INTRODUCTION
The current domestic water situation
Domestic water refers to the water utilized in households for essential activities such as drinking, cooking, bathing, washing, and gardening It encompasses both potable and non-potable water supplied by public water systems as well as self-supplied sources Self-supplied water is often drawn from private wells or collected rainwater stored in cisterns.
In recent years, concerns about water quality and domestic water supply have intensified among scientists, managers, distributors, and users Many individuals express discomfort with the water currently available, leading to the adoption of various treatment methods, from homemade filters to advanced purification systems like RO and Kangaroo Additionally, bottled water has become a common alternative However, this raises two significant issues: the effectiveness and necessity of prefilled and RO-filtered water, and the social justice implications for families unable to afford bottled water or modern filtration systems, who are left to rely on water that may not meet quality standards, potentially jeopardizing their health.
The World Health Organization (WHO) reports that trachoma causes blindness in six million individuals, with over 150 million requiring treatment Water-related pathogens and diseases, including dysentery, cholera, and skin infections, are rapidly increasing in both developed and developing nations According to Global Health statistics from Harvard University, the impact of these diseases is significant and growing.
According to the World Bank, approximately 4 billion cases of diarrhea occur annually, resulting in the deaths of 2.2 million people, primarily children under five years old, which translates to a child dying every 15 seconds This alarming statistic represents around 15% of all child fatalities in developing countries In Vietnam, water quality management remains inadequate, with a fragmented approach that lacks focus and expansion across many localities.
Hanoi, the largest city in Vietnam, faces significant concerns regarding domestic water quality, prompting scientists and residents alike to seek solutions In response to the city's rapidly growing demand, numerous water treatment plants have been established; however, many Hanoians fear the potential health risks associated with unsafe water Dr Pham Hung Viet, Director of the Center for Environment Technology Research and Sustainable Development, highlighted that treated water still contains arsenic, manganese, and chlorine levels exceeding both Vietnamese and WHO standards Notably, only the water from Ngoc Ha street in Ba Dinh District meets the acceptable arsenic level of under 0.01 mg per liter, while other plants such as Phap Van and Thanh Tri continue to supply water with high arsenic concentrations While studies on water quality have been conducted, they primarily focus on Hanoi's densely populated inner city, with less attention given to suburban areas due to the higher costs associated with research.
Thuy Xuan Tien is a quaint commune located in Chuong My District, Hanoi, comprising nine hamlets: Xuan Thuy, Xuan Linh, Xuan Sen, Xuan Long, Xuan Trung, Go Cao, Tien An, Tien Truong, and Tri Thuy The commune is currently undergoing development, showcasing its commitment to progress and growth.
The rapid economic growth in the area has led to an increase in the concentration of offices, schools, and supermarkets, significantly raising the local demand for domestic water While groundwater serves as the primary source of water, prolonged extraction and pollution from domestic sewage have compromised its quality in certain locations, resulting in elevated levels of contaminants and the presence of harmful organisms Currently, there is a lack of comprehensive studies to assess the quality of water reserves, as annual observations remain superficial and do not provide detailed analyses or results to the community Therefore, it is essential to conduct in-depth research to enhance water quality and implement effective solutions for ensuring access to clean water for local residents.
The objective of this study is to assess the quality of domestic water in Thuy Xuan Tien commune, Chuong My district, Hanoi, Vietnam This research aims to raise awareness among users about water quality issues and to propose effective solutions for ensuring access to clean water for the local community.
Literature Review
Domestic water, also known as potable water, is characterized by its acceptable physical, chemical, and bacteriological quality, ensuring safety for drinking and cooking purposes (WHO, 2004) According to the World Health Organization, water is considered safe for consumption if it does not pose significant health risks over a lifetime It is essential to prioritize efforts to maintain the highest quality of drinking water for the well-being of the population.
Many individuals lack access to safe drinking water, exposing them to high contamination levels that can lead to various diseases (Mensah Thesis, 2011) Contaminated water often contains pollutants exceeding WHO drinking water quality standards, posing serious health risks when consumed (Cunningham).
