Next Article in Journal
Deep Learning-Based Retrieval of Chlorophyll-a in Lakes Using Sentinel-1 and Sentinel-2 Satellite Imagery
Previous Article in Journal
Dark Fermentation of Sizing Process Waste: A Sustainable Solution for Hydrogen Production and Industrial Waste Management
Previous Article in Special Issue
Two-Dimensional Analysis of Air–Water Interaction in Actual Water Pipe-Filling Processes
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Water
Volume 17
Issue 11
10.3390/w17111717
water-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Survey of School Direct-Drinking Water Access for Children and Youth in Shanghai, China

by
Yuan-Shen Zhu
1,2,
Bing-Qing Hu
1,2,
Rong Zheng
1,2,
Ya-Juan Wang
1,2,
Wei-Wei Zheng
3,4 and
Min-Juan Yang
1,2,*
1
Shanghai Pudong New Area Center for Disease Control and Prevention (Shanghai Pudong New Area Health Supervision Institute), Shanghai 200136, China
2
Fudan University Pudong Institute of Preventive Medicine, Shanghai 200136, China
3
School of Public Health, Fudan University, Shanghai 200032, China
4
Key Lab of Health Technology Assessment, National Health Commission of the People’s Republic of China, Fudan University, Shanghai 200032, China
*
Author to whom correspondence should be addressed.
Water 2025, 17(11), 1717; https://doi.org/10.3390/w17111717
Submission received: 18 April 2025 / Revised: 29 May 2025 / Accepted: 31 May 2025 / Published: 5 June 2025
(This article belongs to the Special Issue Design and Management of Water Distribution Systems)
Browse Figures
Versions Notes

Abstract

Background: Over the past decade, Shanghai primary and middle schools have installed and updated direct-drinking water facilities in compliance with local policies, but few studies have assessed the schools providing direct-drinking water access. Methods: A cross-sectional study was conducted with 167 public primary, middle, and high schools across Pudong New Area, Shanghai during Autumn 2024. The type, location, and working condition of all direct-drinking water facilities throughout each school were documented by trained research staff using a direct observation protocol. Information on school direct-drinking water quality was obtained from the routine monitoring program. Data were analyzed for comprehensive assessment of direct-drinking water facilities in the schools. Results: On average, each school had one faucet of direct-water facility per 41 students; 70% of the schools met the requirement for minimum direct-drinking water access, and >90% placed facilities in high-traffic areas. In addition, 83% of the schools selected water facilities with nanofiltration and a hot water system, and most only provided hot water (above 50 degrees Celsius). For school direct-drinking water quality, the concentrations of hardness, chemical oxygen demand (COD), and total dissolved solids (TDS), as well as pH values, were improved significantly, but the total bacteria count was prone to not meeting the requirement for standards in middle and high schools, which could be caused by insufficiency of chlorination in pumping stations or neglecting to clean facilities promptly. Conclusions: Wide usage of school direct-drinking water facilities could help most public schools to meet local policies for minimum student drinking water access in Shanghai, but microbial contamination was the potential threat. Water temperature is the key factor affecting students’ drinking water, providing an optional water temperature for students’ preferences and concerns. National sanitary standards of direct-drinking water quality and relevant additional regulations should be established and implemented in China.

1. Introduction

Adequate access to safe, clean water is essential for health, in particular, proper circulatory and metabolic function for children and adolescents [1,2]. Most Shanghai children and youth spend much of their time—on average 9.5 h per day for about 200 days per year—in public school settings [3]. The inadequate hydration status of students is an issue in China [4,5]. It is crucial, therefore, that schools provide students with access to safe, free, clean drinking water during the day. Considering the demand for high-quality drinking water, schools have substituted boiled tap water with direct-drinking water in Shanghai, China.
Direct-drinking water originated from the conception of dedicated drinking water systems (DDW) with tertiary treatment of water in which tap water, as source water, is processed by deep purification treatments (i.e., membrane filtration) [6,7]. Tap water, also called drinking water in standards, is considered to be potable, but it is possible that certain contaminants could be introduced by long-distance water delivery and water storage from the water system to the tap [8,9,10]. Direct-drinking water facilities are defined as bottle filling stations with advanced water treatment, which have gained general popularity in China due to cost considerations (Figure 1) [7]. Unfortunately, these facilities still have a risk of water contamination due to maloperation. The 2005–2017 direct-drinking water sanitation analysis reported that 80.02% of direct-drinking water met standards for drinking water quality (GB 5749) on average, lower than 85.15% in contemporaneous tap water, and the main factor in health risk was microbial contaminant [11]. Thus far, on the other hand, no national water quality standard for direct-drinking water has been implemented in China.
Shanghai agencies set standards for the construction and maintenance of direct-drinking water facilities in primary, middle, and high schools in 2013 and additional regulations for the hygienic management requirements for school direct-drinking water in 2022 [12,13]. Meanwhile, the Shanghai Municipal Government initiated the direct-drinking water treatment project in both elementary and middle schools, completing the installation of direct-drinking water facilities in a total of 1200 schools between 2013 and 2015 [14]. Usage of these facilities could help improve students’ water intake and habits to some extent [15]. On the other hand, the inspecting agency of the Shanghai municipal health commission tested 549 samples of direct-drinking water from 183 elementary and middle schools in Shanghai for colony-forming units (CFU), residual chlorine, chemical oxygen demand (COD), and turbidity and found that factors including schools in rural areas, providing warm water, with a non-pipe faucet type and using ultrafiltration/microfiltration could increase the risk of microbial contaminants [16]. Despite these policies, few studies have assessed the adequacy of direct-drinking water access in schools and whether there was a need for public health action to improve the water intake of children and youth.
Our aim was to assess whether the school direct-drinking water facilities meet the local standard requirement for water accessibility and safety using a direct observation protocol in a sample of public primary, middle, and high schools throughout Pudong New Area, Shanghai. Meanwhile, we collected information on water quality in inlets and outlets of school direct-drinking water facilities from the dataset of 2024 Pudong drinking water quality regulatory oversight. The Pudong New Area, lying in the east of Shanghai city, has a total area of 1210 square kilometers and a permanent resident population of 5.77 million, which accounts for approximately 20 percent of the city’s total [17]. We also discussed the challenge of further improving the appeal of student drinking water.

