Evaluating water, sanitation, and hygiene in schools of Bangladesh: progress toward SDG compliance

The sustainable goal (SDG) 6 aims to achieve universal access to safe drinking water (SDG 6.1) and sanitation and hygiene (SDG 6.2) for all by 2030 (United Nations 2024). Globally, the lack of access to adequate water supply and sanitation facilities poses significant challenges and health risks (Nawaz et al. 2023). Approximately 2 billion people lack adequate water supplies, and around 3.6 billion lack proper sanitation facilities (UNESCO 2023). Unsafe water, inadequate sanitation, and poor hygiene practices contribute to roughly 88% of diarrheal deaths worldwide (Getahun & Adane 2021). Moreover, SDG 4 (Quality Education) includes water, sanitation, and hygiene (WASH) facilities among others in school (4.a) as a crucial element of a safe, inclusive, gender-sensitive, and effective learning environment (UNICEF and WHO 2018). The global initiative also intends to provide WASH facilities, including schools, to achieve SDG 6 by 2030 (United Nations 2024).

WASH facilities in schools are recognized as crucial factors for maintaining good health, improving education opportunities, preserving dignity, particularly for girls, and decreasing the potential of disease transmission (UNICEF and WHO 2018, 2022) among schoolchildren. The absence of WASH facilities in schools makes students vulnerable to water-related illnesses such as diarrhea, cholera, and typhoid, which impair learning abilities, increase absenteeism, and may lead early to school dropout (Islam et al. 2015). Moreover, educational institutions provide a platform for teaching best practices and fostering healthy WASH habits (Morgan et al. 2017). According to the joint monitoring report by UNICEF and WHO (2022), globally 71% of schools had basic drinking water services, 14% had limited service (meaning an improved source but no water available), and 15% had no service (either an unimproved source or no source at all). Approximately 546 million children lacked access to basic drinking water services at their schools. Among them, 258 million attended schools that had improved sources but no water available, while 288 million attended schools with no water service. Furthermore, the report revealed that 16% of schools globally had limited, unusable sanitation facilities, and 13% had no sanitation service at all. About 58% of schools provided basic hygiene services, including handwashing facilities with soap. However, 17% of schools had limited service, meaning they had handwashing facilities with water but no soap available, and 25% had no service at all (no facilities or no water available at the school).

Numerous studies have investigated WASH in schools in different countries, highlighting the need for improvements in these facilities. A lack of progress has been identified in developing WASH facilities, particularly in response to a pandemic like COVID-19 (Cronk et al. 2021; Poague et al. 2023). The most common issues affecting student attendance and health include inadequate access to water, poor sanitation, and poor hygiene practices (Ana et al. 2008; Bah et al. 2022; Meydanlıoğlu & Köse 2022; Vijayalakshmi et al. 2023). These studies emphasize the critical need for targeted interventions to improve WASH facilities in schools.

In Bangladesh, over 45 million children attend school, where they spend a significant part of their day (Save the Children 2024). Therefore, it is crucial to ensure adequate safe drinking WASH in school for their well-being (Anthonj et al. 2021). Currently, more than 3 million schoolchildren in Bangladesh lack access to safe drinking water, clean toilets, and handwashing facilities (UNICEF 2022). The joint monitoring report by UNICEF and WHO (2022) indicated that about 7% of schools lack basic WASH facilities, with 20% lacking safe drinking water supply. This adversely affects approximately 8.5 million children in Bangladesh. The report also mentioned that approximately 43% of schools in the country do not have gender-segregated toilets, and about 44% lack handwashing facilities with soap and water, impacting around 19 million schoolchildren.

Bangladesh made significant progress in WASH services, including schools, through various government initiatives with support from donors and international agencies. However, the delivery of safe WASH facilities in schools, particularly safe drinking water, remains unsatisfactory and an issue that might hinder universal access to safe water by 2030 (Ngcongo & Tekere 2023; WHO 2023). Several studies in Bangladesh have investigated the public health impacts of water quality, sanitation, and hygiene issues in schools (Hoque et al. 2015; Islam et al. 2015; Alam & Mukarrom 2022; Hossain et al. 2022). A survey of 49 primary schools in Gaibandha Sadar revealed that most students relied on shallow tube wells for drinking water and lacked proper sanitation facilities (Islam et al. 2015). Hoque et al. (2015) evaluated the water quality and sanitary conditions of tube wells in 15 educational institutions in Mirzapur Municipality of Tangail district and found that the water quality parameters met the Bangladesh Drinking Water Quality Standard (ECR 2023), except for Fe. Hossain et al. (2022) discovered that total coliform counts in drinking water in schools of coastal areas in Bangladesh exceeded the national drinking water standard. Alam & Mukarrom (2022) analyzed 50 drinking water samples from schools in Chattogram City and found that 52% of the water samples were contaminated with coliform, 28% with fecal coliform, and 46% exceeded the acceptable limit for total viable counts (>500 CFU/mL). The study also reported adequate and unclean toilets, indicating limited sanitation facilities.

