Municipal Water Supply Research Articles

Analysis of Variability of Water Quality Indicators in the Municipality Water Supply System—A Case Study

This study investigated the variability of water quality indicators in four municipal water distribution systems near a medium-sized city. Despite the proximity of water intakes, water quality in different distribution systems can vary significantly due to local factors such as infrastructure conditions, treatment technology, and specific environmental conditions affecting water in each water supply network. Water samples were collected from multiple points in each system and analyzed for physicochemical properties. The results showed significant differences in total carbon, dissolved organic carbon, and ammonium nitrogen, indicating variability in water quality between systems. These results emphasize the need for integrated management strategies, innovative technologies, and real-time monitoring to maintain water quality. The study also highlights challenges such as aging infrastructure, pollution, and financial constraints in managing water supplies.

Hydropolitical processes in the conformation of the metropolitan municipal water system in Oaxaca de Juarez, Oaxaca, Mexico

El objetivo de esta investigación fue analizar el entramado político del sistema de abasto de agua de uso doméstico del municipio de Oaxaca de Juárez desde su fundación en 1523 hasta su conformación metropolitana actual. El estudio tiene por base la hidropolítica, bajo un enfoque en la captación, abastecimiento y control. La metodología cualitativa se apoyó en un análisis explicativo del manejo del agua municipal, sustentado en fuentes primarias, como archivos históricos, documentos oficiales y estadísticos, así como artículos e investigaciones académicas que aluden al proceso historiográfico del abastecimiento de agua. Se identificaron cinco procesos hidropolíticos clave: 1) el modelo monárquico de abasto frente a la perspectiva mesoamericana de uso (1523-1821); 2) la edificación hidráulica municipal (1755-1912); 3) legislaciones, acuerdos y conflictos intermunicipales (1821-1930); 4) conformación interurbana del sistema de agua municipal (1858-actualidad), y 5) metropolización del servicio de agua (1983-actualidad). Se concluye que el sistema de agua de Oaxaca y su edificación hidráulica se han desarrollado a partir de procesos incidentales de control en la subcuenca del río Atoyac-Oaxaca, generando conflictos, tensiones y arreglos que transgredieron la esfera municipal hasta conformar una entidad metropolitana del agua.

Water tariffs and social equity: Towards water service connections and pricing instruments for the poor

AbstractAside from operational sustainability and efficiency goals, water tariffs also need to address the requirements of affordability and equity, in most instances, by providing subsidies to poor households. Yet, poor households are unable to enjoy the benefits of such cross‐subsidization and linked conveniences as they are unable to get water service connections. Even with a well‐designed water tariff, the inability of poor households to get piped connections results in the payment of premiums for water that is difficult to access and, at times, of questionable quality. In this paper, we assess the pro‐poor projects of three Philippine municipal water systems and suggest that providing water service connections to poor households allows these households to avoid paying the water poverty premium, as well as experience the related public health and quality of life benefits accruing from such connections. We argue that designing the best tariff for existing socio‐economic, political, and environmental realities must go hand in hand with programs that provide water service connections to poor households as this will ensure not only operational viability but also equitable water provision.

Southern Bug River: water security and climate changes perspectives for post-war city of Mykolaiv, Ukraine