2. Materials and Methods

2.1. Study Design

We conducted a cross-sectional study in public schools across all 47 sub-districts in Pudong New Area, Shanghai between September and October 2024. The sub-districts were determined by community health service areas in this study. In total, 188 schools were invited to participate, with two primary, one middle, and one high school randomly chosen from each sub-district. Of these, 167 schools (89%) agreed to participate and finally formed the sample in the present analysis. The distribution of the participating schools on the map is shown in Figure 2. In this study, school drinking water contained tap water and direct-drinking water, and they shared the same standards for drinking water quality (GB 5749) [10]. Generally speaking, school direct-drinking water was defined as drinking water supplied from bottle-filling stations with point-of-use advanced water treatment or barreled pure water dispensers in school. Tap water in schools may meet drinking requirements but is actually used for washing hands. Each participating school was visited by trained research staff on one day to complete a direct observation of direct-drinking water availability at the school.

2.2. Data Collection

For the on-site observations of water access, a standardized protocol was used by trained research staff when they visited each participating school [18]. The survey covered school-level demographic information, aesthetic properties of direct-drinking water, characteristics and features of direct-drinking water facilities, location and placement of water supplies, upkeep and maintenance of water facilities, and education and promotion to encourage drinking water intake [19]. Research staff walked through each direct-drinking water access point and checked the relevant standing book to complete the survey. More details are shown in Text S2.
In order to identify the presence of school drinking water safety, the information on school drinking water quality was gathered from the data collection of the China national drinking water quality regulatory oversight. A total of 53 records from the monitoring points of 23 schools’ tap water and 30 schools’ direct-drinking water were involved in this study. For water treatment in schools, the inlets of such facilities shared the same building plumbing with the tap. Hence, sampling was conducted annually from one tap and/or two outlets of dispensers of each monitoring point in Pudong New Area. Sample collection and relevant analytical methods in the water quality regulatory oversight are described in detail in Text S1. The tap water system in Shanghai, including water sources, traditional and tertiary water treatments, and water delivery processes, was described in our previous study [20].

2.3. Measures

School water treatment facilities were considered as the key factor at play in school direct-drinking water safety and access. The water treatment process was captured by these response options (multiple responses): activated carbon adsorption, nanofiltration, reverse osmosis, ultrafiltration/ microfiltration (UF/MF), boiling (or combined with cooling by heat exchange), and purchasing barreled/bottled drinking water. The frequency of water quality testing and dispenser cleaning at the school was determined by these response options: more than or monthly, monthly, less than monthly but at least twice a year, and seldomly tested or not. Research staff documented the water facilities’ locations, brands, faucet amounts, water temperature settings, and additional functions (e.g., SET-TEMP, faucet or outlet auto clean, online feedback). Research staff were also trained to take detailed qualitative notes about their perceptions of the water facility’s appearance (e.g., whether the inlet and outlet was rusty, had dirt or grime on the faucet or trash in the basin, used non-slip or waterproof materials on the floor, had a display of prompts, etc.). Total enrollment, management and support information, and water promotion activities were obtained from the standing book of each school.
In this study, microbial, chemical, and acceptability aspects were considered for school tap/direct-drinking water quality. For microbial aspects, E. coli (or thermotolerant coliforms) and total bacteria count were used as indicator organisms. Inorganic contaminants were the key chemical health hazards related to school drinking water, such as arsenic, chromium, lead, cadmium, and mercury. Some naturally occurring chemicals, such as hardness (CaCO3), aluminum, iron, manganese, copper, zinc, pH, chemical oxygen demand (COD), and total dissolved solids (TDS), were also described. Acceptability aspects included sensory perceptions like odor, color, turbidity, and temperature. Total chlorine, as the indicator of disinfectants, was only tested in school tap water.

