In low-resource settings, drinking-water safety decisions are frequently shaped by subjective perceptions rather than objective contamination data, yet this correspondence is poorly characterized. This cross-sectional study (n = 425) in Nadowli-Kaleo District, Upper West Region, Ghana examined concordance between perceived drinking-water quality and field-observed sanitary contamination risk, together with socioeconomic determinants of risk appraisal calibration. Perceived quality was rated on a 1–5 Likert scale; field-observed sanitary contamination risk was aggregated into a 0–4 ordinal risk index from a structured observation checklist (a proxy for, not a direct microbiological measure of, water quality), reverse-scaled, with perceptions classified as calibrated when |gap| ≤ 0.5. Perceived quality was strongly and inversely associated with observed contamination risk (Spearman’s ρ = −0.780; p < 0.001), indicating that household perceptions tracked broad contamination-risk gradients well. However, agreement at the individual household level was weaker: only 49.4% of households met the calibration criterion (mean gap = −0.86) under our primary threshold, and this proportion was sensitive to the threshold chosen (ranging from 26.1% at ±0.3 to 63.1% at ±1.0). Educational attainment showed no reliable association with calibration accuracy (no formal education 55.5%; secondary 44.1%; postgraduate 12.5%, n = 8; Pearson χ²(4) = 7.24, p = 0.124), and a quadratic logistic model provided no evidence of a non-linear (inverted-U) relationship (quadratic OR = 0.94; p = 0.462); income and residence duration were likewise not significant predictors. These findings suggest that perception-based metrics alone may be insufficient for individual-level risk assessment, and that common socioeconomic proxies do not reliably identify well-calibrated households, calling for objective monitoring and tailored risk communication to advance SDG 6.
Groundwater monitoring is essential to sustainable water resource management and climate resilience strategies – a source of key data to support decision-making. However, in many regions of the world including in Malawi, a country that is heavily reliant on groundwater, the scarcity of groundwater monitoring data is a persistent challenge. The scarcity of data is compounded by the in-operation of existing groundwater monitoring networks. While operational challenges have often been framed as a technical or financial issue, this study applies a co-creation methodology to explore the wider institutional, procedural, and social factors contributing to persistent data scarcity. Drawing from sourced grey literature and a series of participatory workshops held in Malawi with stakeholders from across the water sector, including community representatives, several systemic and interconnected challenges were identified. Themes of challenges include institutional and governance fragmentation, procedural ambiguity, limited and uncertain financing, and a lack of formalised community engagement. Participants emphasised that these challenges are not independent and addressing them in isolation is unlikely to lead to long-term improvement in data availability. Instead, data scarcity is a symptom of deeper systemic issues, and any attempt to improve the monitoring network must consider the broader context in which it operates. The findings suggest that future efforts, in Malawi and in other global contexts, should prioritise adaptive and inclusive strategies, including strengthened institutional coordination, updated procedural guidance, and an expanded role for community participation in monitoring activities.
Increasing wildfire activity poses a threat to water resources via the mobilization of hazardous materials such as arsenic (As). While As contamination of water resources is well studied, the fate and transport of As impacted by wildfire are not well characterized. This literature review synthesizes studies addressing the questions of: (1) Does fuel type influence how As is mobilized by wildfire?; (2) What mobilization pathways are most common for As when impacted by wildfires?; and (3) How are surface and groundwater As concentrations impacted by wildfire mobilization of As? To address this goal, articles were queried using Boolean search strings in Google Scholar, PubMed, and Web of Science and screened for relevance using PECO (Population, Exposure, Comparator, and Outcome) criteria. Twenty articles met the criteria, showing wildfire mobilization of As and changes in concentrations or loading of As to surface or groundwater. The majority of studies (16 of 20) showed an increase or a likely increase in As in waterbodies post-wildfire. Runoff to surface water was by far the dominant pathway. Average values typically did not exceed drinking water standards, although six studies reported instances where this occurred, with one reporting exceedances in treated drinking water itself. The largest value of dissolved As reported across surveyed literature (70 µg/L) was measured downgradient of a legacy mining operation post-wildfire. Higher values were also observed downstream of burned agricultural or urban areas, illustrating how human activities concentrate As, which can then be subsequently mobilized by wildfire. In contrast to surface water, groundwater impacts were inconsistent in the limited literature, with one study showing an increase in post-wildfire As, while the other two studies showed no-change. Overall, these results suggest communities may need to test drinking water supplies for As following wildfire, especially in cases where mining, agricultural, or urbanized areas are burned.