This article focuses on water security in Mykolaiv, a city of 0.5 million inhabitants in southern Ukraine, in the situation of scarcity of usable water resources caused by climate change and military operations. This problem arose after the Dnipro-Mykolaiv water pipeline was destroyed in April 2022 as a result of military operations and the supply of drinking water to the city was cut off. To ensure that the city’s population has constant access to sufficient water of acceptable quality, a search for alternative water sources and a climate risk assessment were carried out for the new municipal water supply system from the Southern Bug River. The possible change in flow and its intra-annual distribution under the influence of climate change was modeled using the WaterGAP2 hydrological model and climate projections under the SSP1-2.6 and SSP5-P8.5 scenarios. It was found that under the SSP1-2.6 scenario, the reduction in river flow will be insignificant (up to a maximum of 14% in the far future) and there will be no restrictions on the city’s water supply from this section of the river in the near (2021-2050) and far (2051-2080) period. The maximum water withdrawal for municipal water supply and the minimum environmental flow will reach their maximum value only in August (56% of the projected flow), which is not critical. Under the SSP5-8.5 scenario, in the long-term perspective of 2051-2080, the largest decrease in runoff will occur from May to October, and the water withdrawal will increase to 40-79% of the projected flow. The use of the research results not only in water management, but also in municipal administration, and their dissemination in territorial communities will contribute to the successful adaptation of socio-economic and environmental processes in the region and can bring successful benefits not only to the economy, but also to communities.

Norovirus outbreaks due to contaminated drinking water and probable person-to-person transmission, Kerala, India, 2021

BackgroundIn July 2021, the Alappuzha district in Kerala, India, reported an unexpected number of acute gastroenteritis (772) cases (Outbreak A). On October 10, 2021, a university in Wayanad, Kerala, reported 25 acute gastroenteritis cases (Outbreak B). We described both the outbreaks and determined the agent, source and risk factors. MethodsWe defined a suspected case as the occurrence of vomiting or at least three episodes of loose stools within 24hours and a confirmed case as those with stool samples/rectal swabs positive for norovirus. We did a matched case-control study in Outbreak A and a retrospective cohort study in Outbreak B. We calculated the adjusted odds ratio (aOR) in outbreak A, relative risk (aRR) in outbreak B and population attributable fraction (PAF). We tested stool and water samples for bacteria and viruses. ResultsWe identified Group II norovirus in stool samples in both outbreaks and 4/5 water samples in Outbreak A. Suspected norovirus infection was associated with drinking inadequately boiled water from the municipal water supply in outbreak A [aOR: 4.5; 95% C.I: 1.2-15.8; PAF: 0.23] and well water in hostels in outbreak B [aRR: 2.2; 95% C.I: 1.2-3.9; PAF: 0.15]. In Outbreak A, groundwater from tube wells was mixed in the municipal water supply overhead tanks without chlorination. ConclusionThe gastroenteritis outbreaks were caused by Group II norovirus due to the consumption of inadequately boiled contaminated groundwater (outbreak A) and well water (outbreak B). We recommended superchlorination of overhead tanks and wells and boiled water for drinking.

The Role of Antecedent Winter Soil Moisture Carryover on Spring Runoff Predictability in Snow-Influenced Western U.S. Catchments

Abstract Spring runoff is critical to agricultural, industrial, and municipal water supply as well as environmental uses in the western United States. Although spring runoff in this region has long been predicted based on late winter and early spring montane snow water storage, the role of soil moisture carryover from the previous winter is less understood and utilized in forecasts. We quantify the relationship between antecedent winter soil moisture and spring runoff for 85 unmanaged catchments in the western United States. Using a regression-based approach, we estimate the proportional reduction in error in seasonal runoff forecasts associated with soil moisture. We classify the catchments into two regimes: interior (cold and relatively dry) and maritime (warmer and wetter), based on seasonal variations in soil moisture. Soil moisture generally is relatively unchanged through the winter period in interior catchments, whereas it increases (mostly gradually, but occasionally rapidly) in maritime catchments. We find that winter temperature dominates soil moisture variability in both types of catchments. We find two patterns in the predictability of spring runoff. First, including antecedent winter soil moisture as a predictor enhances forecast accuracy and variance explanation in spring runoff for both interior and maritime catchments, particularly and with greater significance in interior catchments. Second, spring runoff prediction skill from antecedent winter soil moisture increases with elevation. Overall, we find strong evidence that the use of antecedent soil moisture can improve spring runoff forecast skill for catchments in the western United States. Significance Statement Spring runoff forecasts are crucial for water supply in the western United States, but typically exclude information about soil moisture despite its key role in the water balance. Our study explores how and why incorporating information about winter’s soil moisture levels affects spring runoff forecasts across 85 catchments in the western United States. We find that doing so can produce modest improvements in the prediction skill of spring runoff for both interior and maritime catchments but is particularly noticeable in interior catchments and at higher elevations where temperatures are lower. Overall, our research strongly supports the idea that using information about soil moisture from the previous winter can improve accuracy in spring runoff forecasts for the western United States.