2.4. Statistical Analysis

We calculated the total number of drinking water dispensers and faucets for each school and the average number of students served by each faucet, as well as the proportion of those schools that had a potential health risk in its drinking water. We also calculated the qualified rate of school water quality by comparing levels of various indicators with the corresponding guideline values from the local and national standards for drinking water quality [21,22]. What is more, these local and national standards were stricter than WHO guideline values [23].
Nanofiltration (NF) and reverse osmosis (RO) were the core processes in direct-drinking water treatment, with activated carbon adsorption, ultrafiltration/microfiltration (UF/MF), and/or boiling as additional processes. There was no water treatment process in some schools, which used barreled water dispensers with a heating function. Hence, four modes of school direct-drinking water treatment were captured: first, “nanofiltration” was used for schools that only have water facilities using NF technology; second, “reverse osmosis” was used for schools that only have water facilities using RO technology; third, “barreled/bottled drinking water” was for schools only using barreled/bottled water dispensers; and the rest were classified as a mixed mode. Water temperature settings were dichotomized into either “within the range of 20 °C to 40 °C” or not, based on the requirement of the Shanghai local policy for school drinking water [13].
Relationships between variables of school direct-drinking water access and types and locations of school were examined using Pearson chi-square tests. The Mann–Whitney U test was used to indicate the variability of the qualified rate or the concentration of various indicators in school tap water and school direct-drinking water. A two-sided p-value < 0.05 was considered statistically significant. All statistical analyses were conducted by using R 4.1.1 (R Core Team 2021, Vienna, Austria).

3. Results

3.1. Characteristics of the Study’s Schools

Among the 167 schools observed, more than half were primary schools (88), and the others were middle and high schools (79). The average numbers of students and school staff were 960 (SD: 456) and 78 (SD: 28) in primary schools, 877 (SD: 417) and 82 (SD: 35) in middle schools, and 1053 (SD: 485) and 130 (SD: 48) in high schools. Half of the participating schools (43%) were in the central area of Shanghai with approximately an equal proportion of school types. All sampled schools provided reduced-price lunch and free drinking water, but none provided cups or reusable water bottles next to dispensers. No sampled school was permitted to sell or provide bottled water and sugar-sweetened beverages (SSBs). All schools encouraged students to bring their own water bottles.

3.2. Profiles of Key Components Regarding Direct-Drinking Water Access

Distributions of key components regarding direct-drinking water access among primary, middle, and high schools in central and surrounding areas are shown in Table 1. Only nine brands were involved in this study, due to government procurement in school direct-drinking water facilities generally. There were three main types of direct-drinking water facilities in schools, including water facilities with reverse osmosis and heat function, water facilities with a combination of nanofiltration and a hot water system (Figure 3), and barreled water dispensers with a heating function. The water facilities with nanofiltration and a hot water system were the most popular direct-drinking water facilities among primary, middle, and high schools.
On average, each school had 10.4 (SD: 8.6) and 34.1 (SD: 24.9) direct-drinking water facilities and faucets, with most (>90%) of those facilities being located at high-traffic areas, such as the corridors of school buildings and in proximity to toilets. Each faucet served 41 (SD: 27) students and school staff, and 70% of schools met the requirement for “average less than 45 students served by per faucet”. Most facilities and faucets (>95%) were documented as functioning, but fewer (>70%) were observed to be both clean and functioning at the time of assessment. The water facilities with the combination of nanofiltration and a hot water system were designed to provide “warm water” at 20 to 40 degrees Celsius, but about three-fourths of the water temperatures were above 50 degrees Celsius, which could be out of consideration for preventing bacteria but a bit hot for students. The other two types of direct-drinking water facilities provided both room temperature and hot water (above 90 degrees Celsius). The majority of schools (>75%) had measures for preventing students from slipping, but only half had usage prompts on the facilities, indicating that students were more prone to accidental scalds when using these facilities.
Most schools performed dispenser cleanings and water quality tests at least once a semester. The primary and middle schools paid more attention to the safety management of direct-drinking water. Schools in surrounding areas had a tendency to neglect water quality testing and results announcements. The majority of the schools conducted water education and promotion (assemblies, lessons for students, and display of posters) at least once a year concerning the Water World Day, the importance of water consumption for health, water intake recommendations, and so on. The posters and water quality testing results were placed next to direct-drinking water facilities and in other high-traffic areas at the schools.

3.3. Profiles of Key Components Regarding Direct-Drinking Water Quality

The levels of water-quality parameters in school drinking water and tap water (also water from outlets and inlets of the school direct-drinking water facilities, respectively) are shown in Table 2. About a third of the total bacteria counts in the school direct-drinking water and tap water were ≥2 CFU/100mL, and of these, six were more than 50 CFU/100mL (DB/T 1091-2025) and four were more than 100 CFU/100mL (GB 5749-2022) and did not meet safety standards. These four samples were all from the schools’ direct-drinking water, with one (130 CFU/100mL) from the primary school and the others (110-320 CFU/100mL) from the middle and high schools. It is noted that the most contaminated sample was from an outdoor facility near the playground. No E. coli was found in any sample. Inorganic contaminants and naturally occurring chemicals in all samples met safety standards. The detection rates of arsenic at the inlets and outlets of the school direct-drinking water facilities were approximately 20%, whereas those of the remaining heavy metal pollutants (i.e., chromium, lead, cadmium, mercury) were not found in any sample. For naturally occurring metals, the detection rates and concentrations of aluminum at the outlets of the school direct-drinking water facilities were lower than those at the inlets, but conversely with those of zinc. In tap water, two samples included detected iron (0.02 and 0.12 mg/L) and another one included manganese (0.01 mg/L). Only one school drinking water sample included detected copper (0.01 mg/L). The concentrations of hardness, chemical oxygen demand, and total dissolved solids, as well as pH values, were also lower at the outlets of the school direct-drinking water facilities. The odor, color, and temperature of school direct-drinking water were consistent with the results of this observation in this study. The total chlorine values in tap water all met the requirements for local standards, but some were lower than the WHO guideline value, indicating that microbial contaminants in direct-drinking water could be caused by an insufficiency of chlorination in pumping stations [21,23].