Public bathrooms are a critical yet underexamined component of urban health infrastructure in the United States. Despite their importance for hygiene, dignity, and social participation, their availability and quality remain poorly documented. As public bathroom availability declines, private bathrooms like those in businesses are increasingly serving as de facto “public” options, raising questions about equity and accessibility. This study examined the availability, accessibility, and characteristics of traditional (government funded) and de facto public bathrooms (privately funded) in Atlanta, Georgia. We conducted systematic audits of bathrooms across 15 areas in Atlanta. Women’s, men’s, gender-neutral, and family/caregiving bathrooms were assessed using 32 location- and 86 bathroom-specific criteria. Descriptive statistics were calculated to summarize characteristics and density of bathrooms per square kilometer. Regression models were used to compare characteristics of government-funded and privately funded facilities. Of 262 identified locations, 55.3% were inaccessible due to lack of a publicly accessible bathroom, locked doors, or being fully occupied for more than 10 minutes. Across 117 accessible locations, 207 bathrooms were audited; 58.9% of which were privately funded. Overall facility density was 18.2 per square kilometer, with wide variation (range: 2.55-76.4). Government-funded bathrooms had a larger quantity of functional toilets, urinals, and sinks, whereas privately funded facilities were more likely to be single-occupancy and allow use without first requiring access via gate or turnstile. Findings reveal spatial inequities in public bathroom access across Atlanta and a reliance on private infrastructure to meet public needs, underscoring uneven urban sanitation provisions as a feature of the city’s built environment.
The contemporary scientific concept of the hydrological cycle emerged within a positivist paradigm, historically serving the interests of state-led development and colonial expansion. This legacy positioned water primarily as a resource to be measured, extracted, and controlled – an ontology that has contributed, directly and indirectly, to the planetary crises of climate change and environmental degradation. While sociohydrology has advanced the field by including human and cultural dimensions, it remains largely rooted in positivist onto-epistemology that separate humans from nature. To achieve a sustainable and just coexistence on a living planet, we critically examine the colonial foundations of hydrological knowledge and embrace onto-epistemological pluralism, as a more transformative concept toward equitable relationships with and benefit from water. Drawing from place-based onto-epistemologies and their practices of ancestral hydro-technologies, we propose new ways to re-imagine our understanding of hydrology based on an onto-epistemological pluralism, incorporating multiple values, cultural norms, and identities. With this work, we launch an open reflection to pluralize narratives and corresponding illustrative archetypes of how human-water feedback are conceived, portrayed and known. The goal of this discussion is to develop the foundation for co-creating a more suitable concept of the sociohydrological cycle, which builds on a plurality of ways of understanding and relating to water.
Low-cost, scalable tests hold great potential to increase the availability of water safety data globally, especially in resource-limited settings. We evaluated the Lishtot TestDrop Pro, a commercially available, low-cost triboelectric-based sensor marketed for real-time determination of water contamination, including microbiological safety. We prepared a total of 199 water samples by serial dilution of raw wastewater influent into deionized water to produce a range of E. coli counts from <1 to too numerous to count (TNTC, > 300 per dilution plate) CFU/100 mL to evaluate the sensor. We tested these waters using the manufacturer’s instructions. We collected sensor readings using three settings on each of five devices, generating nearly 8,955 individual measurements to compare against E. coli measured via standard membrane filtration assays (EPA Method 1604), a common metric of drinking water safety. We found no statistical correlation between the sensor score and E. coli presence in water: 43% of sensor readings indicated “safe” when wastewater and E. coli was present, and 56% of samples lacking E. coli were deemed “unsafe” by the sensor when wastewater was absent. The Lishtot TestDrop Pro is not an accurate method for measuring microbiological water safety.