Risk Factors Associated with Increased Toxoplasma gondii Seroprevalence in South Australian Sheep

Toxoplasma gondii (T. gondii) is a protozoan parasite of substantial impact to small ruminants, with reproductive failure a possible outcome of exposure. This observational study assessed T. gondii prevalence within the South Australian sheep population and investigated on-farm risk factors to T. gondii exposure via a cross-sectional survey. 1433 individual animals, consisting of 1282 mixed-age ewes and 151 mixed-age rams were blood sampled and serologically screened for T. gondii-specific antibodies. A risk-analysis questionnaire was conducted for each participating property. Of the 1433 animals sampled, 530 tested positive, with seroprevalence observed to be 39% (95% CI 28.7% to 49.3%) after accounting for clustering within properties. All properties returned at least one positive result, indicating a flock level seroprevalence of 100%. T. gondii seroprevalence was found to be higher in sheep on Kangaroo Island (46.6%; 95% CI 32.1% to 61.1%) compared to the South Australian mainland (31.3%; 95% CI 18.4% to 44.2%), however this difference was not statistically significant (P=0.125). A significant association was observed between T. gondii seroprevalence and age, with seroprevalence increasing from 30.2% (95% CI 17.7% to 42.6%) in one year old sheep, to 69.7% (95% CI 47.0% to 92.5%) in sheep older than six years (P=0.001). T. gondii seroprevalence was significantly higher in animals drinking water from surface water sources (55.9%; 95% CI 35.2% to 76.6%), compared to those exclusively sourcing reticulated mains water (19.1%; 95% CI 0%-39.0%) (P=0.028). An individual animal exposed to a surface water source was found to be more than ten times as likely to be exposed to T. gondii, than an animal sourcing only reticulated mains water (odds ratio:10.68; 95% CI 1.30 to 87.88). Water source is important in the transmission of T. gondii to South Australian sheep. Mitigation strategies should be developed and targeted at reducing contact between oocysts and water sources and reducing interaction between livestock and contaminated water.

A Transformer-Based Approach to Leakage Detection in Water Distribution Networks.

The efficient detection of leakages in water distribution networks (WDNs) is crucial to ensuring municipal water supply safety and improving urban operations. Traditionally, machine learning methods such as Convolutional Neural Networks (CNNs) and Autoencoders (AEs) have been used for leakage detection. However, these methods heavily rely on local pressure information and often fail to capture long-term dependencies in pressure series. In this paper, we propose a transformer-based model for detecting leakages in WDNs. The transformer incorporates an attention mechanism to learn data distributions and account for correlations between historical pressure data and data from the same time on different days, thereby emphasizing long-term dependencies in pressure series. Additionally, we apply pressure data normalization across each leakage scenario and concatenate position embeddings with pressure data in the transformer model to avoid feature misleading. The performance of the proposed method is evaluated by using detection accuracy and F1-score. The experimental studies conducted on simulated pressure datasets from three different WDNs demonstrate that the transformer-based model significantly outperforms traditional CNN methods.