4. Discussion

The current study used direct observation to comprehensively investigate the school direct-drinking water access for children and youth in Pudong New Area, Shanghai. Direct-drinking water access in this sample of primary, middle, and high schools was relatively sufficient to meet Shanghai drinking water policies. Direct-drinking water facilities were the effective tool to improve drinking water quality in schools, such as reducing inorganic pollutants and mineral contents, but still had the risk of microbial contaminants as well as a need for improving appeal.
Despite the official claims of safety for finished water, there are still potential threats from the waterwork to the tap in Shanghai. Microbes (TBC), chemical oxygen demand (COD), and turbidity levels increase during delivery [24]. Older buildings in the city may have outdated plumbing systems that could further increase the risk of bacterial or chemical contamination in tap water [25]. Therefore, the concern of students and their parents for drinking water safety is a motivation of many schools installing the direct-drinking water facility. Since 2013, almost all public schools have installed and updated direct-drinking water facilities as well as suspended the sale of sugary drinks, in compliance with Shanghai local policies [14]. This study did not investigate the number of students who brought their own drinking water from home, approximately 20% as reported previously by one study conducted in Shanghai [15]. The upgrade from ultrafiltration/microfiltration (UF/MF) to nanofiltration (NF) in schools’ advanced water treatment could contribute to the decrease of COD and turbidity in drinking water, compared with the results of the previous study in Shanghai [16]. Reverse osmosis (RO) and nanofiltration (NF) are widely used as membrane separation technologies worldwide [26,27]. The RO membrane only can allow water molecules and matter smaller than that to pass through due to the pore size of 0.0001μm [26]. The ability of nanofiltration to reject molecular or ionic species is lower than reverse osmosis. Some beneficial nutrients in water, such as magnesium or calcium, could be retained [27]. Boiling, as disinfection, is commonly used with nanofiltration to further remove bacteria and viruses in water, and then, hot water is cooled by a heat exchange system. Water facilities using RO technology also have the heat function generally, but room temperature water and heated water were supplied separately.
The treated water from direct-drinking water facilities could become clean and taste good but still have a risk of bacteria due to slow or stagnant water circulation and the easy formation of biofilm in pipes [8,28,29,30]. Unfortunately, chlorine was not tested in water samples from direct-drinking water facilities in the regular monitoring program. A previous survey in Shanghai reported that the concentrations of total chlorine in direct-drinking water samples were less than 0.05 mg/L (GB 5749) in most schools (86/145), and of these, only 2.3% did not have a risk of microbial contamination [31]. Viable microbes intrinsic to the pipes and tanks of the facilities could thrive in the absence of residual chlorine. Water temperature also plays a key role to suppress the growth of pathogenic bacteria [32]. The WHO reported that bacteria can survive in hot water systems of 20~50 degrees Celsius and that an optimal temperature is 35~46 degrees Celsius [23]. Several studies suggested that drinking water should be heated above 60 degrees Celsius and the hot water system should be kept above 50 degrees Celsius [16,32,33]. Chinese people cultivate the habit of drinking boiled water, and this has become a widespread preference among people of every geographic position. Even with the development of drinking water systems, drinking hot water remains China’s strongest vestige of the past. Though RO technology was superior to NF technology, the water facilities with the combination of nanofiltration and a hot water system had an effective way to prevent microbial contaminants and add minerals for a healthy diet, which could partly explain a greater share of those facilities in the public schools of Shanghai [16,34]. With reference to the reform of water supplied by outdated plumbing systems in residential communities in Shanghai, the current point-of-use (POU) treatment units in school could be replaced by point-of-entry (POE) treatment combined with terminal devices for instant heating [35].
It seemed that public schools in Shanghai had adequate direct-drinking water access based on the number of working water facilities in schools. Schools, on average, provided at least one faucet per 41 students, compared with, for reference, 1.5 water sources per 75 students in the USA [18]. Most water facilities were placed in the corridors of school buildings, passing by or in proximity to a toilet (within 10 m), and students crowding around may not all get a drink of water in time at a 10-min recess. Hot water burns and slipping were the main accidents caused by the facility usage [15]. Additionally, poor direct-drinking water access in school cafeterias and gymnasiums may send a message to students that water is not a beverage of choice during meals and sports [36]. Adding water fountains to current filling stations could be a good way to resolve the problem that students forget to bring a bottle. While functional direct-drinking water facilities are provided adequately, almost a third of these water facilities appeared unclean. Finding dirt or grime on the faucet was a common reason cited by observers for coding a water facility as unclean. Routine monitoring of compliance with school drinking water access policies, including results of water quality testing, records of upkeep and maintenance, protocols for training and technical assistance and so on, may not be enough for assessments of direct-drinking water access in school. In order to improve the existing norms around good quality water in school, it is necessary that stringent national safety standards be implemented, and direct observation should be integrated into routine monitoring protocols.
The main strength of this study was that our investigation used a direct observation protocol by trained research staff rather than self-report to assess direct-drinking water access in school, which covered primary, middle, and high schools with a large sample. Nonetheless, the study is subject to some limitations. First, no private school was included in this survey, which could lead to sample selection bias as private schools were more likely to have more finances to afford facilities with advanced functions like faucet auto cleaning, pipe disinfecting with ultraviolet light, and mineralizing after reverse osmosis. Second, the generalizability of study findings could be limited due to the study only being conducted in Pudong New Area, Shanghai. Third, we did not collect water samples and test water quality when our research staff visited the school, which may not reflect the condition precisely. Additionally, the survey did not include information on drinking habits and satisfaction of direct-drinking access among students in participating schools, so the relationship between school direct-drinking water access and student water consumption was not clear. Future research should focus on examining how observed school direct-drinking water access influences student plain water intake in school and whether it reduces sugar-sweetened beverage consumption after school.