Extreme weather events, e.g., droughts, floods, heatwaves, freezes, increasingly challenge physical, financial, and social infrastructure as population and economic growth increase exposure and vulnerability. We propose supplementing conventional disaster risk management strategies with Weather Jiu-Jitsu, an approach that leverages the chaotic dynamics of weather systems to redirect or dissipate destructive trajectories through targeted, low-energy perturbations. Coupled with deep learning models, this framework could serve as a form of nature-assisted global infrastructure to reduce catastrophic climate-extreme impacts in the 21st century. We demonstrate the potential of this strategy through successful perturbation experiments applied to tropical cyclones, atmospheric rivers, freezes, and other high-impact events.
Decentralised wastewater treatment and reuse systems (DWTRS), supported by an enabling governance framework, offer an innovative circular water management solution to the escalating urban water crisis. Bengaluru, one of India’s fast-growing megacities, has emerged as a pioneer in implementing DWTRS at scale, making it a unique case globally. This study examines how the shifts towards decentralisation and circularity have transformed (waste)water policies and practices in Bengaluru, by combining a water reuse value chain conceptualisation with an analysis of the emerging DWTRS governance architecture. The analyses are based on a mixed-methods approach, including policy analysis, stakeholder interviews, quantitative estimation, and site visits. It is estimated that approximately 25% to 60% of the total wastewater generated in the megacity could potentially be reused for various non-potable purposes, both onsite and offsite. The mapping of policy shifts at the city, state, and national levels revealed the key actors and drivers of the water reuse agenda. National policies have driven this shift towards DWTRS in response to growing water contamination and have also set overarching visions and standards that states adopted through top-down processes. Policies of the Karnataka State, combined with judicial intervention and civil society advocacy, led to stricter regulations on wastewater reuse, discharge, and monitoring. Despite a progressive policy vision, DWTRS implementation and scaling is hindered by fragmented regulations, monitoring gaps, and the absence of reuse standards, among other issues. Realising the full potential of DWTRS requires reforms towards a comprehensive multi-level governance framework across the entire reuse value chain that supports a holistic approach to urban water management. These findings contribute to the design of an enabling governance framework for DWTRS and the enhancement of water security in Bengaluru, offering valuable insights for other rapidly urbanising regions with similar water-related challenges.
Rapid urbanization and climate variability in Addis Ababa's steeply sloped watersheds-characterized by poorly draining Vertisol soils and high impervious cover-have increasingly overwhelmed stormwater infrastructure, resulting in frequent flooding and erosion. To address the lack of systematic performance data, this study conducted a systematic performance evaluation of 30 representative stormwater infrastructure units across five spatially delineated blocks within a 30-hectare urban micro-watershed in Addis Ababa, Ethiopia. The objective was to develop an evidence-based framework for prioritizing maintenance and green infrastructure (GI) retrofitting interventions. Six critical performance criteria-flood conveyance capacity, structural integrity, erosion control effectiveness, sediment accumulation, maintenance accessibility, and flood control effectiveness (from hydrologic modeling)-were assessed through structured field inspections and Personal Computer Storm Water Management Model (PCSWMM) simulations. The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), integrated with expert-derived weights from the Analytic Hierarchy Process (AHP), was applied to rank the five blocks. A comprehensive sensitivity analysis tested ranking robustness against five alternative weighting scenarios. Results showed that sediment accumulation and flood conveyance capacity emerged as the most influential criteria. Spearman's rank correlation coefficients exceeded 0.92 in all cases, confirming strong ranking stability. Block 3 achieved the highest performance score (C-i = 0.7), while Block 4 ranked lowest (C-i = 0.43) due to structural deficiencies and sediment buildup. The analysis revealed that 42.3% of the study area is ready for GI retrofitting, while 57.7% requires prioritized maintenance and rehabilitation. The TOPSIS-AHP-PCSWMM framework provided a transparent, evidence-based mechanism for prioritizing interventions, offering practical insights for optimizing stormwater management in Addis Ababa and comparable data-scarce urban environments in the Global South. This work supports the United Nations Sustainable Development Goals (UN-SDGs) 11 (Sustainable Cities), 12 (Responsible Consumption), and 13 (Climate Action).
