Abstract
Access to safe drinking water, sanitation, and hygiene in Chad's cities, especially N'Djamena, is a persistent and significant challenge. This study aimed to assess current practices in water, sanitation, and hygiene in N'Djamena's third and ninth districts. We surveyed 395 households, conducted water source identification, and analyzed seven water samples at the National Water Laboratory. Temperature, ammonium, total coliforms, and aerobic flora values exceeded World Health Organization (WHO) guidelines. Ammonium and temperature averaged 0.7 mg/L and 30.1–31.93 °C, respectively. Bacterial contamination (>100 MPN/100 mL) exceeded the WHO's 0 MPN/100 mL guidelines, rendering the water unfit for consumption. Survey results indicate that 78.7% use hand pumps, 21.1% have tap water access, and 0.2% rely on rivers for water. Regarding toilets, 92.8% have traditional models, 2.9% have modern facilities, and 4.3% practice open defecation. 95% dispose of untreated wastewater into nature, with only 5% using septic tanks. For solid waste, 72% use illegal dumpsites, 18% rely on public services, and 10% burn waste. Finally, 95.5% of households wash their hands with clean water and soap after using the toilet. It is crucial to treat drinking water and implement proper hygiene and sanitation measures to safeguard the population's health in the studied area.
HIGHLIGHTS
Identification of gaps for targeted interventions.
Enhancement of public health and quality of life.
Information for more effective WASH policies and programs.
Foundation for mobilizing resources and partnerships.
Strengthening resilience in the face of water-related challenges.
INTRODUCTION
Access to safe drinking water, sanitation, and hygiene (WASH) has been recognized as a fundamental right by the United Nations General Assembly and the Human Rights Council in 2010 and 2015, respectively. Consequently, WASH has been at the forefront of development goals. The global targets for drinking water under the Millennium Development Goals (MDGs) were achieved in 2010, 5 years ahead of the 2015 target date, while the sanitation goal was not met. Water is a vital resource for human survival; its unavailability or poor quality can lead to numerous waterborne diseases (Lagnika et al. 2014). The source of drinking water and its treatment are crucial in the fight against waterborne diseases, as well as for overall well-being and productivity.
Furthermore, it is anticipated that nearly 3 billion people will lack access to freshwater by 2025, forcing them to live in water-stressed environments (Tran et al. 2016). As a result, diseases and deaths resulting from inadequate water and sanitation systems continue to burden the world, affecting both developed and developing nations. Approximately 27% of the global population is estimated to lack access to safe drinking water, with 2.3 billion people lacking adequate sanitation facilities (WHO 2020). Water-related diseases account for approximately 4 billion cases and result in 3.4 million deaths each year. About 88% of these deaths can be attributed to unsafe drinking water and inadequate sanitation (WHO 2020; Yeboah et al. 2022).
In some major African cities, there is an alarming proliferation of illegal household waste dumps along public roads, in vacant spaces, watercourses, and near residential areas (Sy et al. 2011; Mangoumbou et al. 2023). The WHO/UNICEF (2015) reveal that in sub-Saharan Africa, 32% of the population lacks access to clean water, and 70% lacks proper sanitation systems. According to the Unitied Nations (2015), the proportion of people using improved sanitation facilities increased from 24% in 1990 to 30% in 2015. Sanitation remains one of the major public health challenges in Africa. Furthermore, 28% of the population in sub-Saharan Africa practices open defecation, and 23% uses ‘unimproved’ sanitation facilities that do not ensure adequate hygienic separation of human waste and contact (WHO/UNICEF 2015). Due to this lack of sanitation, millions of people in Africa contract fecal–oral diseases, with diarrhea being the most common (Al-Ghamdi et al. 2009).
In Chad, according to the report from the Ministry responsible for Water and Sanitation presented on World Water Day 2023, access rates stand at 63% for clean water and 20% for sanitation services for the country's population. Most of these services are concentrated in urban areas. However, this rate hides disparities in the distribution of infrastructure types and access rates at the provincial level, as well as access inequalities between urban and rural populations. Health statistics from the Ministry of Health and Prevention (MHP) reveal that the lack of clean water and unfavorable hygiene conditions are the leading causes of mortality and morbidity in the population, especially in children aged 0–5 years.
