What do we know about innovation in water governance?

Abstract

Water governance faces compounding pressures from climate variability, ageing infrastructure, and rising demand for environmental performance. The knowledge base that informs governance responses, the body of expertise that policy instruments mobilise, has not been mapped systematically across decades. The object of analysis here is precisely that knowledge base, not policy capacity itself: we characterise the body of scientific and engineering expertise on which governance choices can draw. We analyse 11 186 peer-reviewed articles indexed in Web of Science (1980–2024) drawn from six structured queries covering treatment, recharge, contaminant control, biological reactors, resource recovery, and sensing methods. Latent Dirichlet Allocation identifies six thematic streams; Hirschman-Herfindahl and Revealed Technological Advantage indices trace concentration over time and national specialisation. Treatment-process engineering remains the mainstream, but the field has diversified since 2018, with contaminant control and sensing-and-detection methods growing fastest, while resource-recovery knowledge, the core of the circular-economy transition, grows slowest and loses share. National portfolios track regulatory context and hydrological exposure. The paper provides a full field-level cartography that complements extant frameworks and shows that the knowledge base for circular water governance is broadening, while the institutional toolkit for steering the transition remains incomplete.