Analyzing surface-water PFAS datasets using EPA Method 1633 often yields many results below reporting limits and fewer qualified low-level detections, making post-processing choices important for site comparisons. In this pilot study, we used a single synoptic survey of 10 sites in Trinity River headwater tributaries near Fort Worth, Texas, to demonstrate a transparent workflow for summarizing such data. Samples were collected on 21 December 2025 and analyzed for 40 target PFAS using isotope-dilution LC-MS/MS at a commercial laboratory accredited to ISO/IEC 17025. Of the 400 site-analyte results, 82 (20.5%) were detected, and 318 (79.5%) were left-censored. We distinguished detect-only Sigma PFAS40, defined as the sum of quantified detections, with non-detects set to zero, from median-imputed Sigma PFAS40, a model-based total generated using 5,000 censoring-aware imputations per site. Median imputed Sigma PFAS40 ranged from 55.5 to 685.2 ng/L. One high-total site (TW08; 95% conditional imputation-uncertainty interval: 673.2-696.8 ng/L) clearly exceeded the other nine sites. Imputation increased Sigma PFAS40 by 32-38 ng/L at lower-total sites relative to detect-only sums, demonstrating that non-detect handling materially affects low-end site comparison. Site rankings were stable across distributional assumptions, substitution methods, and qualifier reclassification. River-network distance, catchment land-cover metrics, and multi-year national pollutant discharge records were retained only as screening-level context. Overall, this pilot case study shows that the main value of the dataset lies in a reproducible, qualifier-transparent, and censoring-aware workflow for PFAS reconnaissance, rather than in any definitive assessment of temporal conditions or causal source attribution.
The water-energy-food (WEF and its variants) nexus addresses the intricate linkages between human and natural systems to ensure sustainable management of natural resources without compromising economic, social, and environmental well-being. Despite this, the WEF nexus has been mainly approached as a focused biophysical system connecting those three dimensions. This review maps the extent to which the WEF nexus has been conceptualised and the consideration of additional dimensions linked to environmental and social outcomes. The aim is to broaden the WEF nexus concept to enhance its applicability to human, planetary, and sustainable development outcomes. Of the identified nexus frameworks, approximately 50% are sectorally unbalanced, as they centralise one or more resource node(s). Water and energy are key nexus nodes in most frameworks. The second most popular framing is water-energy-food-climate, followed by water-energy-land (WEL) and water-energy-food-land-ecosystems. In addition, the current WEF nexus approach is biased towards input-oriented conceptualisation. It fails to make explicit linkages to outcome- and impact-based dimensions, such as politics, gender, environment, planetary health and the economy. This limits its relevance and practical application in decision-making and policymaking for addressing sustainability and developmental challenges. Models and tools should be improved to be more holistic, including WEF resources and other linked resources, and should be useful for monitoring all sustainability outcomes (economic, social, and environmental). We propose a conceptual broadening of the WEF nexus to a WEF+ nexus, with the “plus” representing added outcomes-based dimensions such as environment, climate, people, planet and health. This conceptual broadening balances WEF resource securities with human, planetary and sustainable development outcomes.