5. Conclusions

The wide usage of direct-drinking water facilities could provide for the basic needs of student access to safe, clean drinking water in Shanghai, but microbial contamination is the potential threat. Further improving the appeal, functionality, placement, and maintenance of direct-drinking water sources may be needed to provide good quality drinking water in school and increase student water intake. Water temperature is the key factor affecting students’ drinking water, providing optional water temperature for students’ preferences and concerns. It is suggested that point-of-use (POU) treatment units could be reformed by point-of-entry (POE) treatment in schools, which could lower the cost of management and the risk of water being contaminated in current direct-drinking water facilities. National sanitary standards of direct-drinking water quality and relevant additional regulations should be established in China as soon as possible.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/w17111717/s1, Text S1: Sample collection and analytical methods; Text S2: Standardized protocols. Reference [37] is cited in the Supplementary Materials.

Author Contributions

Conceptualization, M.-J.Y. and W.-W.Z.; methodology, Y.-S.Z.; software, Y.-S.Z.; validation, B.-Q.H.; investigation, Y.-J.W.; data curation, Y.-S.Z.; formal analysis, Y.-S.Z.; writing—original draft preparation, Y.-S.Z.; writing—review and editing, M.-J.Y. and W.-W.Z.; supervision, R.Z.; project administration, Y.-S.Z. and M.-J.Y.; funding acquisition, M.-J.Y. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Pudong New Area Science and Technology Development-Innovation Fund (No. PKJ2024-Y79).

Data Availability Statement

The data presented in this study are available on request from the corresponding author.