A geospatial assessment of the resilience of municipal water supply to flooding in Nowshera District, Pakistan

Post-disaster functionality of the potable water supply infrastructure is crucial for maintaining public health and safety. The failure of the water supply system may harm inhabitants and significant users, which can impact other services and various types of infrastructures. It is vital to assess climate change impacts on water resources to ensure resilience and sustainable management. The study assessed the resilience of 22 municipal water schemes using an indicator-based framework, How Tough is Wash (HTIW), across six domains: environment, infrastructure, community governance, water supply management, supply chains, and institutional support. The sites of municipal water supply were purposively selected based on specific criteria to include those water supply schemes which have been directly affected by flooding or are vulnerable to the impact of the flood. The resilience scores ranged from (6 to 7.5) for schemes with very low resilience, (7.5 to 10.5) for those classified as poor, and (10.6 to 16.5) for schemes considered moderately resilient. It was discovered that protective measures against the risk of flood were negligible. Community engagement governance and water supply management needed to be stronger. Local governments can pinpoint current advantages and disadvantages by utilizing these metrics and their impact on the public water supply's resilience and strategically allocate resources for optimal outcomes. Furthermore, the metrics that have been suggested simplify and unify the multiple dimensions of the elements, enabling decision-makers to optimize the measures.

Constraining seasonal and spatial ambient and urban groundwater contributions to streamflow across a mixed land-use regional-scale Precambrian Shield watershed

Groundwater-surface water (GW-SW) interactions are complex phenomena that vary naturally over space and time and are being influenced by environmental change. The Whitson River watershed is a mixed land-use Precambrian shield watershed located in Northeastern Ontario, Canada in which groundwater is a source of municipal water supply and in which groundwater and surface waters are at risk of potential impacts from urban runoff, ongoing municipal drainage projects, periodic flooding, and climate change. This study used watershed-scale synoptic surveys of stable isotopes (δ18O and δ2H) and geochemistry, and corresponding mixing-model approaches (two-component and three-component) to quantify the seasonal and spatial variation in surface water, ambient, and urban groundwater contributions to streamflow. Multiple mixing models were generated based on isotope and geochemical source water identification, and the performance of these models was compared. Mixing-model analyses showed that groundwater contributes a critical, sustaining source to streamflow (> 50 % or more) during summer baseflow conditions, dropping to ∼ 15 % in fall when connection to shield lakes and wetlands dominate. Three-component mixing models showed similar results to the two-component models, refining groundwater contributions into ambient and urban groundwater sources. Estimated urban groundwater contributed 30 % or more to summer baseflow, dropping to ∼ 4 % in the fall. Baseflow estimates derived from graphical hydrograph separation were similar to mixing model groundwater estimates in the summer but suggest this approach overestimates groundwater contributions during the fall. These results demonstrate the complexity of source water contributions to streamflow and the challenges in their determination in mixed-land-use Precambrian Shield landscapes where communities are largely located. Assessment of source water contributions to streamflow across the Whitson River sub-watershed has generated a region-specific conceptualization (e.g. urban versus ambient groundwater) of a basin that is experiencing increased urban development, providing information that will be of value for long term management.

Integrated Geospatial and Geostatistical Multi-Criteria Evaluation of Urban Groundwater Quality Using Water Quality Indices

Groundwater contamination poses a severe public health risk in Lahore, Pakistan’s second-largest city, where over-exploited aquifers are the primary municipal and domestic water supply source. This study presents the first comprehensive district-wide assessment of groundwater quality across Lahore using an innovative integrated approach combining geographic information systems (GIS), multi-criteria decision analysis (MCDA), and water quality indexing techniques. The core objectives were to map the spatial distributions of critical pollutants like arsenic, model their impacts on overall potability, and evaluate targeted remediation scenarios. The analytic hierarchy process (AHP) methodology was applied to derive weights for the relative importance of diverse water quality parameters based on expert judgments. Arsenic received the highest priority weight (0.28), followed by total dissolved solids (0.22) and hardness (0.15), reflecting their significance as health hazards. Weighted overlay analysis in GIS delineated localized quality hotspots, unveiling severely degraded areas with very poor index values (>150) in urban industrial zones like Lahore Cantt, Model Town, and parts of Lahore City. This corroborates reports of unregulated industrial effluent discharges contributing to aquifer pollution. Prospective improvement scenarios projected that reducing heavy metals like arsenic by 30% could enhance quality indices by up to 20.71% in critically degraded localities like Shalimar. Simulating advanced multi-barrier water treatment processes showcased an over 95% potential reduction in arsenic levels, indicating the requirement for deploying advanced oxidation and filtration infrastructure aligned with local contaminant profiles. The integrated decision support tool enables the visualization of complex contamination patterns, evaluation of remediation options, and prioritizing risk-mitigation investments based on the spatial distribution of hazard exposures. This framework equips urban planners and utilities with critical insights for developing targeted groundwater quality restoration policies through strategic interventions encompassing treatment facilities, drainage infrastructure improvements, and pollutant discharge regulations. Its replicability across other regions allows for tackling widespread groundwater contamination challenges through robust data synthesis and quantitative scenario modeling capabilities.

Pricing drinking water testing in northern Haiti: Financial sensitivity to operating costs, user demand, and economic conditions

Safe drinking water availability is a concern in Haiti. Public systems have limited coverage and reliability. Private wells and local water sources are often of unknown or poor quality. Public health events, such as the 2010 cholera outbreak, demonstrate vulnerability to water contamination. To address these concerns, a drinking water laboratory was established at the Campus Henri Christophe in Limonade, a branch of the State University of Haiti, to meet water testing demands from local clients such as for-profit kiosks, institutions, industries, and municipal water systems. This study assessed the financial viability of a university-based drinking water laboratory in Haiti by calculating Internal Rate of Return and Net Present Value. Sensitivity analysis was used to identify the range of conditions under which laboratory revenues would cover operating costs. To achieve an acceptable profitability level, the laboratory must perform microbiological testing for routine monitoring samples and test an average of five samples per day. Price-based incentives for new clients have relatively small impacts on profitability. Finally, international and Haitian inflation cause some variation in profitability. These economic factors will be among the key drivers of laboratory operation costs. The results underscore the main factors that must be considered to make the laboratory successful and the importance of strategic marketing for laboratory managers to encourage clients to regularly test drinking water and emphasize microbiological testing.

Tracking suspended particulate organic matter biochemistry from glacial meltwater runoff to coastal waters of an Antarctic fjord

Increased glacier melting runoff in Antarctica involves intensification of freshwater, nutrients, sediments and organic matter inputs from land to the sea, which is impacting coastal ecosystems. Basic environmental characteristics of water and biochemical composition of suspended particulate organic matter (POM) both in the proglacial melting runoff system (PROGLARS) of Collins Glacier and marine surface waters of Collins Bay was studied based on organic biopolymers and molecular level analysis of amino acids (AAs), to discern among sources and degradation state in the two environments. Hierarchical Clustering Analysis revealed that PROGLARS stations and marine stations form two distinct groups in terms of water physicochemical characteristics and suspended POM biochemical composition. These differences are the consequence of low restricted contribution of freshwater from Collins Glacier runoff into the coastal-marine environment. Our results evidenced low concentrations of terrestrial suspended POM in marine waters of Collins Bay mainly attributed to low meltwater inputs between the 1st and 7th of February 2018. In terms of macromolecular composition, the predominance of proteins, denote the labile nature of suspended POM in the two environments. Suspended POM in Collins Bay is labile, poorly degraded, representing a protein supplemented food resource, with high energetic value and easily assimilated by heterotrophic marine organism. AAs composition supported less degraded suspended POM derived from marine phytoplankton in surface waters of Collins Bay, whereas, great degradation of suspended POM in the proglacial runoff system of Collins Glacier. Changes in the biochemistry of suspended POM caused by glacial melting and retreat, may affect food features and availability, the productivity of ecosystems, and ultimately, the capacity of Antarctic fjords to act as carbon sinks and climate regulators. Considering low influence of Collins Glacier meltwater in coastal marine waters of Collins Bay, due to the relatively slow retreat of Collins Glacier and low development of its meltwater runoff system, the results of our work are relevant as baseline information for comparison with other Antarctic fjords. Further knowledge about meltwater runoff and suspended POM input dynamics in Antarctic coastal ecosystems, is critical, particularly in areas prone to undergo increased glacier melting in the following decades.

