The core observation is deceptively simple. Much of the water infrastructure in the United States, Europe and Japan was built during the mid-twentieth century, with design lives of fifty to a hundred years now expiring in large waves. The American Society of Civil Engineers’ most recent report card gives the sector grades that reflect chronic underinvestment, while the United Nations University has flagged ageing water storage infrastructure as an emerging global risk. Meanwhile, the United Nations Department of Economic and Social Affairs projects that the share of the world’s population over 65 will continue to climb steeply through mid-century, with the fastest growth in exactly the high-income countries whose networks are oldest. Two ageing curves, one physical and one human, are converging, and the authors contend that engineering asset management alone cannot capture what that convergence means.

The ISAG framework defines the gap as the mismatch between the ageing trajectory of water systems and the evolving needs, capacities and vulnerabilities of the populations those systems serve. The team identifies four interconnected pathways through which the gap emerges. The first concerns escalating demand for reliability: older residents, people with chronic illness and those with limited mobility are far more vulnerable to service interruptions, boil-water advisories and pressure losses. A single-day outage that is an inconvenience to a young, healthy household can become a medical emergency for a dialysis patient or an elderly person living alone. When the customer base ages, the same infrastructure failure produces disproportionately worse human outcomes.

The second pathway runs through the workforce. Water utilities face a well-documented retirement wave among operators, engineers and skilled tradespeople, which compounds the physical ageing of the assets themselves. The tacit knowledge needed to keep a fifty-year-old pumping station running often lives in the heads of workers approaching retirement themselves, and shrinking labour pools in shrinking regions make recruitment harder. The third pathway involves fiscal capacity. Communities with ageing populations often have contracting tax bases and rising social spending commitments, leaving less room for the capital investment that renewal demands. In Japan, where the Ministry of Land, Infrastructure, Transport and Tourism has documented widespread consolidation of small water utilities, the arithmetic of many elderly ratepayers supporting vast buried asset stocks has already become unsustainable for hundreds of small systems.

The fourth pathway is institutional and social: ageing populations can be less able to engage in the public processes, emergency preparations and adaptation planning that resilient water governance requires, and older neighbourhoods are often the ones served by the oldest mains and service lines. The authors organise these four pathways into what they describe as an infrastructure–society ageing decline spiral, in which deteriorating service quality drives out younger and more mobile residents, eroding the fiscal and workforce base still further and accelerating deterioration. Once that spiral takes hold, they argue, conventional repair cycles cannot keep pace, and the gap widens year after year.

To quantify the scale of the problem, the team draws on a broad body of official data: the American Society of Civil Engineers’ infrastructure assessments, Water UK’s economic analysis of asset maintenance and replacement, the Japanese ministry’s reform reviews, the US Army Corps of Engineers’ national levee database, the International Commission on Large Dams’ world register, OECD infrastructure investment outlooks, US Census Bureau demographic estimates and the UN’s world population prospects. A global dataset compiled by Zhang and Gu, published in Scientific Data, provides country-level indicators of infrastructure age. None of these sources alone links demography to infrastructure condition; that synthesis is precisely what the ISAG framework is meant to supply.

The proposal’s practical punchline is a pair of contrasting planning approaches. The first is demographic-blind investment, the status quo in most jurisdictions, in which renewal schedules are set purely by asset condition and risk scoring without reference to who lives downstream, downstream of the pipe, or behind the levee. The second is demographic-aware planning, in which intervention priorities, design standards and resilience investments are adjusted according to the age structure and projected demographic trajectory of the served population. Under the demographic-aware approach, an ageing service area would pull forward replacement of assets whose failure carries high public health consequences, justify higher redundancy in distribution networks serving vulnerable populations, and tilt investment toward measures such as backup power, pressure management and rapid response capacity.

The authors are careful to say the framework is a decision-support concept rather than a formula. Its value, they suggest, lies in making an invisible coupling visible: utilities that benchmark their asset age against demographic projections, and integrate social vulnerability data into risk models, will make different and better-targeted choices than those that do not. The framework spans the full infrastructure life cycle, from planning and design through operation, maintenance, rehabilitation and eventual decommissioning, and the authors argue that demographic ageing should be treated as a first-order design parameter on the same footing as hydrology, hydraulics and structural condition. That represents a significant cultural shift for a profession whose textbooks have historically treated the human population as a static demand number rather than a dynamic, ageing system in its own right.

The timing of the Comment is deliberate. It forms part of a series contributing to the 2026 UN Water Conference, supported by UNU-INWEH as part of the UN-Water initiative to ground water policymaking in evidence. With governments preparing national water security strategies and capital programmes running into the hundreds of billions of dollars, the authors hope the ISAG framing will find its way into regulatory guidance, utility asset management plans and international lending criteria. The stakes, they note, are not merely economic. A water system that fails its most vulnerable users fails everyone’s trust in it, and rebuilding that trust after crises is far more expensive than preventing them. The authors declare no competing interests, and correspondence for the work is handled through Tufts University’s Department of Civil and Environmental Engineering.

What the paper ultimately offers is a reframing: the water crisis of ageing infrastructure is also, unavoidably, a social and demographic crisis. Pipes and people are growing old together, and the institutions responsible for water must learn to plan for both at once. If the authors are right, the utilities, ministries and municipalities that internalise this coupling earliest will be the ones that keep taps running safely for the populations that depend on them most.

Subject of Research: A framework for integrating demographic ageing into water infrastructure planning

Article Title: To fix ageing water infrastructure, we must plan for an ageing population

Article References: Vahedifard, F., Azhar, M., Li, J., AghaKouchak, A., Brown, D. C., Marfeo, E., Null, S. E., Spearing, L. A., & Tajik, N. (2026). To fix ageing water infrastructure, we must plan for an ageing population. Nature Water, 4(9), 1062-1067. https://doi.org/10.1038/s44221-026-00711-z

Image Credits: AI Generated

DOI: 10.1038/s44221-026-00711-z

Keywords: ageing water infrastructure, infrastructure-society ageing gap, demographic ageing, water utilities, water governance, asset management, Nature Water, resilience planning, public health, UN Water Conference, vulnerable populations, infrastructure life cycle

The timing of the intervention is significant. The commentary forms part of a series of contributions to the 2026 UN Water Conference, supported by the United Nations University Institute for Water, Environment and Health as part of the UN-Water initiative to embed evidence-based policymaking in the water sector. As governments gather to negotiate responses to escalating water crises, Ong and Tortajada make the case that workforce transformation deserves the same political attention as pipes and plants. The authors acknowledge funding support from PUB, Singapore’s national water agency, an organisation frequently cited as a global benchmark for integrated water management and one that has invested heavily in developing specialised talent.

The pressures bearing down on urban water systems are well documented. Climate change is intensifying both floods and droughts, forcing utilities to manage extremes that legacy systems were never designed to withstand. Ageing infrastructure — much of it buried beneath city streets for half a century or more — is failing at rising rates, with pipe bursts, sewer overflows and treatment plant breakdowns imposing growing costs on operators and communities. Urban expansion adds another layer of stress, as informal settlements and fast-growing peri-urban districts often develop faster than formal water networks can reach them. Meanwhile, technological change is rewriting the skills profile of the sector entirely, as digitalisation, automation, remote sensing and artificial intelligence enter control rooms that were once run on manual gauges and experience-based judgement.

Each of these pressures translates into a human challenge. Consider the demographic problem first. Across many developed economies, the water workforce is ageing faster than the broader labour market, and retirements are outpacing recruitment. Studies cited in the commentary, including analysis by Brookings on renewing the water workforce in the United States, describe a widening pipeline gap: fewer young people enter water-related trades and professions than the sector needs to replace those leaving. The United States Environmental Protection Agency has repeatedly highlighted this workforce constraint alongside its funding programmes, including the water infrastructure investments announced under the bipartisan infrastructure law, which explicitly call for prioritising underserved communities. Money, the argument goes, cannot buy competence; somewhere between the appropriation of funds and the delivery of a resilient system stands a technician who must be trained, certified and retained.

The technological dimension of the workforce problem is equally consequential. Research published in Environmental Science & Technology by Garrido-Baserba and colleagues has examined how the digitalisation of wastewater operations changes decision-making in utilities, introducing data-driven control strategies that demand new competencies. The commentary extends this analysis to cybersecurity, an increasingly urgent concern as water and sewer infrastructure becomes networked. Work from Kompetenzzentrum Wasser Berlin on the future evolution of water infrastructure and associated cyber risks, together with industry analyses from GHD on overcoming vulnerabilities in critical water infrastructure, illustrates how digital transformation creates exposure that only a skilled, security-aware workforce can manage. A treatment plant that can be operated remotely can also, in principle, be attacked remotely — and the first line of defence is not software but the human expertise layered around it.

Different jurisdictions are already experimenting with different workforce models, and the commentary draws together these scattered examples into a coherent agenda. In the United States, the EPA maintains dedicated resources on the water infrastructure sector workforce, framing workforce development as integral to infrastructure sustainability. In Australia, the New South Wales Department of Climate Change, Energy, the Environment and Water has published a water industry traineeship guide designed to create structured entry pathways into the sector. New Zealand has gone further with a national competency framework maintained by Water New Zealand, which sets out the skills and standards expected of water professionals across the industry. In the United Kingdom, the sector skills body Energy & Utility Skills published a workforce renewal and skills strategy in 2020 anticipating demographic decline and skills shortages across energy and water utilities, while case studies such as Thames Water’s diversity and inclusion programme demonstrate attempts to widen the recruitment base.

Singapore offers perhaps the most comprehensive illustration of what deliberate workforce transformation looks like. PUB’s long-running innovation series documents how the city-state has paired infrastructure investment with sustained research and development capacity, cultivating in-house expertise in membrane technology, water reuse and integrated catchment management. The lesson, Ong and Tortajada suggest, is that technology adoption and workforce development are not parallel tracks but a single system: advanced treatment processes only deliver value when engineers understand them, operators can run them and managers can plan around them. UNESCO’s 2016 World Water Development Report, subtitled Water and Jobs, made a related macro-level argument nearly a decade ago — that water and employment are mutually reinforcing — but the commentary argues that this insight has still not been translated into routine workforce planning within urban utilities.

The health dimension of the workforce question also deserves emphasis. Research from New Zealand, published in the New Zealand Medical Journal by Chambers and colleagues, has examined drinking-water quality outcomes in ways that ultimately trace back to the competence of those operating supplies. When treatment fails, the public health consequences can be immediate and severe, as outbreaks of waterborne disease in various countries have demonstrated. This elevates workforce capability from a sectoral concern to a matter of public safety, comparable to aviation safety culture or medical training standards. Yet the water sector rarely enjoys the professional visibility of those industries, and the commentary argues that raising the status, pay and career prospects of water workers is therefore not merely an employment issue but a structural investment in public health and trust.

What, concretely, would a transformed urban water workforce look like? Drawing on the evidence assembled in the commentary, several elements emerge. Utilities and governments would treat workforce planning as a core function, mapping future skill needs against climate scenarios and digital roadmaps rather than filling vacancies reactively. Education and training pipelines would be formalised through apprenticeships, traineeships and competency frameworks of the kind already piloted in Australia, New Zealand and the United Kingdom. Recruitment would broaden beyond traditional engineering cohorts to include data scientists, cyber specialists and community engagement professionals, alongside deliberate efforts to diversify the workforce and include underrepresented groups. Retention would be addressed through career progression, fair compensation and professional recognition, countering the attrition that drains experienced operators into other industries. And international cooperation — the spirit of the 2026 UN Water Conference process — would help transfer these models to cities in lower-income countries, where workforce gaps are often most acute and where urbanisation is fastest.

The broader message of the commentary is one of reframing. Water security is usually measured in cubic metres, infrastructure asset registers and investment sums. Ong and Tortajada ask policymakers to add a different metric: does the city have enough people with the right skills to design, build, operate, secure and adapt its water systems under conditions of accelerating change? Their answer, informed by evidence spanning the United States, Europe, Australia, New Zealand and Singapore, is that most cities do not — and that this human deficit is quietly undermining decades of infrastructure investment. If the urban century is to be water-secure, they conclude, the transformation of the urban water workforce is not an optional complement to infrastructure spending but its essential foundation. The pipes, in other words, are only as resilient as the people who run them, and the time to invest in those people is now.

Subject of Research: The role of workforce transformation in supporting urban water security.

Article Title: Transforming the urban water workforce will support water security

Article References: Ong, C., & Tortajada, C. (2026). Transforming the urban water workforce will support water security. Nature Water. https://doi.org/10.1038/s44221-026-00708-8

Image Credits: AI Generated

DOI: 10.1038/s44221-026-00708-8

Keywords: urban water workforce, water security, water infrastructure, climate change, digitalisation, cybersecurity, workforce training, competency frameworks, urban water management, Nature Water, UN Water Conference, water utilities