Acknowledgments

The authors would like to thank all the members of Pudong New Area community health service centers for their support.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Hofmeister, M. Emphasise the importance of adequate water intake. Hong Kong Med. J. 2015, 21, 479. [Google Scholar] [CrossRef] [PubMed]
  2. Jequier, E.; Constant, F. Water as an essential nutrient: The physiological basis of hydration. Eur. J. Clin. Nutr. 2010, 64, 115–123. [Google Scholar] [CrossRef] [PubMed]
  3. Fong, J.H.; Feng, Q.; Zhang, W.; Chen, H. Time trend analysis of leisure-time activity participation among young-old adults in China 2002-2018. BMC Public Health 2022, 22, 417. [Google Scholar] [CrossRef]
  4. Wang, X. Current Status Water Intake of Children and Adolescents in Four Cities of China; Chinese Center for Disease Control and Prevention: Beijing, China, 2012.
  5. Wang, Z.; Shi, A.; Chen, Y.; Cheng, W.; Song, J.; Zhu, Z.; Zou, S.; Ma, G. Water intake and its influencing factors of children and adolescents in Shanghai. J. Hyg. Res. 2014, 43, 66–69. [Google Scholar]
  6. Huang, Y.; Wang, J.; Tan, Y.; Wang, L.; Lin, H.; Lan, L.; Xiong, Y.; Huang, W.; Shu, W. Low-mineral direct drinking water in school may retard height growth and increase dental caries in schoolchildren in China. Environ. Int. 2018, 115, 104–109. [Google Scholar] [CrossRef]
  7. Wang, T.; Sun, D.L.; Zhao, T.H.; Zhang, Z.Z. Comparative Analysis of Direct Drinking Water and the Relevant Sanitation Standards in China. J. Sichuan Univ. 2021, 52, 729–734. [Google Scholar] [CrossRef]
  8. Liu, J.; Ren, H.; Ye, X.; Wang, W.; Liu, Y.; Lou, L.; Cheng, D.; He, X.; Zhou, X.; Qiu, S.; et al. Bacterial community radial-spatial distribution in biofilms along pipe wall in chlorinated drinking water distribution system of East China. Appl. Microbiol. Biotechnol. 2017, 101, 749–759. [Google Scholar] [CrossRef]
  9. Liu, C.; Zhu, L.; Pan, M. Seasonal shift of water quality in China Yangtze River and its impacts on membrane fouling development during the drinking water supply by membrane distillation system. Sci. Total Environ. 2022, 810, 152298. [Google Scholar] [CrossRef]
  10. Li, H.; Smith, C.D.; Cohen, A.; Wang, L.; Li, Z.; Zhang, X.; Zhong, G.; Zhang, R. Implementation of water safety plans in China: 2004–2018. Int. J. Hyg. Environ. Health 2020, 223, 106–115. [Google Scholar] [CrossRef]
  11. Wang, T.; Sun, D.; Zhang, Z. Analysis of Sanitary Status and Supervision and Management of Direct Drinking Water in China during 1999-2018. J. Prev. Med. Inf. 2020, 36, 42–47. [Google Scholar]
  12. Shanghai Municipal Commission of Education. Requirements for the Construction and Maintenance of Direct-Drinking Water Facilities in Primary and Middle Schools. Available online: https://edu.sh.gov.cn/xxgk2_zdgz_qtjy_02/20201015/v2-0015-gw_415052013006.html (accessed on 13 April 2025).
  13. DB/T 1361-2022; Shanghai Bureau Market Superintend Management. Hygienic Management Requirements for Drinking Water in Schools. Standards Press of China: Beijing, China, 2022.
  14. Shanghai Municipal Government. The Direct-Drinking Water Treatment Project in Both Elementary and Middle Schools. Available online: https://www.shanghai.gov.cn/nw12344/20200814/0001-12344_35449.html (accessed on 13 April 2025).
  15. Dou, G.; Ying, X. Effect and satisfaction of direct drinking water equipment in middle and primary schools of Shanghai. Chin. J. Sch. Health 2018, 39, 1536–1539. [Google Scholar] [CrossRef]
  16. Hu, F.; Yang, J.; Li, P.; Qiu, W.; Hou, X.; Wei, X.; Wang, H.; Kauffman, A.E.; Xiao, S.; Liao, Z.; et al. Is direct-drinking water safe for children? An analysis of direct-drinking water quality and its risk factors in Shanghai elementary and middle schools. Int. J. Hyg. Environ. Health 2021, 231, 113650. [Google Scholar] [CrossRef] [PubMed]
  17. The People’s Government of Pudong New Area. Overview of Pudong New Area. Available online: https://english.pudong.gov.cn/2025-01/26/c_857515.htm (accessed on 29 May 2025).
  18. Kenney, E.L.; Gortmaker, S.L.; Cohen, J.F.; Rimm, E.B.; Cradock, A.L. Limited School Drinking Water Access for Youth. J. Adolesc. Health 2016, 59, 24–29. [Google Scholar] [CrossRef] [PubMed]
  19. Patel, A.I.; Hecht, C.E.; Cradock, A.; Edwards, M.A.; Ritchie, L.D. Drinking Water in the United States: Implications of Water Safety, Access, and Consumption. Annu. Rev. Nutr. 2020, 40, 345–373. [Google Scholar] [CrossRef]
  20. Zhu, Y.S.; Zheng, L.; Zheng, W.W.; Zheng, R.; Wang, Y.J.; Hu, B.Q.; Yang, M.J.; Zhao, Y.J. Occurrence and Distribution of Organophosphate Flame Retardants in Tap Water System-Implications for Human Exposure from Shanghai, China. Toxics 2024, 12, 696. [Google Scholar] [CrossRef]
  21. DB/T 1091-2025; Shanghai Bureau Market Superintend Management. Drinking Water Quality Standards. Standards Press of China: Beijing, China, 2025.
  22. GB 5749-2022; National Bureau Market Superintend Management. Standard for Drinking Water Quality. Standards Press of China: Beijing, China, 2022.