The influence of water turbulence on surface deformations and the gas transfer rate across an air–water interface

We present experimental results of a study on oxygen transfer rates in a water channel facility with varying turbulence inflow conditions set by an active grid. We compare the change in gas transfer rate with different turbulence characteristics of the flow set by four different water channel and grid configurations. It was found that the change in gas transfer rate correlates best with the turbulence intensity in the vertical direction. The most turbulent cases increased the gas transfer rate by 30% compared to the low turbulence reference case. Between the two most turbulent cases studied here, the streamwise turbulence and largest length scales in the flow change, while the gas transfer rate is relatively unchanged. In contrast, for the two less turbulent cases where the magnitude of the fluctuations normal to the free surface are also smaller, the gas transfer rate is significantly reduced. Since the air–water interface plays an important role in the gas transfer process, special attention is given to the free-surface deformations. Despite taking measures to minimise it, the active grid also leaves a direct imprint on the free surface, and the majority of the waves on the surface originate from the grid itself. Surface deformations were, however, ruled out as a main driver for the increase in gas transfer because the increase in surface area is < 0.25%, which is two orders of magnitude smaller than the measured change in the gas transfer rate.

Assessing the impact of socio-demographic factors on municipal water security in planned and unplanned urban centers of Pakistan

ABSTRACT In the current era of climate change, along with population and urbanization growth, Pakistan is facing increasing environmental challenges. These challenges intensified the pressure on the existing municipal water supply (MWS), which necessitated a need for a comprehensive assessment of the municipal water dynamics in these three cities. This research aimed sixfold: assessing the current municipal water services, municipal water demand, groundwater table depletion, satisfaction, awareness level, and the monetary indicators of the MWS. A three-stage key performance indicator (KPI) -based questionnaire survey was conducted, both online and through a field survey, self-administered between March 2022 and December 2023 in Islamabad (planned), Rawalpindi, and Mardan (unplanned). Public water supply (PWS) coverage remained 63% in Islamabad and 52% in Rawalpindi, while Mardan heavily relied on (44%) bore wells. Similarly, water scarcity remained alarmingly high in Islamabad (82%) and Rawalpindi (72%), compared to (relatively) low in Mardan (16%) between June and August every year. Over the past three decades, groundwater depths (GWD) in Rawalpindi have increased up to 300 ft, in Islamabad by 200 ft, and in Mardan by 50 ft. The study calls for intensified roles of all stakeholders, including the community, municipalities, policymakers, and urban planners, to ensure sustained municipal water supply.

Filling Discrepancies between Consumer Perception and Actual Piped Water Quality to Promote the Potable Use of the Municipal Water Supply in Indonesia

Although piped water is a safely managed water source, many people prefer drinking packaged/bottled water, which undermines environmental sustainability by creating waste plastics. Thus, to encourage drinking tap water, this study aimed to identify and fill the discrepancy between consumers’ perception of and the actual quality of the municipal water supply in Indonesia. Through questionnaire surveys in three cities, i.e., Malang, Bogor, and Semarang cities, we found that the majority of the residents, namely, 82%, 58%, and 66%, respectively, drank packaged water. Although the piped water supply from Perusahaan Daerah Air Minum (PDAM) has a good appearance, color, taste, and water quality, sporadic microbial contamination was detected due to the depletion of residual chlorine. However, packaged water was also contaminated by indicator bacteria owing to storage methods. There was a notable discrepancy between the residents’ perceptions of tap water safety and their choices of drinking water sources. The residents perceived spring water as a clean source, which influenced their selection of water sources more than the costs of water. Public drinking stations installed by PDAM helped to win consumers’ trust in PDAM water, indicating that installing more public drinking stations will encourage more people to drink piped water.