There are significant knowledge gaps regarding the quality of WASH services in schools and institutions in Bangladesh. This is due to a lack of capacity and sustainable management of WASH facilities. Additionally, there is a lack of comprehensive studies that simultaneously evaluate drinking water quality, sanitation, and hygiene. To address this issue, this study was conducted to comprehensively evaluate the quality of WASH in Tongi, located in the northern part of the capital, Dhaka, Bangladesh. Tongi is a mixed area that includes industrial hubs, urban, and rural sectors. Various industries such as metal, garments, jute, textiles, pharmaceuticals, and food manufacturing are located in the industrial hubs (Rahman 2012). A significant amount of industrial and municipal wastewater is being generated in this area, much of which is being disposed of into rivers and low-lands untreated. This significantly impacts the groundwater quality (Mukherjee et al. 2006) as well as the primary source of water in the area (Karim et al. 2023). This region's industrial activities and waste disposal practices highlight the critical need for comprehensive WASH assessments.

The main goal of this study was to assess the situation of WASH services, including the quality of potable water, hygiene, sanitation, and solid waste management, in 43 schools in the Tongi area of Bangladesh, find out the gaps in WASH services in schools and identify the strategies to be adopted in meeting SDG 6. The objectives of the study were (a) to review the availability and functionality of WASH infrastructures and (b) to evaluate the quality of drinking water in most of the designated educational institutions situated in Tongi. The study findings will contribute to making informed decisions, developing strategies for addressing water quality and other WASH issues, and helping to improve hygiene, sanitation, and solid waste management status in mixed industrial, urban, and rural areas worldwide to ensure the health and safety of school communities.

Throughout the survey, the heads of the respective educational institutions were the principal respondents. The field survey and questionnaires were administered by the study team in person using paper-based questionnaires, to ensure accurate and consistent responses. The study team was oriented to minimize interrater variability and ensure uniform data collection across all 43 schools. Each respondent received a 5-min briefing before participating in the survey to ensure understanding and engagement with the questionnaire. Survey responses were entered and analyzed in Microsoft Excel using descriptive statistics, including percentages, to assess the status of amenities such as the source of water, condition of sanitation facilities, availability of handwashing stations, prevalent sanitation practices, and solid waste management efficacy. A scale ranging from poor to excellent was used for this assessment. On-site observations were conducted to validate and supplement the survey results, identify any inconsistencies, and provide further insight into the quality and functionality of the facility. The observations were recorded on tabulated sheets, as shown in Table S2, Supplementary Material. In addition to verifying the hygiene and accessibility of the sanitation facilities, the observations provided specific information about the presence or absence of such amenities. A tabulated matrix, incorporating the same rating scale (poor to excellent) utilized in the survey, was employed for the on-site observation conducted by the authors. Additionally, the authors noted pertinent observations as comments within the matrix.

A total of 43 water samples were collected from the drinking water sources of various educational institutions between January and March 2023. These samples were collected during the same visits as the on-site observations. Samples were collected into 500-mL pre-cleaned, sterilized Polyethylene Terephthalate (PET) bottles following Standard Sampling Procedures (APHA 1998). Before sampling, bottles were washed properly with the source water and then filled completely with source water to ensure no air was entrapped into the sampling bottles. After capping, the sample ID, location, institution name, and sampling date were noted on each sample bottle and preserved in a sampling box at 4 °C temperature. Water samples were transported on the same day to the Environmental Laboratory of the Islamic University of Technology for subsequent physicochemical and bacterial analysis.

The physicochemical attributes encompassing pH, color, turbidity, dissolved oxygen (DO), total dissolved solids, total solids (TSs), electrical conductivity (EC), iron (Fe), manganese (Mn), and arsenic (As) were ascertained for each water sample. These parameters were chosen due to their relevance in assessing drinking water quality and potential health impacts, as highlighted in previous studies (Hoque et al. 2015). Water pH, EC, and DO were measured using a calibrated portable multi-parameter meter (HACH HQ40D). Turbidity was determined using a portable turbidimeter (HACH 2100Q), while color was measured using a spectrophotometer (HACH DR2800). TS and Total Dissolved Solids (TDSs) were determined by filtering 100 mL of water using the standard methods as outlined in APHA (1998). Iron (Fe) was determined using the FerroVer 4 sachet, and manganese (Mn) was determined using the periodate-oxidation method. Both analyses were performed using the HACH DR2800 spectrophotometer (Karim et al. 2023). Arsenic (As) content was measured using the HACH Arsenic Test Kit (Reddy et al. 2020). All parameters were measured twice, and the average of these paired measurements was reported as the water quality parameter for each respective sample. Quality control included the use of calibrated instruments, cross-checks with control samples and blank samples.

The enumeration of Escherichia coli (E. coli) populations was conducted for each water sample utilizing the membrane filtration method in accordance with the American Public Health Association (APHA 1998). Initially, a volume of 100 mL of the water samples was subjected to filtration through membrane filter paper with a pore size of 0.22 μm (Millipore Corp., Bedford, MA, USA). Subsequently, the filtrated membranes were placed onto two distinct culture media, specifically modified tryptone bile agar with 4-methylumbelliferyl-ß-D-glucuronide for E. coli within glass Petri dishes. These Petri dishes were then incubated for 24 h at a temperature of 37 °C, after which the populations of E. coli were enumerated. The quantified counts of E. coli are expressed as colony-forming units (CFU) per 100 mL of the respective water samples.

The study utilized the Integrated Water Quality Index (IWQI) proposed by Mukate et al. (2019) to assess the overall water quality using measured physicochemical parameters. The IWQI was calculated through a series of steps, including establishing the relevant parameters, determining the desired limits (DLs) and permissible limits (PLs) based on Bangladesh Drinking Water Standards (ECR 2023) outlined in Table 1, calculating sub-indices for each parameter, and combining these sub-indices to yield the IWQI as a cumulative result.

Initially, a set of eight physicochemical parameters, namely pH, DO, TDS, color, turbidity, Fe, As, and Mn, were selected. Subsequently, DLs and PLs were established for each parameter, with the range being defined as the difference between PL and DL. The modified permissible limit (MPL) was determined by subtracting 15% of the value of the range from the PL (Mukate et al. 2019). The derived MPL, along with the range, DL, and PL, are presented in Table 1.

If the concentration of any parameter either falls below the DL or exceeds the PL, then the sample is indicative of compromised water quality. Thus, if the monitored value of the parameter of the water sample (⁠⁠) was less than the DL, then the sub-index (SI2) was determined by dividing the difference between DL and with DL (⁠⁠). Similarly, when was greater than PL, sub-index (SI3) was expressed as the difference between MPL and over PL (⁠⁠). Conversely, when was within the range of DL and PL, the sub-index (SI1) was assigned a value of 0, representing excellent water quality. Finally, the determination of the IWQI for a specific sample was achieved through the summation of all the sub-indices corresponding to each parameter.

Each parameter of the water samples was analyzed using descriptive statistics, including maximum, minimum, and mean values. The percentage of samples that exceeded both Bangladesh Drinking Water Standards and World Health Organization Guideline Values (WHOGVs) was determined. A one-way Analysis of Variance (ANOVA) test with a 5% significance level was conducted to assess whether there were any significant differences in water quality between the four study zones. The distribution of survey responses across various categories was also analyzed to assess WASH services. All statistical analysis was performed in Microsoft Excel.

Correlation analysis was conducted using Pearson correlation coefficients, as the parameters being evaluated (e.g., pH, EC, Mn, Fe) are continuous and normally distributed. Pearson correlation was chosen because it measures the strength and direction of linear relationships between these continuous variables. The correlation results are provided in Table S6, Supplementary Material, showing how individual water quality parameters, such as Mn (r = 0.89), Fe (r = 0.12), and EC (r = −0.07), correlate with the IWQI.

The physicochemical and bacteriological parameters of the water, as measured in this study, were compared with Bangladesh Drinking Water Quality Standards (ECR 2023) and WHOGVs (WHO 2022). Descriptive statistics for these parameters are presented in Table 2 . The pH, TS, and As levels in all water samples were within the WHO-recommended levels and Bangladesh Drinking Water Quality Standards. However, several physicochemical parameters exceeded the PLs. Mn concentrations higher than the WHO and Environmental Conservation Rules (ECR) 2023 threshold of 0.1 mg/L were detected in about 89.72% of the samples and 35% of the water samples exhibited iron (Fe) concentrations that exceeded the WHOGV of 0.3 mg/L. Moreover, 41.86% of the water samples exhibited EC values exceeding the WHOGV of 400 μS/cm. A higher EC in drinking water indicates the presence of a higher concentration of dissolved minerals and ions in water. However, the correlation coefficient (−0.13 and −0.14 for Fe and Mn, respectively) implies that elevated concentrations of Fe and Mn do not substantially influence the EC values.

In terms of bacteriological parameters, both ECR (2023) and WHO (2022) state that E. coli should be completely absent in drinking water. The study findings presented in Table 3 demonstrate that drinking water sources in all the schools were contaminated by E. coli and its levels exceeded the standards in 100% water samples, thus posing a significant health risk to the students. The mean value of the E. coli level of 43.95 CFU/100 mL was found in the drinking water samples in school, indicating severe contamination issues that pose immediate health risks to the students and staff of schools. WHO (2022) risk categories based on E. coli counts were used for water sources in schools, as illustrated in Table 3. Alarmingly, 84% of the institutions were in the intermediate-to-high-risk category, which highlighted the widespread nature of water contamination. The questionnaire survey, field investigation, and water quality results revealed a correlation between the hygiene condition of water storage and E. coli contamination. It was observed that all the institutions falling into the intermediate-to-high-risk categories had inadequately maintained and unclean water storage facilities (Tables S3–S5, Supplementary Material).

In the vicinity of the industrial area, 33.33% of the samples are classified as low risk, while 66.67% are categorized as intermediate risk. In the residential area, 26.32% of the samples are deemed low-risk, 68.42% fall into the intermediate-risk category, and 5.26% are classified as high-risk. Thus, the majority (73.68%) of the water samples from residential areas pose an intermediate or high risk, indicating a significant health hazard due to E. coli contamination in the drinking water. In the rural area, 13.33% of the samples are classified as low risk, 80.0% fall into the intermediate-risk category, and 6.67% are identified as high risk. Similar to the residential area, the majority of the water samples (86.67%) fall into the intermediate or high-risk categories in terms of E. coli presence. Overall, the analysis results indicate that drinking water supplies in schools in rural and residential areas are severely contaminated with high levels of E. coli, thus causing severe illness among the schoolchildren of these institutes by waterborne diseases. This necessitates immediate attention to protect the health of schoolchildren in these areas.

The correlation analysis (Table S6, Supplementary Material) shows a strong positive correlation (r = 0.89) between Mn and IWQI in the water samples, indicating Mn contributes the highest IWQI in water samples. However, other water quality parameters exhibit weaker correlations, suggesting less association with IWQI values in the samples. Schools equipped with filtration systems for drinking water demonstrate excellent or good water quality. Schools equipped with filtration systems for drinking water demonstrate excellent or good water quality (sample no. 15, 307 19, 27, 38, and 41). Although, schools (samples 2 and 4) have facilities for water filtration for drinking water, water samples from these two schools exhibit the highest IWQI, possibly due to the ineffectiveness of the filtration systems to remove Mn. Implementing cost-effective water treatment technologies like membrane filters, activated carbon filters, or reverse osmosis units can reduce levels of contaminants such as Mn, Fe, and microorganisms. Regular maintenance and monitoring of these systems are essential for effectiveness.

The survey results showed that every educational institution relies on deep tube wells as the main water supply source. Submersible pumps are commonly used for water extraction, which are stored in the overhead reservoirs and distributed through an internal distribution system using mostly Polyvinyl Chloride (PVC) pipes in these institutions. Students use tap water as their drinking source throughout the school day because it is readily available. Additionally, each of the 43 educational institutions affirmed the provision of water accessibility for individuals with limited mobility or vision. As a result, all surveyed institutions meet the criteria for an ‘Improved’ water source and ‘availability’ of water, thereby fulfilling the standards for providing ‘Basic service’ of drinking water as outlined in the Joint Monitoring Program (JMP) service ladders for monitoring WASH in schools within the SDG framework (JMP 2024).

However, only 40% of the schools have their WASH block within 10 m of the deep tube well (Desk 2022). This close proximity poses a potential risk of water contamination by fecal and pathogenic microorganisms. Furthermore, it was found that only 19% of the schools are equipped with reverse osmosis filtration systems for drinking water, indicating a relatively low prevalence of filtration systems in educational institutions for treating drinking water for schoolchildren. Notably, the water supply of all 43 institutes exhibited high E. coli and IWQI indicated that 34.88% of the samples are unsuitable for drinking. This indicates the need for enhancement in water quality to align with the criteria delineated by the SDGs for achieving an ‘Advance level’ of drinking water service.

The survey and field investigation results revealed that all the institutions had ‘improved’ sanitation facilities. The conditions of the toilets in educational institutions were evaluated based on the criteria presented in Table 4. Though most institutions have toilets in at least moderate conditions (83.72%), improvements are needed in institutions with fair and poor conditions to ensure a safe, hygienic environment for students and staff. Consequently, among 43 institutions, 36 meet the criteria for having ‘usable’ sanitation facilities.

The survey results revealed that each institution has separate toilet facilities for male and female students. However, more than 20% of surveyed institutions do not have separate facilities for male and female teachers. This discrepancy in provision raises concerns regarding equitable access to adequate sanitation facilities for the teaching staff, indicating a need for improvement in ensuring gender-specific facilities for teachers in educational institutions. Moreover, only 17% of the schools have separate toilet facilities for physically disabled students. Regarding the location of the student toilets, 23 institutions had toilets within school buildings, while 20 institutions had toilets outside the school building but on school premises. This finding highlights a significant gap in accessibility and inclusivity, as students with physical disabilities may face challenges in accessing appropriate toilet facilities that cater to their specific needs.

Regular desludging is imperative for the proper function of the septic tank and a recommended interval of once every 2–3 years is needed (Yuwono et al. 2021). The majority of institutions, about 56%, reported annual desludging, indicating a reasonably consistent practice for desludging. Approximately 42% of the institutions reported desludging every 2 years, suggesting a less frequent but still regular approach. It is to be noted that 2% of the institutions conducted desludging based on the overflow condition of the conduit. Therefore, these institutions are categorized as having ‘limited’ sanitation services according to the JMP service ladders for monitoring WASH in schools within the SDGs framework.

All institutions surveyed exhibited handwashing facilities equipped with water and soap, available on-site at the time of assessment and accessible to those with limited mobility or vision.

Regarding the solid waste management of these institutions, it was found that every institution used plastic bins for the collection of daily solid waste. Approximately 50% of the institutions collect their solid waste (garbage and rubbish) either once every 2 days or once a week. However, concerning findings have emerged regarding the disposal methods employed. Only 12% reported discarding waste in or near the waste landfill, while 25% buried their waste on or near the institution premises. Approximately 63% of the institutions burn their waste daily on or near the grounds. Burning the garbage has the potential to lead to long-lasting health complications due to the emission of toxic substances, including nitrogen oxides, sulfur dioxide, volatile organic chemicals, and polycyclic organic matter.

Hence, these institutions are classified as having ‘Basic’ hygiene services in accordance with the JMP service ladders utilized for monitoring WASH in schools under the sustainable development goal framework.

The previous studies in lower-middle-income countries' schools yielded similar findings regarding WASH facilities and water quality. A study in Pakistan (Ahmed et al. 2022) revealed that the coverage of basic WASH facilities in primary schools remains low according to WHO WASH service ladder criteria and all three inclusive domains of WASH facilities (availability, accessibility, and functionality) were inconsistent. Regarding water quality, iron (15%), TDS (33%), and EC (46%) exceeded the WHO PL. Furthermore, drinking water was found to have microbial contamination with total coliform (81%) and fecal coliform (55%). According to WHO (2022), sanitation infrastructure is closely linked to the transmission of diarrheal illnesses such as cholera and dysentery, as well as diseases like typhoid, intestinal worm infections, and polio. Cronk et al. (2021) conducted research in rural schools across 14 low- and middle-income countries. The study revealed that only 63% of the schools had basic water services, with even fewer having basic sanitation (23%) and hygiene (12%) facilities. In Honduras, only 22% of schools met the WHO standards for E. coli levels, while Tanzania exhibited the lowest compliance, with only 16% of schools adhering to the same standards. Similarly, a study conducted in the Bahir Dar City of Northwest Ethiopia by Sitotaw et al. (2023) found similar results regarding water quality. Out of 180 water samples tested, only 16.7% met the total coliform standards, and 73.88% met fecal coliform standards. In Senegal, Sy et al. (2022) observed relatively higher access rates for drinking water (73%) and sanitation (72%) among households, schools, health centers, and infrastructure points. Morgan et al. (2017) studied the access, continuity, quality, quantity, and reliability of WASH services in 2270 schools across 6 Sub-Saharan African countries. The study found inadequate access to basic WASH services in these schools, which adversely affected the health, education, and gender disparities of the students.

This study found that E. coli was present in all drinking water samples in schools. Additionally, 55.81% of the water samples were found poor and unsuitable for drinking purposes. The drinking water source in the study schools is comparatively inferior and unsuitable in comparison with similar study findings globally (Cronk et al. 2021; Ahmed et al. 2022; Sy et al. 2022; Sitotaw et al. 2023) and locally (Islam et al. 2015; Alam & Mukarrom 2022; Hossain et al. 2022). Factors contributing to high levels of E. coli in drinking water included improper cleanliness of overhead storage tanks, absence of disinfection facilities, the proximity of tube wells to WASH blocks (<10 m) and unhygienic practices. Although some schools used filtration systems, these systems were found not clean and well maintained as per guidelines, rendering them ineffective in meeting microbial drinking water standards. Moreover, elevated levels of Mn and Fe in the water could potentially pose health risks for elderly individuals, such as Parkinson's disease, ageing, heart disease, and Alzheimer's disease, as well as impact brain development in young children (Guilarte 2010; Mirlohi et al. 2011). All surveyed schools had access to available water supply, meeting the basic service criteria outlined in the SDGs framework. Access to safe drinking WASH is crucial for child development, as schools play a vital role in promoting healthy hygiene habits among children. According to United Nations International Children's Emergency Fund/World Health Organization (UNICEF/WHO), a significant number of schools in Bangladesh are ill-equipped to provide healthy and inclusive learning environments for all children.

Further analysis revealed significant relationships between water quality, sanitation conditions, and school characteristics. Schools with better infrastructure, including water sources and toilets, had improved water quality and sanitation. Additionally, the socioeconomic status of the schools also influenced the quality of water and sanitation, with schools in more affluent areas having better access. Multivariate analysis identified budget allocation, government support, and community engagement as key factors influencing the success of water and sanitation improvements.

The study findings revealed that WASH facilities coverage and services in the study schools are comparatively better than the national average, as reported by UNICEF and WHO (2022). However, the presence of high manganese levels in several samples, which suggests potential industrial contamination, was unexpected based on previous studies in similar contexts (Karim et al. 2023). This discrepancy emphasizes the need for further investigation into the specific sources of contamination in the Tongi area. Although the schools have the basic drinking water services, the quality of the drinking water is a significant concern. There are no facilities or committees at the school level to monitor the WASH infrastructures or water quality. Sultana et al. (2023) demonstrated the role of the school-based hygiene committee (student, teacher, and school management committee) in institutionalizing school-based hygiene interventions and ensuring the sustainability of WASH facilities in schools. The outcome of this study indicates that school-based hygiene committees can successfully maintain WASH interventions in schools if they are properly trained, motivated, and supported. Schools lack facilities for water quality monitoring and disinfection, especially chlorination, as well as funds for consumable recurrent costs for hygiene facilities. In Bangladesh, the National Strategy for Water Supply and Sanitation provided a comprehensive framework for the WASH sector to address new and emerging challenges to align with the SDGs after the Millennium Development Goals (MDGs) (LGD 2021). This strategy provided directions for increasing coverage and improving the quality of WASH interventions, such as expanding safe and sustainable drinking water and sanitation facilities. However, the national strategy does not include water quality monitoring and assessment in schools, although it acknowledges the importance of WASH services and health outcomes and schools lack curriculum or training on hygiene behavior. Therefore, a strategic framework needs to be developed and implemented at the national level to establish hygiene committees, mechanisms for assessing water quality and WASH facilities, financial support mechanisms for recurrent costs of WASH facilities, community involvement, and the incorporation of WASH and hygiene education in schools. These will ensure the proper functionality of WASH facilities in schools. Routine monitoring of drinking water quality in the school, training and awareness of the school community, and collaboration between government bodies and local organizations to support schools in providing and maintaining WASH standards should be included in the framework as part of action plans. Point-of-use water treatment technologies, such as mineral pot filters, chlorination, and membrane filtration with ultraviolet (UV) disinfectants, can effectively provide protection against microbial contamination and should be promoted in educational institutions (Ahmed et al. 2022) for safe drinking water supply.

To ensure sustainable improvements in water and sanitation in schools, active participation from all stakeholders is crucial. This includes involvement from the school community and parents in the planning, implementation, and maintenance of water and sanitation facilities. Implementing effective WASH interventions requires significant resources. The costs of installing and maintaining water filtration systems, regular water quality testing, WASH campaigns, cleaning the WASH facilities and others need to be considered. Thus, continued support from local governments, both in terms of funding, technical guidance, and training programs, is necessary for the successful implementation and operation of these systems to ensure long-term sustainability.

The limitations of this study include limited coverage of schools in a specific region, which may affect the generalizability of the findings. Moreover, the assessment of sanitation conditions relied on visual observations and interviews, without comprehensive laboratory testing. This limitation may impact the accuracy of the evaluation of sanitation quality. Therefore, further studies with broader coverage and more diverse data collection methods are recommended to obtain a more representative picture of the WASH situation in schools.

The provision of safe drinking water and adequate sanitation facilities is crucial for creating a healthy learning environment. However, the lack of these resources hinders the efficacy of promoting good hygiene behaviors in schools. Although all the surveyed schools have adequate water supply and basic sanitation and hygiene practices, the schools lack a supply of safe drinking water. This investigation revealed that drinking water in schools was contaminated with E. coli. Additionally, the IWQI value suggested that some of the physicochemical parameters of the water in most of these institutions were also unsuitable for drinking, primarily due to the presence of a high Mn level. The study found elevated EC values in nearly half of the samples, but no correlation was found with analyzed ions, such as Fe and Mn. This suggests the need for further investigation into other ions, especially heavy metals in drinking water. Most of the water sources in the institutions are located in close proximity to the toilets, which may cause major microbial contamination of the water sources. Furthermore, moderately maintained toilet facilities were in the majority of institutes, with handwashing facilities. This study and others (Cronk et al. 2021; Bah et al. 2022; Ngcongo & Tekere 2023) found that schools do not have provisions for monitoring the quality of drinking water, which is essential for ensuring the safety of drinking water. Water of poor quality may contribute to negative health effects and affect safe WASH facilities.

This study strongly recommends the development of a strategic framework for ensuring safe WASH in schools. Key recommendations include establishing functional school-based WASH committees, implementing routine water quality monitoring programs, adopting cost-effective point-of-use water treatment technologies, and collaboration and support from the local government for providing and maintaining the WASH standards. These measures are essential for safeguarding the drinking water quality for school children and ensuring compliance with SDG 6.1 and 6.2 targets.

Moreover, more than half of the institutions burn their solid waste, which has adverse effects on the environment. To comprehensively understand and improve WASH conditions, the schools' authorities should develop and consistently maintain an observation checklist. The findings of this study have important implications for WASH policies and practices in schools. The research findings can help understand the gaps in WASH practices in schools, which lead the policymakers at the regional and national levels to prioritize the improvements necessary to access clean water and sanitation for attaining SDG 6. The relevant stakeholders and decision makers, such as government bodies and local organizations, shall develop a strategic framework for safe WASH facilities, including regular analysis of water quality. This study also contributes to understanding the challenges and potential improvements needed to ensure a safe and hygienic learning environment for students in schools.

The authors declare that there is no financial support received.

Md. R. K. conceptualized, designed and supervised the whole process, revised the manuscript. S. S. and A. F. performed the checklist development, field survey, developed the water sampling and analysis. Md. R., R. H., and Md. T. I. rendered support in data analysis, interpreted the work, and drafted the manuscript. Md. M. H. K. and Md. H. R. B. K. reviewed and edited the manuscript.

All relevant data are included in the paper or its Supplementary Information.

The authors declare there is no conflict.