The team’s argument begins with a sober assessment of the global situation. Climate change is placing mounting strain on water and sanitation services, with floods contaminating shallow wells, droughts drying up springs, and erratic rainfall disrupting the piped networks on which growing urban populations depend. Each of these disruptions carries a direct public health cost, because unsafe water is a principal vehicle for cholera and other diarrhoeal diseases. In low-income and fragile contexts, the authors note, the need for increased investment in water and sanitation is urgent, but money alone will not close the gap. Equally important is enhancing the efficiency with which available financial resources are used, so that every dollar spent on pipes, pumps, treatment and household connections delivers the greatest possible reduction in disease risk.

This is where operational research enters the picture. Operational research, in the sense the authors use the term, is the systematic study of programmes as they are actually delivered, asking not only whether an intervention works under ideal conditions but whether it works, for whom, at what cost and with what unintended consequences when rolled out at scale by real institutions under real constraints. Randomised trials of water treatment technologies conducted in stable research settings have produced valuable knowledge, but their findings often translate poorly to the chaotic, rapidly changing environments of complex emergencies, where supply chains break, populations move, and the institutions responsible for maintenance may be weak or contested. The result is a persistent mismatch: the places with the greatest burden of waterborne disease generate the least evidence about how to reduce it.

To illustrate what a different approach looks like, the authors draw on their own experience conducting research embedded within a large-scale water supply infrastructure improvement programme in an urban, cholera-endemic area of South Kivu. The programme, implemented against the backdrop of one of the world’s most protracted humanitarian crises, aimed to upgrade drinking water services for hundreds of thousands of residents. Rather than standing apart from the implementers, the research team worked alongside them, shaping evaluation questions around the decisions that programme managers actually faced: which neighbourhoods to prioritise, how to design connections that households could afford, and how to measure whether improved infrastructure was translating into safer water at the point of consumption and fewer cholera cases at treatment centres.

The technical challenges of doing this well are considerable, and the article is candid about them. Measuring water quality in an urban African setting requires laboratory capacity, cold chains for reagents, and sampling frames that can keep pace with shifting neighbourhood boundaries. Measuring health outcomes such as cholera incidence depends on surveillance systems that may themselves be strained by insecurity and underreporting. Infrastructure programmes unfold over years, while funding cycles and political attention operate on shorter clocks, creating pressure to produce findings before the intervention has had time to take effect. The authors describe how pragmatic methods, including mixed-methods designs that combine quantitative water quality testing and epidemiological analysis with qualitative work on household behaviour and institutional dynamics, allowed the team to generate useful evidence despite these constraints, accepting some trade-offs in precision in exchange for relevance and feasibility.

Central to their argument is the idea that multi-stakeholder research partnerships are not a soft, diplomatic nicety but a methodological necessity in fragile settings. The South Kivu collaboration brought together international academic researchers, Congolese scientists, ministry officials, water utility staff and implementing organisations, each holding pieces of knowledge the others lacked. Local researchers understood the epidemiology of cholera in the region, the politics of water access and the practical realities of fieldwork in insecure areas. International partners contributed methodological expertise, analytical capacity and connections to the global evidence base. Implementers knew the engineering constraints and the programme’s decision points. When these perspectives are integrated from the design stage, the authors contend, studies are more likely to ask questions that matter, collect data that decision-makers will actually use, and survive the inevitable disruptions that complex emergencies inflict on any long-term project.

The partnership model also carries implications for capacity, which the authors treat as a first-class outcome rather than a by-product. Research in crisis-affected settings has too often followed a pattern in which external teams arrive, extract data, publish findings in journals inaccessible to local institutions, and depart, leaving behind little durable capability. By contrast, the South Kivu experience illustrates the role of research in strengthening capacities for both science and practice: Congolese doctoral and masters students gained training in study design, laboratory methods and data analysis; national institutions gained experience with rigorous evaluation; and programme staff gained a clearer understanding of how their interventions were performing on the ground. This reciprocal capacity building, the authors suggest, is what allows evidence generation to become a sustained national capability rather than a series of one-off foreign expeditions.

The cholera context gives the work particular urgency. South Kivu sits within one of the persistent hotspots of the seventh cholera pandemic, and the Great Lakes region has repeatedly seen explosive outbreaks driven by a combination of dense urban settlement, limited sanitation, and populations displaced by conflict. Cholera is exquisitely sensitive to water infrastructure: sustained access to safely managed drinking water and sanitation is the only durable route to eliminating transmission, which is why the global roadmap for cholera control places water and sanitation investment at its core. Yet the evidence on which infrastructure configurations deliver the greatest protection, and how to sequence and target investments in cities where full coverage is years away, remains surprisingly weak. Studies embedded in real programmes, like the one described in South Kivu, are among the few ways to close that gap, because they can observe the transition from inadequate to improved services as it happens, at a scale and in a setting where the findings are directly generalisable to other cholera-endemic cities.

The authors are careful not to oversell the model. Embedded research requires funders to accept longer timelines and greater uncertainty than conventional studies, and it requires implementing agencies to tolerate independent scrutiny of their work, which not all are willing to do. It demands genuine power-sharing, since partnerships in which local institutions are consulted but not empowered tend to reproduce the extractive patterns of the past. Ethical questions also intensify in complex emergencies, where participants may be vulnerable in multiple overlapping ways and where the research itself must never delay or distort the delivery of services that people’s survival may depend on. Navigating these tensions, the article suggests, is as much a part of the method as any statistical technique, and the learnings the authors distil are intended as practical guidance for the next team attempting something similar.

The way forward the authors sketch is one in which operational research becomes a standard component of water and sanitation investment in fragile and low-income countries, funded and planned alongside the infrastructure itself rather than bolted on afterwards or omitted entirely. As climate change intensifies pressure on water systems worldwide and urbanisation concentrates more people in underserved neighbourhoods of fragile states, the cost of flying blind grows each year. The South Kivu experience offers a concrete demonstration that rigorous, decision-relevant evidence can be produced even in one of the world’s most difficult operating environments, provided that research is treated as a partner to practice rather than its judge, and that the institutions closest to the problem are given the resources and authority to lead. If that lesson travels, the authors argue, the next generation of water investments in crisis-affected cities can be built on a far firmer evidentiary foundation than the last.

Subject of Research: Embedded operational research on water supply infrastructure and cholera risk in a complex emergency in South Kivu, Democratic Republic of the Congo

Article Title: Pragmatic water and health research in a complex emergency: Learnings and way forward

Article References: Gallandat, K., Saidi, J. M., Rumedeka, B. B., Machuel, D., Seon, A., Malembaka, E. B., Bugeme, P. M., German, E., Bompangue, D., Hutchins, C., Knee, J., Azman, A., & Cumming, O. (2026). Pragmatic water and health research in a complex emergency: Learnings and way forward. PLOS Water, 5(10), e0000646. https://doi.org/10.1371/journal.pwat.0000646

Image Credits: AI Generated

DOI: 10.1371/journal.pwat.0000646

Keywords: water and sanitation, cholera, operational research, complex emergency, Democratic Republic of the Congo, South Kivu, public health, research partnerships, capacity building, climate change, drinking water infrastructure, PLOS Water