  23. WHO. Guidelines for Drinking-Water Quality, 4th ed.; WHO Press: Geneva, Switzerland, 2011; pp. 176–230.
  24. Li, M.; Chen, J.; Finlayson, B.; Chen, Z.; Webber, M.; Barnett, J.; Wang, M. Freshwater Supply to Metropolitan Shanghai: Issues of Quality from Source to Consumers. Water 2019, 11, 2176. [Google Scholar] [CrossRef]
  25. Liu, Y.; Shu, S.; Wang, H.; Zhao, X.; Yan, Q. Big Data Analysis of Water Quality of Secondary Water Supply. Procedia Comput. Sci. 2019, 154, 744–749. [Google Scholar] [CrossRef]
  26. Pezeshki, H.; Hashemi, M.; Rajabi, S. Removal of arsenic as a potentially toxic element from drinking water by filtration: A mini review of nanofiltration and reverse osmosis techniques. Heliyon 2023, 9, e14246. [Google Scholar] [CrossRef]
  27. Guo, H.; Li, X.; Yang, W.; Yao, Z.; Mei, Y.; Peng, L.E.; Yang, Z.; Shao, S.; Tang, C.Y. Nanofiltration for drinking water treatment: A review. Front. Chem. Sci. Eng. 2022, 16, 681–698. [Google Scholar] [CrossRef]
  28. Ling, F.; Whitaker, R.; Lechevallier, M.W.; Liu, W.T. Drinking water microbiome assembly induced by water stagnation. ISME J. 2018, 12, 1520–1531. [Google Scholar] [CrossRef]
  29. Camper, A.; Burr, M.; Ellis, B.; Butterfield, P.; Abernathy, C. Development and structure of drinking water biofilms and techniques for their study. J. Appl. Microbiol. 1998, 85 (Suppl. S1), 1S–12S. [Google Scholar] [CrossRef] [PubMed]
  30. Wang, M.; Zhang, Y.; Niu, Z.; Miao, Q.; Fu, W. Study on the distribution characteristics and metabolic mechanism of chlorine-resistant bacteria in indoor water supply networks. Environ. Pollut. 2023, 328, 121640. [Google Scholar] [CrossRef] [PubMed]
  31. Hu, X.; Wang, W.; She, Q.; Zhao, Y. Hygiene status of direct drinking water in primary and middle schools in Pudong New Area of Shanghai in 2016. Occup. Health 2018, 34, 1255–1257. [Google Scholar] [CrossRef]
  32. Levesque, B.; Lavoie, M.; Joly, J. Residential water heater temperature: 49 or 60 degrees Celsius? Can. J. Infect. Dis. 2004, 15, 11–12. [Google Scholar] [CrossRef]
  33. Spinks, A.T.; Dunstan, R.H.; Harrison, T.; Coombes, P.; Kuczera, G. Thermal inactivation of water-borne pathogenic and indicator bacteria at sub-boiling temperatures. Water Res. 2006, 40, 1326–1332. [Google Scholar] [CrossRef]
  34. Gu, H.; Gong, Y.; Li, Z.; Zhang, Y.; Wu, J.; Wang, Y.; Ni, M.; Zhang, J.; Jiang, H. Contribution of direct-drinking water to calcium and magnesium and the influence on the height in school-age children. Front. Nutr. 2024, 11, 1434952. [Google Scholar] [CrossRef]
  35. Liu, X.; Shu, S.; Yang, K.; Wang, T.; Geng, B. Intelligent Management of Secondary Water Supply Systems in Downtown Shanghai. Procedia Comput. Sci. 2019, 154, 206–209. [Google Scholar] [CrossRef]
  36. Elbel, B.; Mijanovich, T.; Abrams, C.; Cantor, J.; Dunn, L.; Nonas, C.; Cappola, K.; Onufrak, S.; Park, S. A water availability intervention in New York City public schools: Influence on youths’ water and milk behaviors. Am. J. Public. Health 2015, 105, 365–372. [Google Scholar] [CrossRef]
  37. GB/T 5750-2023; National Bureau Market Superintendent Management. Standard Examination Methods for Drinking Water. Standards Press of China: Beijing, China, 2023.
Water 17 01717 g001
Figure 1. Modes of school direct-drinking water in Shanghai.
Figure 1. Modes of school direct-drinking water in Shanghai.
Water 17 01717 g001
Water 17 01717 g002
Figure 2. Distribution of participating schools on the map.
Figure 2. Distribution of participating schools on the map.
Water 17 01717 g002
Water 17 01717 g003
Figure 3. Facilities with nanofiltration and hot water system.
Figure 3. Facilities with nanofiltration and hot water system.
Water 17 01717 g003
Table 1. Key Components regarding direct-drinking water access among primary, middle, and high schools in central and surrounding areas.
Table 1. Key Components regarding direct-drinking water access among primary, middle, and high schools in central and surrounding areas.
Total Samples
n (%)		School TypeSchool Location
Primary Schools
n (%)		Middle Schools
n (%)		High Schools
n (%)		p Value *Central AreaSurrounding Areap Value *
Water dispensers’ characteristics and features
    Modes of water treatment 0.072 0.172
        Nanofiltration135 (80.8)76 (86.4)34 (73.9)25 (75.8) 61 (84.7)74 (77.9)
    Reverse osmosis16 (9.6)4 (4.5)8 (17.4)4 (12.1) 7 (9.7)9 (9.5)
    Barreled/bottled drinking water13 (7.8)8 (9.1)3 (6.5)2 (6.1) 2 (2.8)11 (11.6)
    Mixed3 (1.8)0 (0)1 (2.2)2 (6.1) 2 (2.8)1 (1.1)
    Water temperature set in 20 °C to 40 °C33 (19.8)20 (22.7)8 (17.4)5 (15.2)0.67910 (13.9)23 (19.8)0.097
    Clean and functioning122 (73.1)67 (76.1)33 (71.7)22 (66.7)0.56349 (68.1)73 (76.8)0.205
    Posting usage prompts90 (53.9)41 (46.6)28 (60.9)21 (63.6)0.13239 (54.2)51 (53.7)0.951
    Usage of non-slip or waterproof materials around137 (82.0)72 (81.8)40 (87.0)25 (75.8)0.44060 (83.3)77 (81.1)0.704
Water dispensers’ location and placement
    Coverage of key high-traffic areas152 (91.0)78 (88.6)43 (93.5)31 (93.9)0.53269 (95.8)83 (87.4)0.058