Exploring the Antimicrobial Resistance Profile of Salmonella typhi and Its Clinical Burden.

Background: Typhoid fever caused by Salmonella enterica serovar Typhi (S. typhi) continues to pose a significant risk to public health in developing countries, including Pakistan. This study investigated the epidemiological factors linked to suspected and confirmed S. typhi infections in Peshawar's hospital population. Methodology: A total of 5735 blood samples of patients with suspected enteric fever were collected from September 2022 to November 2023. S. typhi infection was confirmed using microbiological culture of blood samples, biochemical-based tests, and DNA-sequencing methods. Drug sensitivity testing on cultures was conducted as per the CLSI guidelines. Chi-square tests were used to analyze the clinical and epidemiologic characteristics of 5735 samples stratified by S. typhi infection status, and risk factors were assessed by applying logistic regression models to estimate odds ratios (ORs). Results: The number of confirmed typhoid fever cases in this hospital-based study population was 691 (/5735, 12.0%), more prevalent in males (447/3235 13.8%) and children (0-11 years) (429/2747, 15.6%). Compared to children, the risk of S. typhi infection was lower in adolescence (adjusted OR = 0.52; 95% CI: 0.42-0.66), adulthood (19-59 years; aOR = 0.30; 95% CI: 0.25-0.38), and older adulthood (aOR = 0.08; 95% CI: 0.04-0.18) (p < 0.001). Compared to males, the risk of S. typhi infection was lower in females (aOR = 0.67; 95% CI = 0.56-0.80; p = 0.002). Living in a rural residence (compared to urban) was associated with a higher risk of infection (aOR = 1.38; 95% CI: 1.16-1.63; p = 0.001), while access to a groundwater source (compared to municipal water supply) led to a lower risk (aOR = 0.56; 95% CI: 0.43-0.73; p = 0.002). Vaccination demonstrated a robust protective effect (aOR = 0.069; 95% CI = 0.04-0.11, p = 0.002). For those with typhoid infections, clinical biomarker analysis revealed the presence of leucopenia (65/691, 9.4%), thrombocytopenia (130/691, 18.8%), and elevated alanine aminotransferase (ALT) (402/691, 58.2%) and C-reactive protein (CRP) (690/691, 99.9%) levels. Worryingly, among the positive S. typhi isolates, there was a high prevalence of drug resistance (653/691), including multidrug-resistant (MDR 82/691, 11.9%) and extensively drug-resistant types (XDR, 571/691, 82.6%). Conclusions: This study highlights the importance of age, sex, locality, water source, and vaccination status in shaping the epidemiological landscape of S. typhi in the Peshawar district. It implies that expanding vaccination coverage to the broader population of Khyber Pakhtunkhwa province, particularly in the district of Peshawar, would be beneficial.

A deep learning-based model for estimating pollution fluxes from rivers into the sea and its optimization