Datacenters are powering the Artificial Intelligence (AI) revolution. However, their water insecurity risks remain neglected. Limited research on the matter quantifies water demand at national or watershed-scales and estimates water use associated with training and using AI models. Research fails to examine water insecurity concerns held by households and communities where datacenters are planned or are operational. This article identifies four water insecurity concerns in the U.S. by synthesizing public reporting and legal filings involving non-governmental organizations, citizen coalition groups, investigative reporters, and individual citizens. These concerns include how datacenters’ development and operation can (i) undermine the democratization of water governance; (ii) contribute to unsustainable water use and rising utility costs; (iii) reduce the flexibility and resilience of water use decision-making; and (iv) increase water use across scales as a result of rising electricity demand. Three areas for future research are identified from the cases reviewed. First, local governments and utilities do not always readily provide water use data associated with datacenter operations; hence, public records should be requested and shared to democratize decision-making. Second, water-related risks posed to public health, rural and land-based livelihoods, and ecosystems from datacenter operations require context-specific empirical investigation. Third, examining whether and how specific water governance arrangements can engender acute health, economic, and environmental risks, especially under extreme events such as heatwaves or droughts, requires institutional analyses. Overall, analyzing datacenters’ volumetric water use within local contexts offers a more relevant analysis of water insecurity concerns and experiences.
Biodiversity loss and conservation are increasingly coming into focus in global policy fora, requiring information and assessments at wider spatial and temporal scales than previously considered. However, the monitoring framework required to support such data collection and assessment is lacking in many countries and is not harmonized across countries, hampering these efforts. Aggregation of existing freshwater data offers a solution to the problem of assessing status and trends of ecosystems and biodiversity at large spatial scales in the absence of nationally coordinated monitoring efforts. Analysis of aggregated data from different sources, collected using different protocols and with varying levels of metadata and supporting data, can be challenging and requires decisions regarding data comparability. In this paper, we identify the challenges inherent in harmonizing aggregated freshwater data for analysis, including general concerns related to research goals, spatial and temporal scale, sample selection, sampling effort, and site integrity. We also discuss the challenges related to measured parameters, sampled habitats, sample collection and processing methods, and data integrity for phytoplankton, benthic algae, macrophytes, zooplankton, benthic macroinvertebrates, fish, and supporting variables such as water and sediment chemistry. We provide a workflow to evaluate each of these challenges and make decisions about how best to work with the data. Finally, we review a case study from a large-scale analysis of freshwater data from the circumpolar Arctic region that exemplifies the encountered challenges and the chosen solutions. Through the description of the case study, we provide practical solutions to support aggregation and analysis of existing freshwater data. As global conversations about biodiversity status and trends continue, the demand for large-scale analyses of data from different sources will only grow. In the absence of globally harmonized monitoring, we are faced with the need to ensure comparability of data, making expert judgements where needed to support sound conclusions.
Recent high-profile crises have disrupted the myth of universal access to potable water and sanitation in the United States. According to the Joint Monitoring Project on access to Water, Sanitation, and Hygiene (JMP), more than 99% of the population have unfettered access to water services [1]. Reports and scholarly papers, however, show higher numbers lacking potable water and/or sanitation services – specifically in places with high percentages of historically marginalized populations. Mainstream media, politicians, and agency functionaries generally voice support for addressing the issue. Still, sustainable programs, policy development, and activism have been hampered by a lack of data that accurately depicts the problem. In this essay we analyze the currently available data collection systems estimating water, sanitation, and hygiene (WaSH) access in the United States – in databases located across multiple government agencies to measure different policy objectives, and at different temporal and geographic scales. This leads to rather disparate estimates of the scope and magnitude of the problem and creates an information landscape that is difficult to navigate for those focused on improving conditions. We discuss new initiatives (specifically portals and dashboards) that aim to improve data availability, accuracy, and visualization to drive better policies, programs, and actions toward closing the WaSH gap in the United States. These are important steps for improving data about access to potable water and functional sanitation.