    Average less than 45 students served by per faucet115 (68.9)57 (64.8)31 (67.4)27 (81.8)0.19149 (68.1)66 (69.5)0.854
Water dispensers’ upkeep and maintenance
    Frequency of water quality testing 0.069 0.010
        More than or monthly42 (25.1)18 (20.5)14 (30.4)10 (30.3) 26 (36.1)16 (16.8)
        Monthly23 (13.8)7 (8.0)9 (19.6)7 (21.2) 11 (15.3)12 (12.6)
        Less than monthly but at least twice a year83 (49.7)54 (61.4)18 (39.1)11 (33.3) 31 (43.1)52 (54.7)
        Seldomly tested or not19 (11.4)9 (10.2)5 (10.9)5 (15.2) 4 (5.6)15 (15.8)
    Training for school personnel158 (94.6)82 (93.2)44 (95.7)32 (97.0) 6395
    Frequency of dispenser cleaning 0.035 0.689
        More than or monthly26 (15.6)9 (10.2)12 (26.1)5 (15.2) 10 (13.9)16 (16.8)
        Monthly39 (23.4)20 (22.7)9 (19.6)10 (30.3) 18 (25.0)21 (22.1)
        Less than monthly but at least twice a year86 (51.5)54 (61.4)20 (43.5)12 (36.4) 39 (54.2)47 (49.5)
        Seldomly tested or not16 (9.6)5 (5.7)5 (10.9)6 (18.2) 5 (6.9)11 (11.6)
Water education and promotion
    Public display of water quality testing results134 (80.2)72 (81.8)37 (80.4)25 (75.8)0.75764 (88.9)70 (73.7)0.015
    Regular activities for students 126 (75.4)68 (77.3)35 (76.1)23 (69.7)0.68553 (73.6)73 (76.8)0.631
Total167 (100)88 (52.7)46 (27.5)33 (19.8) 72 (43)95 (57)
Note: * means Pearson chi-square tests.
Table 2. Levels of the water quality parameters in school direct-drinking water and tap water.
Table 2. Levels of the water quality parameters in school direct-drinking water and tap water.
Total Bacteria Count
(CFU/100mL)		Arsenic
(mg/L)		Aluminum
(mg/L)		Zinc
(mg/L)		Hardness
(mg/L)		pHCOD
(mg/L)		TDS
(mg/L)		Total Chlorine
(mg/L)		Turbidity
(NTU)		Temperature
(Degrees Celsius)
Direct drinking water
(Outlets)
n = 30		MINNDNDNDND1.06.940.3413.0-0.1017.0
MAX3200.00100.040.261237.581.36210-0.1894.0
MEAN31.40.00060.010.0570.17.310.87120-0.1347.9
MEDIANNDNDND0.031047.401.26185-0.1238.5
D.F.40%20%27%83%-------
Tap water
(Inlets)
n = 23		MINNDNDNDND1227.421.522170.090.10-
MAX17.00.00200.060.201337.731.962740.820.52-
MEAN2.10.00060.020.021277.601.772530.200.15-
MEDIANNDNDNDND1257.601.842570.130.12-
D.F.26%22%43%30%- ----
p Value ** 0.1160.8190.119<0.001<0.001<0.001<0.001<0.001-0.771-
Local standards [21]500.010.151.02506.5–8.525000.050.5
WHO guideline value [23]-0.010.1 a4.0 b200 c6.5–8.5 d-600 e0.2 f0.3 g-
Notes: ND means not detected; D.F. means detection frequency; ** means Mann–Whitney U test; a means no health-based guideline value, but the presence of aluminium at concentrations in excess of 0.1–0.2 mg/l often leads to consumer complaints as a result of deposition of aluminium hydroxide floc and the exacerbation of discoloration of water by iron; b means no health-based guideline value, but zinc imparts an undesirable astringent taste to water at a taste threshold concentration of about 4 mg/L (as zinc sulfate); c means no health-based guideline value, and though consumers tolerate water hardness in excess of 500 mg/L, water with a hardness above approximately 200 mg/L may cause scale deposition in the treatment works, distribution system, and pipework and tanks within buildings; d means no health-based guideline value has been proposed for pH, but it is usually in the range 6.5–8.5 depending on the composition of the water and the nature of the construction materials used in the distribution system; e means no health-based guideline value has been proposed for TDS, but the palatability of water with a TDS level of less than about 600 mg/L is generally considered to be good; f means the minimum residual concentration of chlorine should be 0.2 mg/L at the point of delivery; g means no health-based guideline value, but surface water treatment systems that achieve less than 0.3 NTU prior to disinfection will have demonstrated that they have significant barriers against pathogens that adsorb to particulate matter.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Zhu, Y.-S.; Hu, B.-Q.; Zheng, R.; Wang, Y.-J.; Zheng, W.-W.; Yang, M.-J. Survey of School Direct-Drinking Water Access for Children and Youth in Shanghai, China. Water 2025, 17, 1717. https://doi.org/10.3390/w17111717

AMA Style

Zhu Y-S, Hu B-Q, Zheng R, Wang Y-J, Zheng W-W, Yang M-J. Survey of School Direct-Drinking Water Access for Children and Youth in Shanghai, China. Water. 2025; 17(11):1717. https://doi.org/10.3390/w17111717

Chicago/Turabian Style

Zhu, Yuan-Shen, Bing-Qing Hu, Rong Zheng, Ya-Juan Wang, Wei-Wei Zheng, and Min-Juan Yang. 2025. "Survey of School Direct-Drinking Water Access for Children and Youth in Shanghai, China" Water 17, no. 11: 1717. https://doi.org/10.3390/w17111717

APA Style

Zhu, Y.-S., Hu, B.-Q., Zheng, R., Wang, Y.-J., Zheng, W.-W., & Yang, M.-J. (2025). Survey of School Direct-Drinking Water Access for Children and Youth in Shanghai, China. Water, 17(11), 1717. https://doi.org/10.3390/w17111717

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop