two faces of the same infrastructure investment. If future research can move beyond perceived benefits to establish causal pathways and quantify costs, nature-based flood risk reduction may prove to be one of the most cost-effective preventive health strategies available to ageing societies in China and far beyond its borders.

Subject of Research: Beyond Flood Control: A Scoping Review Deciphering the Co-benefits of Nature-Based Flood Risk Reduction for Healthy Ageing in China

Article Title: Beyond Flood Control: A Scoping Review Deciphering the Co-benefits of Nature-Based Flood Risk Reduction for Healthy Ageing in China

Article References: Fu, B., Balikuddembe, J. K., Lu, Y., Yang, A., Di, B., Tian, B., & Reinhardt, J. D. (2026). Beyond Flood Control: A Scoping Review Deciphering the Co-benefits of Nature-Based Flood Risk Reduction for Healthy Ageing in China. International Journal of Disaster Risk Science. https://doi.org/10.1007/s13753-026-00741-x

Image Credits: AI Generated

DOI: 10.1007/s13753-026-00741-x

Keywords: Beyond, Flood, Control, Scoping, Review, Deciphering, Co-benefits, Nature-Based, Risk, Reduction, Healthy, Ageing