Pollution fluxes from rivers into the sea are currently the main source of pollutants in nearshore areas. Based on the source-sink process of the basin-estuary-coastal waters system, the pollution fluxes into the sea and their spatiotemporal heterogeneity were estimated. A deep learning-based model was established to simplify the estimation of pollution fluxes into the sea, with socio-economic drivers and meteorological data as input variables. A method for estimating the contribution rate of pollution fluxes from different spatial gradient was proposed. In this study, we found that (1) the pollution fluxes into the sea of total nitrogen (TN) and total phosphorus (TP) from the Bohai Sea Rim Basin (BSRB) in 1980, 1990, 2000, 2010, and 2020 were 25.38 × 104, 26.12 × 104, 27.27 × 104, 29.82 × 104, 25.31 × 104 and 1.32 × 104, 2.14 × 104, 2.09 × 104, 1.87 × 104, 1.68 × 104 tons, respectively. (2) The proportion of rural life and livestock to the TN was the highest, accounting for 39.18 % and 21.19 %, respectively. The proportion of livestock to the TP was the highest, accounting for 39.20 %, followed by rural life, accounting for 24.72 %. The results indicated that the pollution fluxes in the BSRB were related to human economic activities and relevant environmental protection measures. (3) The deep learning-based model established to estimate runoff pollution fluxes into the sea had the accuracy of over 90 %. (4) As for contribution rate, in terms of the elevation, the range of 0–100 m had the highest proportion, accounting for 39.65 %. The range of 50–100 km from the coastline had the highest proportion, accounting for 18.11 %. In terms of the district, coastal area has the highest proportion, accounting for 38.00 %. This study revealed the changing trends and driving mechanisms of pollution fluxes into the sea over the past 40 years and established a simplified deep learning-based model for estimating pollution fluxes into the sea. Then, we identified regions with high pollution contribution rate. The results can provide scientific references for the adaptive management of the nearshore areas based on the ecosystem.

Assessing Public Water Management Efficiency in North-western Mexico with a Two-stage Bootstrap Data Envelopment Analysis Model

Purpose: Mexico faces severe water availability problems, resulting in higher stress on its distribution in many states. To resolve the increasing water demand, it is essential to evaluate public water management to ensure the success of any decision-making policies to decrease the water pressure in the country. Methodology/Approach: For water management systems, benchmarking their performance relative to others can be an appropriate way to identify possible improvements. Using data from the National Census for drinking water and sanitation in 109 municipalities in the northwest region of Mexico, this analysis aims to evaluate the water management efficiency based on a two-stage Bootstrap Data Envelopment Analysis model with intermediate variables. Findings: The study found average efficiency in water system management but very low efficiency in system improvements. Additionally, no relationship was identified between the two stages or population size and density. Research Limitation/Implication: The study highlights the need for transparent water policies to address the country's shortage. Adjusting municipal public water system management operations and designing future strategic planning is essential. Originality/Value of paper: The presented analysis investigates a relationship between water management and water system improvements.

ОБЛАДНАННЯ ВХІДНОЇ МАГНІТНО-КАВІТАЦІЙНОЇ ПІДГОТОВКИ ВОДИ ДЛЯ ТЕПЛОМЕРЕЖ

If high-quality water treatment for boilers is not organized, the impurities present in untreated water lead to a number of problems: large colloidal and mechanical impurities in the form of scale, rust, clay or sand quickly clog the pipes, significantly reducing their internal diameter. This causes the failure of shut-off valves and pumping equipment: hardness salts and other poorly soluble salts (carbonates, magnesium and calcium sulfates, silicates, various compounds of copper and manganese) settle, creating a crust on the metal walls of the equipment, which reduces its heat output. This contributes to a reduction in boiler power, increases energy costs, and significantly shortens the life of the equipment. Based on the analysis of the latest research, it is proposed to improve the quality and composition of water that comes from municipal water supply, artesian wells and reservoirs, before filtering and deaerating water, it is proposed to pre-treat it with hydrocavitation and a magnetic field in order to soften and change its properties. The essence of the operation of the proposed equipment is that the effect of sound hydrocavitation and a variable magnetic field on water is reduced to a single process - the splitting of water molecules in the cavitation cavity into active radicals. The essence of various processes, namely hydrocavitation and magnetic influence on the passage of chemical reactions, breaking of hydrogen bonds in water molecules, is considered. The design of the equipment for the incoming magnetic cavitation preparation of water with an additional hydrocavitation effect on water during the reciprocating movement of the liquid through the nozzle is proposed, which combines the effects of breaking hydrogen bonds in water molecules, oxidation of iron and calcium ions, increasing the Рn indicator, and after its after settling, it is fed to the ion exchange and deaeration units, and later to the heating mains.