According to the Fourth Household Living Conditions and Poverty Survey in Chad (INSEED 2018), 66.5% of households lacked appropriate sanitation facilities. The absence of toilets is more pronounced in rural areas at 8.3% compared to 17.5% in urban areas. Consequently, bacteriological contamination of water could be attributed to open defecation, one of the primary sources of water contamination by fecal matter, leading to most diarrheal diseases in children aged 0–5 years (WHO 2017). The vast majority, 88% of the population, lacks access to acceptable hygiene and sanitation conditions. As a result, waste disposal methods in urban areas are as follows: 50.4% of households resort to open dumping, 25.2% burn their waste, 10% use public dumps, and 14.4% opt for private waste collection services. Therefore, the primary objective of our study is to examine WASH practices in the third and ninth districts of N'Djamena, Chad.
MATERIALS AND METHODS
Study area description
Geographical location of the third and ninth arrondissements of the city of N'Djamena (Republic of Chad).
Geographical location of the third and ninth arrondissements of the city of N'Djamena (Republic of Chad).
Data collection
The present study offers a comprehensive analysis of data on scientific document consultations from 1977 to 2023, encompassing both qualitative and quantitative data. Qualitative sources include scientific documents, technical reports, and legislation pertaining to water, hygiene, and sanitation. A field survey was conducted using questionnaires aimed at women of reproductive age, utilizing the Kobo Toolbox software on Android smartphones.
In the study of the third and ninth districts in N'Djamena, ‘n’ represents the sample size, and ‘N’ is the number of households. ‘e’ signifies a 5% margin of error, and ‘1’ represents the probability of an event occurring. Researchers used on-site observations and indirect questioning to assess drinking water and sanitation infrastructure, hygiene practices, and amenities like toilets and faucets. Investigators met specific criteria and were fluent in Arabic and French. They received training in interview techniques and ethics. After the survey, discussions and interviews were held with key informants, including officials from the Water Supply Department, healthcare professionals, and community leaders. Seven samples (four from hand-operated pumps and three from tap water) of drinking water were collected, transported, and analyzed at the National Water Laboratory to assess the quality of water consumed by households, in accordance with the American Public Health Association standards (APHA-AWWA-WPCF 1994).
Ethical protocol
This research was approved by the National Bioethics Committee of Chad (CNBT) in August 2022. It included a detailed protection protocol outlining potential risks throughout the survey's lifecycle. Verbal consent was obtained from each participating respondent, particularly among women of reproductive age, aged 15–49 years, who were individually interviewed. All respondents were fully informed of the voluntary nature of their participation, as well as the confidentiality and anonymity of the information provided. Furthermore, respondents were informed of their right to refuse to answer any question or terminate the interview at any time, or even decline to participate in the survey entirely.
Statistical data analysis
The numerical data were analyzed using Microsoft Excel and SPSS software (v21) with the aim of generating graphical representations. Furthermore, the Spatial Analyst module of ArcGIS 10.3 was employed to create a precise map of the study area. It should be noted that all statistical analyses were conducted with a confidence level of 95%.
RESULTS AND DISCUSSION
Institutional framework for the management of basic WASH services
The institutional actors involved in the WASH sector in the two districts are as follows: the Departmental Delegation, the Water Supply Directorate, the Sanitation Directorate (SD), under the Ministry responsible for Water and Sanitation, the delegations from the MHP as well as the Ministry of Environment, Fisheries, and Sustainable Development (MEFSD), the District Delegations, various partners (NGOs, charitable and non-charitable associations, etc.), and the two municipal administrations.
Characteristics of the surveyed households
Out of the 395 households studied, those with children aged 0–5 years sharing both residence and meals were identified. Among them, 66% had finished primary education, 15% had completed secondary education, 3% had received vocational or university training, and 16% were illiterate. Furthermore, 56% of these households were involved in income-generating activities, 46% were homemakers, and 1% were employed women. Almost all, 99.9%, identified as Christians or Muslims, with a small 0.1% identifying as atheists.
Determining the size of the sample to be surveyed
A sample of 395 households was determined according to the formula by Cochran (1977) based on a projection from the General Population and Housing Census (RGPH) of 2009 to the year
At the district level, the sample size was allocated as outlined in Table 1.