1999) Due to the open accessibility of surface water and hand-dug well, they easily receive foreign materials from various sources which negatively impact on the quality of the water
In Vietnam, the state of rural domestic water supply is concerning due to environmental pollution and the improper treatment of wastewater from industrial and production facilities As of 2016, 67% of households in rural areas rely primarily on wells, underground aquifers, rivers, streams, lakes, and rainwater for their water supply, according to the Centre for Water and Sanitation The province has established 110 water supply projects in rural regions, with six managed by public service units, two by corporate managers, and 102 under local self-management.
There are 85,900 small water supply projects, including dug wells and water tanks, driven by community self-realization and exploitation The Ministry of Health regulates centralized water supply projects to ensure compliance with national water quality standards (QCVN02: 2009) Management units are required to sample water periodically every 3-6 months and send it to authorized bodies for testing The test results indicate the testing unit, but management units are not mandated to submit clean water results to oversight agencies, complicating the monitoring of facility operations.
5 piped timely remediation, water treatment while providing no guarantee of health indicators to the user or not
The Center for Clean Water and Rural Environmental Hygiene is tasked with managing water quality oversight and conducting probabilistic sampling inspections However, the program's funding is limited, resulting in only a few hundred samples being collected annually from various sources, including centralized water supply facilities, gravity-fed systems, and community wells (Thu Nguyet, 2014).
According to the Ministry of Agriculture and Rural Development (MARD), 84.5% of rural residents in the country have access to clean water The Southeast region boasts the highest percentage at 94.5%, followed by the Red River Delta at 91% and the Mekong River Delta at 88% In contrast, the North Central region has the lowest access to clean water at 81%, despite having the second highest number of rural households nationwide.
In Hanoi, 35.5% of rural residents utilize drinking water that meets new standards, with only 7.7% sourced from the city's centralized water supply, while the remainder relies on the urban water supply system and individual household water filters (Vo Hung, 2016) To ensure comprehensive water quality assessment, traditional chemical indicators must be expanded to include physical, biological, and ecological parameters, recognizing that fresh water quality is influenced by both natural and anthropogenic factors such as land use, erosion, and deforestation Addressing these challenges often requires local monitoring and protection, alongside national and international efforts for issues with transboundary implications (International Conference on Water and the Environment Report, 1992).
STUDY GOAL AND SPECIFIC OBJECTIVES
Study goal and objectives
Goal: The goal of this project is to assess the water quality of local people in Thuy Xuan
Tien from the various source
Investigating the situation of domestic water in study area
+ The form of domestic water using in Thuy Xuan Tien commune;
+ The demand of clean water use for local people
Assessing the quality of domestic water in Thuy Xuan Tien commune through the indicators collected and measured in the lab in September:
+ Characteristics reason: odor, pH, hardness
To enhance domestic water quality for local residents, it is essential to propose effective technological solutions and management strategies that optimize the exploitation and use of water resources in the study area.
METHODOLOGY
Study area
Figure 3.1 The map of Chuong My District
Thuy Xuan Tien commune, located in the mountainous region of Chuong My district, Hanoi, covers an area of 1,191.51 hectares and has a population of 16,654 residents as of 2015 It is situated at geographic coordinates 20°53'10"N and 105°35'4"E, and is divided into nine rural communes: Xuan Thuy, Xuan Long, Xuan Linh, Xuan Trung, Tri Thuy, Tien An, Go Cao, Xuan Sen, and Tien Truong.
In recent years, rapidly increasing population and economic and educational developments of the city brought a huge stress on natural resources including ground
Economic growth is driving a shift in the economic structure, leading to increased investment in infrastructure such as transportation systems, post offices, and schools As development accelerates, the demand for clean water among individuals, businesses, and educational institutions is rising However, water resources are not being effectively managed or quality-assured, making it crucial to treat and enhance the quality of domestic water to support economic development Currently, there is a lack of research focused on assessing and improving domestic water quality in the commune, with most residents relying on electric pumps for water extraction, while only a few utilize hand pumps.
Thuy Xuan Tien is a commune characterized by varying living standards and poor housing conditions among its residents A study was conducted to assess water quality by collecting sixteen samples from electric pumps, the primary source of domestic water in the area These samples were tested at the Center of Laboratory and Practice of Vietnam Forestry University, focusing on selected physical and chemical parameters The results were then compared with national and international water quality standards, including QCVN 01: 2009/BYT, QCVN 02: 2009/BYT, and the Australian Drinking Water Guidelines (ADWG, 2006) Additionally, a field survey was carried out using random cluster sampling to gather data on the overall physical quality of water, with findings illustrated through graphs created in MS Excel.
Interviewing
The project conducted interviews with 80 households across nine hamlets: Xuan Thuy, Xuan Long, Xuan Linh, Xuan Trung, Tri Thuy, Tien An, Go Cao, Xuan Sen, and Tien Truong The aim was to determine the primary water sources utilized in the region and to assess the community's awareness of the significance of using clean water.
Therefore, investigating the amount of domestic water in the whole commune and the demand of local people for using clean water.
Sampling methods
When analyzing water quality, it is crucial to select indicators that reflect the specific natural conditions and socio-economic development of the region Key indicators for assessing water safety include iron, manganese, odor, pH, hardness, fluoride, and chloride, as they play significant roles in determining the health risks associated with water consumption Heavy metals and other elements such as fluoride and chloride directly impact human health, making them essential for analysis Water samples should be collected directly from wells or extraction points to ensure accurate assessment.
The request of water sampling method appropriate for each indicator:
- Water samples are taken directly from the water department of the family with the following procedure:
- Step 1: Unscrew the drain hose, the water runs out about 5-6 minutes to remove all the water available in the tube
To prepare water samples for analysis, use clean polyethylene plastic bottles with a capacity of 2-3 liters to ensure comprehensive parameter analysis Depending on the specific criteria, apply appropriate preservation methods; for heavy metal analysis, such as iron (Fe) and manganese (Mn), add HNO3 acid to the samples It's essential to document all relevant information, including sample symbols, sampling locations, dates, weather conditions, and the names of samplers Finally, securely pack the samples in crates for transportation to the laboratory for analysis.
When shipping samples, it is crucial to meticulously document all relevant information, including locations, dates, and the type of water storage, both on the bottles and in accompanying notes.
- Also, borrowed some tools to measure indicators such as pH, temperature at the time of sampling locations and to get the most accurate results
Using litmus paper to measure, put it directly into the water sample Wait about 10 seconds until the displayed results on paper, and recorded the results
Using hand-held meter HI98129, embedded directly locomotive into water, wait about
20 seconds until the displayed results and recorded parameters to be measured.
The sampling locations
To assess water quality in Thuy Xuan Tien commune, a randomized sampling study was conducted across 16 sites in five densely populated and economically developing areas: Xuan Thuy, Xuan Trung, Xuan Sen, Xuan Long, and Xuan Linh The sampling included a total of 15 water samples, categorized into four types of water use: 7 from digging wells, 4 from drilling wells, 2 from pumping water, and 2 from rainwater.
Sampling locations are described in Table 3.1:
Table 3.1 The sampling sites locations
Household owner Water source Location Date
1 S01 Nguyen Van Hau Drilling Well Xuan Thuy 01/09/16
2 S02 Pham Thi Tha Rain Water Xuan Thuy 01/09/16
3 S03 Nguyen Thi Thanh Van Digging Water Xuan Thuy 01/09/16
4 S04 Trinh Thi Bay Digging Well Xuan Sen 01/09/16
5 S05 Nguyen Van Quang Digging Well Xuan Trung 01/09/16
6 S06 Nguyen Van Tri Digging Well Xuan Sen 01/09/16
7 S07 Hoang Thi Nu Drilling Well Xuan Linh 01/09/16
8 S08 Chu Thi Binh Drilling Well Xuan Long 01/09/16
9 S09 The Armed Police College Digging Well Xuan Thuy 02/09/16
10 S10 Vu Duy Thinh Digging Well Xuan Linh 02/09/16
11 S11 Dang Thi May Digging Well Xuan Sen 02/09/16
12 S12 Khuat Van Khai Digging Well Xuan Sen 02/09/16
13 S13 Lai Thi Thuy Drilling Well Xuan Long 02/09/16
14 S14 Be Tong Apartment Pumping Water Xuan Trung 02/09/16
15 S15 Trinh Xuan Hien Rain Water Xuan Sen 02/09/16
16 S16 J106 Nursery School Pumping Water Xuan Thuy 02/09/16
Analytical methods in laboratory
a Measure the total amounts of Fe in the water
Determination of Fe total by sunfoxalixilic acid reagent, as this is highly selective reagent for Fe and mitigate interference agents of some divalent metals in the water
Oxidation of iron in the sample is completely on form Fe 3+ This ion reacts with acid reagents sunfoxalixilic alkaline forming yellow complex
- Step 1: Get 0; 1; 3; 5; 10 ml Fe 3+ concentration of 1mg / ml pour into to 100ml volumetric flask and denoted respectively S01, S02, S03, S04, S05
- Step 2: Add about half of the amount distilled water in the bottle, 2 ml NH4Cl solution, 2ml Sunfoxalixilic acid solution and 2 ml NH3 solution, and shake
In Step 3, distilled water is added to the marked norms, resulting in Fe 3+ concentrations in the flask of 0, 0.01, 0.05, and 0.1 mg/l After a duration of 5 minutes, the optical density of the solution is measured at a wavelength of 430 nm using UVIS.
- Step 4: Determine the maximum absorbance and road construction standards show a correlation between concentration and optical density measured by the equation:
Y = Ax + B Y: The amount of Fe in the sample
Analysis method for the sample and calculating results
Due to the low concentration of iron (Fe) in domestic water, sample enrichment is necessary The process involves taking 1 liter of concentrated water samples and reducing it to 80-300 ml, which represents the enriched form Following this, standard road construction templates are applied for further analysis The results are calculated using the equation Y = ax + b.
C1: The following concentration calculated from the calibration curve (mg / l) V1: the volumetric flask (100ml)) b Measuring the total chloride in the water
To analyze water samples, take 100 ml (Va) and place it in a conical flask or beaker Adjust the pH to a range of 5 to 9.5 using HNO3 or NaOH, recording the volume used; if the pH is below 5, it is advisable to use Na2CO3 for adjustment Next, add 1 mL of K2CrO4 and perform a titration by adding AgNO3 solution drop by drop until the solution changes to a brownish-red color, noting the volume of AgNO3 used Finally, add a drop of NaCl to observe that the color disappears.
Do the same for white (distilled water sample) and record the volume of solution AgNO3 does not exceed 0.2ml
Chloride concentrations in the water is calculated by milligrams / liter by the formula:
CCL = (Vc - Vb) C35453 / Va CCL: local chloride concentration in mg / l
Va: volume of the sample in ml (100ml)
To determine the total hardness in water, measure the volume of AgNO3 solution used to titrate the blank (Vb) and the volume used to titrate the sample (Vc), both in milliliters Additionally, note the concentration of the AgNO3 solution used for titration (C) in mg/l These measurements are essential for calculating the total hardness of the water sample.
Samples must be taken labs on polyethylene bottle, do not use average glass
- Analysis of the samples as soon as possible, if the samples need to be stored before distribution the sample area to keep in 2 ~ 6 o C
To ensure accurate results, it is essential to neutralize the acidified sample with a specific volume of 2M NaOH When calculating results, one must consider any dilution effects caused by the addition of acid or alkali to both the sample and the test portion.
- Shake the bottle and sample preservation must make sure that the pharmaceutical form of homogeneous binhf taking part samples analyzed
To prepare a solution for titration, smoke 10 ml of 10 mmol CaCO3/l into a 250 ml flask and dilute it to 50 ml with distilled water Proceed with the titration process as outlined Finally, measure the total concentration of manganese in the water sample.
Get two conical flask, 250 ml capacity (if doing multiple samples, for example 8 + 1 samples are taken for 8 conical flask)
To analyze the water sample, pour 100 ml into a conical flask and add 1 ml of sulfuric acid and 1 ml of 10% silver nitrate Boil the mixture until the volume reduces to 50 ml, then filter to remove the precipitate and rinse with pure water to restore the original volume of 100 ml Continue boiling and add 10 ml of saturated potassium persulfate, then boil for a few more minutes until the solution turns pink.
To prepare the solution, add 5 ml of 75% sulfuric acid and 10 ml of saturated potassium persulfate to a second conical flask Boil the mixture for an additional minute, then allow it to cool before diluting with 100 ml of distilled water.
After allowing both conical flasks to cool, slowly add a 0.01 N solution of potassium permanganate from a burette into the second flask while gently shaking until the color matches that of the water sample Record the volume of potassium permanganate used (n) to determine the total fluoride concentration in the water.
Step 1: Fill a 20ml (beaker/small plastic container) about half-way with the water sample (about 10ml)
Step 2: Add 20 hydrochloric acid drops The pH value must be below 1 Step 3: Remove one fluoride test disc from ziplock bag Close bag immediately Step 4: Pierce the round test disc in the middle with the enclosed needle! Step 5: Throw test disc into the water sample and submerge completely Step 6: after 5 - 7 minutes the test disc is saturated with the solution, i.e it does not absorb any more liquid At the latest 2 minutes after saturation remove the test disc from the sample and compare the size of the bleached zone with the disc color scale This test will give you a reaction when the sample water has at least 2 parts per million of fluoride Otherwise no changes will be observed
RESULTS
Current use of domestic water in Thuy Xuan Tien commune
4.1.1 The main water resource of local people
In communal living across various regions, water sources are categorized into three types: groundwater, surface water, and rainwater Groundwater is the most frequently utilized resource, while some households also harness natural rainwater as a supplementary source, complementing their primary water supply.
Groundwater is extracted primarily through wells and dug wells; however, surveys and interviews indicate that in some regions, these resources are contaminated with wastewater and insufficient for sustaining life during dry seasons The situation worsens as urbanization increases concrete surfaces, limiting natural land Groundwater can often be used directly without treatment or with simple filtration systems, as well as modern purification systems like RO or Kangaroo Research suggests that in areas with limited groundwater reserves, it is crucial to exploit and use these resources rationally.
Rainwater, collected in tanks and through self-built systems, is primarily used for drinking purposes A study conducted across eight areas in Tien Thuy Xuan commune, based on 80 surveys, reveals the utilization rates of various water sources, including pumped water, dug wells, drilled wells, and rainwater, as illustrated in Table 4.1 below.
Table 4.1 Water source of domestic use in Thuy Xuan Tien commune
No Source of water supply Total Percentage (%)
5 Digging/Drilling wells/Pumping water + Rain water
Through Table 4.1 shows that the proportion of water use is greatest gieesgn training
The process of digging wells is straightforward and cost-effective, typically involving depths of 6 to 10 meters and diameters ranging from 0.8 to 1.2 meters Water is extracted for direct use or filtered before consumption However, during the dry season, many wells experience reduced water levels and often produce turbid water, failing to meet the daily needs of residents, particularly in areas along Highway 6 (Tien Truong village) and Ho Chi Minh Road (Xuan Sen village, Xuan Trung).
In a survey of 80 households, only 28% reported using well water, primarily influenced by their economic conditions Some families resort to drilling wells to access shallow groundwater However, many users have noted that well water frequently contains higher levels of iron and occasional debris compared to tap water.
In the Be Tong apartment building area (Xuan Trung), tap water is primarily utilized for living and learning activities, including those at J106 Nursery School, which relies on treated water sourced from 60m deep wells Despite this, only 11% of households in the region use the centralized tap water system, as many prefer to dig their own wells for water supply This trend is particularly evident among households with land, while residents of apartment buildings, schools, and factories tend to rely on centralized sources for quality assurance Expanding the centralized clean water model is essential to improve access and ensure water quality for a larger portion of the community.
Among the surveyed households, none rely solely on rainwater as their primary drinking water source due to its insufficient availability Only 4% of respondents, or 3 households, utilize rainwater in conjunction with other sources such as wells or tap water, where rainwater is typically purified for family consumption Additionally, 4% of the 80 households interviewed depend on water wells and drilling as their primary water source, highlighting the common practice of combining different water sources for household needs.
Table 4.2: The assessment of local people about the amount of domestic water
The amount of domestic water Quantity Percentage (%)
In a recent survey, 32.5% of households reported insufficient water supply during the dry season, prompting them to seek alternative solutions Many resort to purchasing bottled water from supermarkets, although the quality remains uncertain Others rely on water from neighboring households, but this option becomes challenging when the entire village faces shortages, leaving them with no choice but to buy water To combat this issue, some households are adopting water-saving practices, such as reusing water whenever possible, which not only ensures adequate supply but also promotes conservation.
4.1.3 Water quality and treatment equipment
Table 4.3: The assessment of local people about domestic water quality
In a survey of 80 households, 59% reported using water for quality assurance, while 14% rated the water quality as average and 25% deemed it poor Consequently, 47% of households utilize water purification devices, with 24% employing RO filtration systems like Kangaroo, and others using simpler filters such as Korean King, Tan A, or homemade charcoal filters Despite concerns about water quality, 98% of respondents indicated that it has no impact on their health, with only 2% experiencing temporary issues like allergic rashes or skin peeling.
4.1.4 Demand for pumping water (centralized water supply)
Table 4.4: Demand of using pumping water
Demand for pumping water Quantity Percentage (%)
Need to use pumping water 20 25
Using pumping water combine with other water sources
In recent household surveys, over 25% of respondents indicated a need for centralized water supply quality, while 60% expressed a desire for a new water source but continue to rely on existing options due to concerns about water pricing, losses from power outages, and pipeline repairs Additionally, 15% of households reported no need for alternative water sources Notably, 88% of participants are willing to pay for higher water quality, indicating a strong interest in improved centralized water supply systems, while only 12% are satisfied with their current water sources These findings highlight a significant demand for enhanced water quality assurance in the future.
Table 4.5 Results of water sample wells analysis in Thuy Xuan Tien Commune (2016)
1 odour(*) No - - - - - - - - No No (a) Dispensable
4.2.1 Results of digging well samples analysis
To assess the quality of drilling wells, key parameters such as pH, hardness, total iron, fluoride, manganese, and chlorine were analyzed The findings from the analysis of seven digging well samples are presented in Table 4.5.
QCVN 01: 2008/BTNMT – National technical regulations on groundwater quality
QCVN 02: 2009/BYT – National technical regulations on water quality
(I) The maximum limit allowed: Apply for water supply facilities
The maximum limit permitted for the exploitation of individuals and households includes various methods such as piped water systems, simple handling techniques, wells, dug wells, rainwater tanks, and gravity flow pipes.
ADWG: Australia Drinking Water Guilines, 2006
(a) The value standard for the impact on human health
(b) The value standard for aesthetic influence / organoleptic
Comparing with standard values given in two regulations of Vietnam, ACVN 01:
In 2009, the National Technical Regulation on domestic water quality (NTR 02: 2009) indicated that five key parameters—Odour, Iron (Fe), and Fluoride (F)—were within permissible limits However, the analysis revealed that pH and hardness levels frequently exceeded regulatory standards, with many indicators falling outside acceptable ranges Detailed results are presented in Table 4.5, highlighting the concerning parameters of pH and total hardness, which will be further analyzed in subsequent sections.
The pH level of water indicates its acidity or alkalinity, with pure water having a neutral pH of 7 Water with a pH below 7 is classified as acidic, while a pH above 7 indicates basicity Typically, surface water has a pH range of 6.5 to 8.5, whereas groundwater generally has a pH of around 6.
The ideal pH for drinking water ranges from 6 to 8.5, as values below 4 or above 11 can negatively impact health While the human body can generally maintain a balanced pH, the pH level of domestic water has minimal health effects unless consumed directly over extended periods, which can affect the enzyme system Water with a pH below 6.5 may be corrosive, while pH levels above 8 can hinder chlorine disinfection and lead to undesirable taste issues High pH levels, particularly above 8.5, indicate hard water and may result in increased pH values due to concrete or cement pipe systems Low pH water (