Sample of households surveyed by district
Districts . | Names of neighborhood . | Households in 2018 . | Households surveyed . |
---|---|---|---|
Third district | Ambassatna, Ardep Djoumal, Djambalbarh, Gardolé1, Kabalaye, Sabangali | 10,691 | 144 |
Ninth district | Digangali, Gardolé 2, Kabé, Ngoumna, Ngueli, Toukra, Walia | 18,535 | 251 |
Total | 29,226 | 395 |
Districts . | Names of neighborhood . | Households in 2018 . | Households surveyed . |
---|---|---|---|
Third district | Ambassatna, Ardep Djoumal, Djambalbarh, Gardolé1, Kabalaye, Sabangali | 10,691 | 144 |
Ninth district | Digangali, Gardolé 2, Kabé, Ngoumna, Ngueli, Toukra, Walia | 18,535 | 251 |
Total | 29,226 | 395 |
Sources of water supply, accessibility, and means of transportation
To address potable water contamination, the Ministry, STE, district authorities, partners, and the community must collaborate on measures like proper chlorination, pipeline maintenance, and regular inspections.
Containers for transporting and storing drinking water come in various sizes, from 25-L jerry cans to 200-L plastic drums, clay jars, buckets, basins, and even refrigerators. Households employ different methods, ranging from carrying water on their heads or by hand to using pushcarts, tricycles, wheelbarrows, and sometimes motorcycles or cars. Regarding costs, 90% of households access water freely from charitable and private sources, while 10% pay 100 CFA francs (0.17 USD) for a 200-L drum of tap water. Notably, women (55%) and girls (35%) bear the primary responsibility for water collection, while men (4%) and boys (6%) are less involved. These findings align with a study in Bamako, Mali (Diawara et al. 2021), where 57.1% use carts or pushcarts, 35.7% use motorcycles, tricycles, or cars, and 7.2% carry water on their heads. Raising awareness and taking action to ensure equitable access to clean water is crucial for overall well-being and health. Implementing measures to reduce economic and gender disparities is imperative for achieving this goal.
Local potable water treatment methods
The primary objective of water treatment is to safeguard consumers' health by protecting them against pathogenic microorganisms, as well as unpleasant or potentially hazardous impurities. However, certain inefficient methods lead to the consumption of domestic water harmful to households' health (WHO 2017). Consequently, various water treatment techniques fail to eliminate all pathogenic microorganisms present in drinking water (Hèdible 2007), thereby exposing users to waterborne diseases such as typhoid fever, intestinal parasitic infections, and diarrhea.
Figure 5 highlights that 87.4 and 12.6% of the surveyed adult women in the ninth district use bleach and Aquatabs tablets, respectively, as their disinfection method, compared to 55 and 0.8% in the third district. Moreover, 34.1 and 7% of households in the third district use filtration, while in the ninth district, no water filtration techniques are employed (0%).
These analyses demonstrate that water treatment techniques such as filtration and sedimentation are not primarily used in the ninth district due to the households' low income, which limits the purchase of equipment like water filters, and a lack of knowledge about water treatment techniques. However, the majority of the surveyed households consider water treatment before consumption as crucial. As a result, the issue of water quality for household consumption in the third and ninth districts is critical.
Our findings corroborate those obtained by Diop et al. (2021) in their study on water supply in the commune of Parcelles Assainies in Dakar, Senegal. Bleach stands out as the primary water treatment method used (66.7%), followed by Aquatabs (32.2%). Filtration and sedimentation are also noteworthy, representing 11.1 and 10.8% of the water treatment methods, respectively. These results contrast with those observed in rural areas, where the predominant water treatment techniques are primarily filtration (30%), sedimentation (17%), and water chlorination (15%), as reported in the study conducted by Diop et al. (2019).
Similarly, Biembe (2019) demonstrates that in certain neighborhoods in Yaoundé, Cameroon, 63% of households use multi-stage filters, 13% practice chlorination, and 8% opt for sedimentation. The treatment of drinking water varies depending on the source, contaminants, and available resources. Combinations of methods are employed to ensure safe drinking water.
Local appraisals of drinking water quality: a criterion for assessing the potability of water
Taste and smell of the water
Although water is often perceived as tasteless and odorless, several factors can alter our perception of these characteristics (Risso et al. 2019). Dissolved ions, contaminants, as well as chemical compounds used in water treatment, and even microbial activity can introduce nuances in the taste and smell of water (Dietrich & Burlingame 2020). Individual sensitivity also plays a significant role in how we perceive these nuances, adding complexity and further interest to the study of the sensory properties of water (Agrawal & Schachner 2023).
The flavors and odors of water generally pose no health risks; however, they can serve as potential indicators of contamination, whether it is of chemical or biological origin (Piccardo et al. 2022). An unpleasant taste or odor could signify the need for a more thorough analysis (Hawko et al. 2021). This feature could be of crucial importance from the user's perspective, particularly concerning the quality of water intended for consumption (Carrard et al. 2019).
Figure 6 displays the proportion of adult women surveyed about water quality based on their taste perception. Out of the adult women surveyed, 59.9% reported that the water is good to drink, with 23.1% specifying it as moderately good. Conversely, 13.7, 2.3, and 1% of the women surveyed believed that the water they drink is salty, bad, and relatively unpleasant, respectively.
Figure 7 reveals that a proportion of 73.1% of the adult women surveyed perceived the consumed water to have a good odor. However, 19.3 and 3.8% of the adult women surveyed reported that the consumed water was disgusting, bad, and salty, respectively. This evaluation of drinking water quality is one of the reasons why these adult women must carefully choose their water source.
These study findings corroborate those discovered by Dimitri Miriac et al. (2020) in the Lokossa Commune, Southwest Benin, where 68–77% of consumers appreciate water due to its organoleptic quality (taste and odor). However, they differ from the ones found by Diop et al. (2021) concerning water supply in the Parcelles Assainies Commune of Dakar, Senegal. In that study, 63–68% of consumers frequently refrain from consuming tap water due to its quality (taste, odor). Contradictory results were also observed in the study conducted by Ballet et al. (2018) in the Cocody and Yopougon communes in Ivory Coast, where 90% of the surveyed individuals expressed dissatisfaction with the clarity of the distributed drinking water. Safe drinking water must adhere to strict quality standards to ensure it is fit for consumption and poses no health risks.
Color of the water
Drinking water, a vital element for humans, is witnessing the color of its appearance becoming significantly important in terms of both quality and safety. The color of drinking water can provide valuable clues about potential impurities and pollutants, carrying significant implications for public health (WHO 2017). The ideal characteristic of potable water is to be clear, colorless, and transparent, reflecting its purity without any alteration. However, slight variations in color, ranging from pale yellow to light brown, can result from natural factors such as dissolved minerals or algae. Such minor nuances generally do not raise significant safety concerns. Nonetheless, intense and unusual discolorations can indicate a potential problem. For instance, a yellow, brownish, or reddish coloration might signal the presence of heavy metals like iron, copper, or manganese. These metals could originate from the surrounding soil or ageing infrastructure. In certain situations, the coloration may result from the decomposition of organic matter and highly pigmented industrial waste, with the most common being paper and textile waste (EPA 2012). This not only leads to undesirable coloration but also brings about changes in taste and odor.
In a broader context, water color is an organoleptic parameter measured through visual comparison with a set of standard solutions. Levels exceeding 15 units of true color (UTC) can be detected in a glass of water by most individuals.
The obtained results are similar to the findings of Ochoo et al. (2017) in Newfoundland, Canada, where the majority of respondents (>56%) were either completely satisfied or very satisfied with the color of drinking water. However, they contrast with those discovered by Dimitri Miriac et al. (2020) in the Lokossa Commune, in the Southwest of Benin, where 62% of consumers appreciate the drinking water due to its color. Monitoring water color is essential, as it can serve as an indicator of its quality and environmental health.
Presence of debris – fine particles and microbes to the naked eye
Assessment of water quality by debris content – fine particles and microbes visible to the naked eye.
Assessment of water quality by debris content – fine particles and microbes visible to the naked eye.
The results obtained are similar to those found by Ochoo et al. (2017) in Newfoundland, Canada, where the majority of respondents (>56%) expressed complete satisfaction regarding the quality of public water in the absence of fine particles and other debris. However, they contrast with those discovered by Dimitri Miriac et al. (2020) in the Lokossa Commune, southwest Benin, where 81% of the surveyed populations believe that water containing animal and plant debris is inherently dirty and of poor quality. Polluted water is water overloaded with undesirable elements for living beings. Adequate treatments such as filtration, disinfection, and regular monitoring are essential to ensure safe and healthy drinking water.
Drinking water quality
The water consumed by households in the study area is exclusively influenced by the contamination of two physico-chemical parameters (temperature and ammonium) and two bacteriological parameters (total coliforms and total aerobic flora). On the other hand, the 16 other parameters examined, including pH, electrical conductivity, turbidity, total dissolved solids, total hardness, calcium, magnesium, potassium, sodium, bicarbonates, chlorides, sulfates, nitrates, iron, Escherichia coli and Fecal Enterococci comply with the guidelines established by the WHO as well as with national guidelines governing the quality of water intended for human consumption.
Physico-chemical quality of tap water and HPP water
Physico-chemical quality of tap water and HPP water for human consumption
The in situ parameters measured were temperature, hydrogen potential, turbidity, and electrical conductivity (Tables 2 and 3).
Results of physical parameters of water from HPPs
Physical parameters . | Units . | WHO Guidelines . | National Standards . | Observations . | n . | Minimum . | Maximum . | Average . | Standard deviation . |
---|---|---|---|---|---|---|---|---|---|
Temperature | °C | 25 | ≤25 >25 | 0 4 | 29.6 | 30.8 | 30.1 | 0.3 | |
pH | [H3O + ] | 6.5–8.5 | 6.5 ≤ pH ≤ 9 | <6.5 6.5–8.5 >8.5 | 0 4 | 7.0 | 7.7 | 7.4 | 0.2 |
Electrical conductivity | μS/cm | 2,000 | ≤2,500 | ≤2,000 >2,000 | 0 4 | 173.0 | 244.0 | 204.5 | 16.5 |
Turbidity | NTU | ≤5 | ≤5 >5 | 0 4 | 0.8 | 1.0 | 0.90 | 0.10 |
Physical parameters . | Units . | WHO Guidelines . | National Standards . | Observations . | n . | Minimum . | Maximum . | Average . | Standard deviation . |
---|---|---|---|---|---|---|---|---|---|
Temperature | °C | 25 | ≤25 >25 | 0 4 | 29.6 | 30.8 | 30.1 | 0.3 | |
pH | [H3O + ] | 6.5–8.5 | 6.5 ≤ pH ≤ 9 | <6.5 6.5–8.5 >8.5 | 0 4 | 7.0 | 7.7 | 7.4 | 0.2 |
Electrical conductivity | μS/cm | 2,000 | ≤2,500 | ≤2,000 >2,000 | 0 4 | 173.0 | 244.0 | 204.5 | 16.5 |
Turbidity | NTU | ≤5 | ≤5 >5 | 0 4 | 0.8 | 1.0 | 0.90 | 0.10 |
Results of physical parameters of tap water
Physical parameters . | Units . | WHO Guidelines . | National Standards . | Observations . | n . | Minimum . | Maximum . | Average . | Standard deviation . |
---|---|---|---|---|---|---|---|---|---|
Temperature | °C | 25 | ≤25 >25 | 0 3 | 31.8 | 32.1 | 31.93 | 0.09 | |
pH | [H3O + ] | 6.5–8.5 | 6.5 ≤ pH ≤ 9 | <6.5 6.5–8.5 >8.5 | 0 3 | 7.15 | 7.65 | 7.35 | 0.15 |
Electrical conductivity | μS/cm | 2,000 | ≤2,500 | ≤2,000 >2,000 | 0 3 | 542.0 | 606.0 | 582.33 | 20.27 |
Turbidity | NTU | ≤5 | ≤5 >5 | 0 3 | 0.8 | 1.0 | 0.90 | 0.10 |
Physical parameters . | Units . | WHO Guidelines . | National Standards . | Observations . | n . | Minimum . | Maximum . | Average . | Standard deviation . |
---|---|---|---|---|---|---|---|---|---|
Temperature | °C | 25 | ≤25 >25 | 0 3 | 31.8 | 32.1 | 31.93 | 0.09 | |
pH | [H3O + ] | 6.5–8.5 | 6.5 ≤ pH ≤ 9 | <6.5 6.5–8.5 >8.5 | 0 3 | 7.15 | 7.65 | 7.35 | 0.15 |
Electrical conductivity | μS/cm | 2,000 | ≤2,500 | ≤2,000 >2,000 | 0 3 | 542.0 | 606.0 | 582.33 | 20.27 |
Turbidity | NTU | ≤5 | ≤5 >5 | 0 3 | 0.8 | 1.0 | 0.90 | 0.10 |
Case of HPPs
Case of running water taps
Ensuring safe drinking water temperature is vital as it affects microorganism growth and substance dissolution. Warm water can harbor harmful microorganisms, according to WHO (2017)/EPA (2012) which recommend 10–15 °C for human consumption. Our study found 30.1–31.93 °C, exceeding WHO (2017) limit of 25 °C, posing health risks and corrosion potential. Our readings are higher than previous studies: Reyes-Toscano et al. (2020) in Mexico (31–37 °C), Dégbey et al. (2008) in Benin (28.3–29.9 °C), and Sitotaw et al. (2021) in Ethiopia (16.1–24 °C) maintain moderate temperatures to reduce contamination risks.
Chemical characteristics of water samples from taps and HPPs
Ammonium (NH4+) in drinking water arises from natural and human sources (Rusydi et al. 2021). Recent data show an average of 0.7 mg/L, surpassing WHO's limit of 0.5 mg/L. Elevated levels harm ecosystems and lead to groundwater contamination, algae growth, and taste/odor issues. Our measurement is below the EPA's 1.0 mg/L limit but higher than Sitotaw et al. (2021) in Ethiopia (0.2 mg/L). Addressing high ammonium levels requires source identification, improved waste management, fertilizer regulation, and enhanced water treatment for efficient removal (Tables 4 and 5).
Chemical characteristics of water samples from HPPs
Chemical Parameters . | Units . | WHO guidelines . | National standards . | Observations . | n . | Minimum . | Maximum . | Average . | Standart deviation . |
---|---|---|---|---|---|---|---|---|---|
Total dissolved solids | mg/L | ≤ no mention | 84.0 | 123.0 | 99.5 | 9.0 | |||
Total hardness (CaCO3) | mg/L | 500 | ≤ no mention | ≤500 >500 | 4 0 | 32.0 | 58.0 | 46.5 | 6.3 |
Calcium (Ca2+) | mg/L | 100 | ≤200 | ≤100 >100 | 4 0 | 12.6 | 21.0 | 15.8 | 1.8 |
Magnesium (Mg2+) | mg/L | 50 | ≤50 | ≤50 >50 | 4 0 | 0.1 | 4.4 | 1.7 | 0.9 |
Potassium (K+) | mg/L | ≤12 | 1.2 | 2.0 | 1.6 | 0.2 | |||
Sodium (Na+) | mg/L | ≤200 | 13.0 | 23.0 | 17.8 | 2.3 | |||
Bicarbonates (HCO3−) | mg/L | ≤no mention | 39.0 | 70.8 | 56.7 | 7.7 | |||
Chlorides (Cl−) | mg/L | 250 | ≤250 | ≤250 >250 | 4 0 | 12.0 | 20.0 | 16.0 | 1.8 |
Sulfates (SO42−) | mg/L | 500 | ≤250 | ≤500 >500 | 4 0 | 6.0 | 12.0 | 8.5 | 1.3 |
Nitrates (NO3−) | mg/L | 50 | ≤50 | ≤50 >50 | 4 0 | 3.8 | 9.0 | 6.0 | 1.1 |
Iron (Fe) | (mg/L | 0.3 | ≤0.3 | ≤0.3 >0.3 | 4 0 | 0.0 | 1.0 | 0.3 | 0.2 |
Ammonium (NH4+) | (mg/L) | 0.5 | ≤1.5 | ≤0.5 >0.5 | 0 4 | 0.6 | 0.8 | 0.7 | 0.1 |
Chemical Parameters . | Units . | WHO guidelines . | National standards . | Observations . | n . | Minimum . | Maximum . | Average . | Standart deviation . |
---|---|---|---|---|---|---|---|---|---|
Total dissolved solids | mg/L | ≤ no mention | 84.0 | 123.0 | 99.5 | 9.0 | |||
Total hardness (CaCO3) | mg/L | 500 | ≤ no mention | ≤500 >500 | 4 0 | 32.0 | 58.0 | 46.5 | 6.3 |
Calcium (Ca2+) | mg/L | 100 | ≤200 | ≤100 >100 | 4 0 | 12.6 | 21.0 | 15.8 | 1.8 |
Magnesium (Mg2+) | mg/L | 50 | ≤50 | ≤50 >50 | 4 0 | 0.1 | 4.4 | 1.7 | 0.9 |
Potassium (K+) | mg/L | ≤12 | 1.2 | 2.0 | 1.6 | 0.2 | |||
Sodium (Na+) | mg/L | ≤200 | 13.0 | 23.0 | 17.8 | 2.3 | |||
Bicarbonates (HCO3−) | mg/L | ≤no mention | 39.0 | 70.8 | 56.7 | 7.7 | |||
Chlorides (Cl−) | mg/L | 250 | ≤250 | ≤250 >250 | 4 0 | 12.0 | 20.0 | 16.0 | 1.8 |
Sulfates (SO42−) | mg/L | 500 | ≤250 | ≤500 >500 | 4 0 | 6.0 | 12.0 | 8.5 | 1.3 |
Nitrates (NO3−) | mg/L | 50 | ≤50 | ≤50 >50 | 4 0 | 3.8 | 9.0 | 6.0 | 1.1 |
Iron (Fe) | (mg/L | 0.3 | ≤0.3 | ≤0.3 >0.3 | 4 0 | 0.0 | 1.0 | 0.3 | 0.2 |
Ammonium (NH4+) | (mg/L) | 0.5 | ≤1.5 | ≤0.5 >0.5 | 0 4 | 0.6 | 0.8 | 0.7 | 0.1 |
Chemical characteristics of tap water samples
Chemical parameters . | Units . | WHO guidelines . | National standards . | Observations . | n . | Minimum . | Maximum . | Average . | Standart deviation . |
---|---|---|---|---|---|---|---|---|---|
Total dissolved solids | mg/L | ≤no mention | 84.0 | 123.0 | 99.5 | 9.0 | |||
Total hardness (CaCO3) | mg/L | 500 | ≤no mention | ≤500 >500 | 4 0 | 32.0 | 58.0 | 46.5 | 6.3 |
Calcium (Ca2+) | mg/L | 100 | ≤200 | ≤100 >100 | 4 0 | 12.6 | 21.0 | 15.8 | 1.8 |
Magnesium (Mg2+) | mg/L | 50 | ≤50 | ≤50 >50 | 4 0 | 0.1 | 4.4 | 1.7 | 0.9 |
Potassium (K+) | mg/L | ≤12 | 1.2 | 2.0 | 1.6 | 0.2 | |||
Sodium (Na+) | mg/L | ≤200 | 13.0 | 23.0 | 17.8 | 2.3 | |||
Bicarbonates (HCO3−) | mg/L | ≤no mention | 39.0 | 70.8 | 56.7 | 7.7 | |||
Chlorides (Cl−) | mg/L | 250 | ≤250 | ≤250 >250 | 4 0 | 12.0 | 20.0 | 16.0 | 1.8 |
Sulfates (SO42−) | mg/L | 500 | ≤250 | ≤500 >500 | 4 0 | 6.0 | 12.0 | 8.5 | 1.3 |
Nitrates (NO3−) | mg/L | 50 | ≤50 | ≤50 >50 | 4 0 | 3.8 | 9.0 | 6.0 | 1.1 |
Iron (Fe) | mg/L | 0.3 | ≤0.3 | ≤0.3 >0.3 | 4 0 | 0.0 | 1.0 | 0.3 | 0.2 |
Ammonium (NH4+) | mg/L | 0.5 | ≤1.5 | ≤0.5 >0.5 | 0 4 | 0.6 | 0.8 | 0.7 | 0.1 |
Chemical parameters . | Units . | WHO guidelines . | National standards . | Observations . | n . | Minimum . | Maximum . | Average . | Standart deviation . |
---|---|---|---|---|---|---|---|---|---|
Total dissolved solids | mg/L | ≤no mention | 84.0 | 123.0 | 99.5 | 9.0 | |||
Total hardness (CaCO3) | mg/L | 500 | ≤no mention | ≤500 >500 | 4 0 | 32.0 | 58.0 | 46.5 | 6.3 |
Calcium (Ca2+) | mg/L | 100 | ≤200 | ≤100 >100 | 4 0 | 12.6 | 21.0 | 15.8 | 1.8 |
Magnesium (Mg2+) | mg/L | 50 | ≤50 | ≤50 >50 | 4 0 | 0.1 | 4.4 | 1.7 | 0.9 |
Potassium (K+) | mg/L | ≤12 | 1.2 | 2.0 | 1.6 | 0.2 | |||
Sodium (Na+) | mg/L | ≤200 | 13.0 | 23.0 | 17.8 | 2.3 | |||
Bicarbonates (HCO3−) | mg/L | ≤no mention | 39.0 | 70.8 | 56.7 | 7.7 | |||
Chlorides (Cl−) | mg/L | 250 | ≤250 | ≤250 >250 | 4 0 | 12.0 | 20.0 | 16.0 | 1.8 |
Sulfates (SO42−) | mg/L | 500 | ≤250 | ≤500 >500 | 4 0 | 6.0 | 12.0 | 8.5 | 1.3 |
Nitrates (NO3−) | mg/L | 50 | ≤50 | ≤50 >50 | 4 0 | 3.8 | 9.0 | 6.0 | 1.1 |
Iron (Fe) | mg/L | 0.3 | ≤0.3 | ≤0.3 >0.3 | 4 0 | 0.0 | 1.0 | 0.3 | 0.2 |
Ammonium (NH4+) | mg/L | 0.5 | ≤1.5 | ≤0.5 >0.5 | 0 4 | 0.6 | 0.8 | 0.7 | 0.1 |
Bacteriological quality of water from taps and HPPs
According to WHO (WHO 2011) guidelines and Chad's health authority guidelines, drinking water should have no detectable levels of Escherichia coli, total coliforms, fecal enterococci, and total aerobic flora in a 100 mL volume. While Escherichia coli and Fecal Enterococci meet this requirement with 0 MPN/100 mL, the levels of total coliforms and total aerobic flora in the water sample greatly exceed WHO limits, which is concerning (Table 6).
Bacteriological characteristics of tap water samples
Bacteriological parameters . | Units . | WHO Guidelines . | National Standards . | Observations (n = 3) . | ||
---|---|---|---|---|---|---|
Escherichia coli | UFC/100 mL | 00 | 00 | 0 | 0 | 0 |
Total coliforms | UFC/100 mL | 00 | 00 | >100 | >100 | >100 |
Fecal Enterococci | UFC/100 mL | 00 | 00 | 0 | 0 | 0 |
Total aerobic flora | UFC/100 mL | 00 | – | >100 | >100 | >100 |
Bacteriological parameters . | Units . | WHO Guidelines . | National Standards . | Observations (n = 3) . | ||
---|---|---|---|---|---|---|
Escherichia coli | UFC/100 mL | 00 | 00 | 0 | 0 | 0 |
Total coliforms | UFC/100 mL | 00 | 00 | >100 | >100 | >100 |
Fecal Enterococci | UFC/100 mL | 00 | 00 | 0 | 0 | 0 |
Total aerobic flora | UFC/100 mL | 00 | – | >100 | >100 | >100 |
Case of running water taps
Case of HPPs
Total aerobic flora includes microorganisms (bacteria, yeasts, molds) that thrive in oxygen-rich environments (Zabermawi et al. 2022) (Table 7). While it's useful for assessing general contamination, it does not identify specific microorganisms (Behl et al. 2023). A recent analysis of a drinking water sample revealed a high presence of both total coliforms and total aerobic flora (Reitter et al. 2021). While an abundance of total coliforms alone doesn't confirm the presence of pathogenic bacteria, it suggests issues with chlorination, potentially leading to water contamination by harmful bacteria (Le et al. 2023). This contamination is found in both water sources and appears to result from inadequate protection and increased exposure to human, animal, and environmental waste (Dwivedi 2017). This situation could lead to fecal contamination and the emergence of waterborne diseases among residents (Dwivedi 2017). Furthermore, deficiencies in waste and wastewater management infrastructure, shortcomings in drinking water treatment and distribution, limited access to sanitation facilities and toilets, along with low education levels and household incomes, are significant factors contributing to the deterioration of drinking water quality (Licence et al. 2013).
Bacteriological characteristics of water samples from HPPs
Bacteriological parameters . | Units . | WHO guidelines . | National standards . | Observations (n = 4) . | |||
---|---|---|---|---|---|---|---|
Escherichia coli | UFC/100 mL | 00 | 00 | 0 | 0 | 0 | 0 |
Total coliforms | UFC/100 mL | 00 | 00 | >100 | >100 | >100 | >100 |
Fecal Enterococci | UFC/100 mL | 00 | 00 | 0 | 0 | 0 | 0 |
Total aerobic flora | UFC/100 mL | 00 | – | >100 | >100 | >100 | >100 |
Bacteriological parameters . | Units . | WHO guidelines . | National standards . | Observations (n = 4) . | |||
---|---|---|---|---|---|---|---|
Escherichia coli | UFC/100 mL | 00 | 00 | 0 | 0 | 0 | 0 |
Total coliforms | UFC/100 mL | 00 | 00 | >100 | >100 | >100 | >100 |
Fecal Enterococci | UFC/100 mL | 00 | 00 | 0 | 0 | 0 | 0 |
Total aerobic flora | UFC/100 mL | 00 | – | >100 | >100 | >100 | >100 |
The results obtained align with Saïnou et al.'s (2019) findings in Toffo, Benin, particularly in the Sèhouè district. Variations in total coliform concentrations ranged from 105 CFU/100 mL for cistern water to 678 CFU/100 mL for traditional well water 1. Similarities were also observed in Words (2020) work in Kikwit, Democratic Republic of the Congo, with total coliform concentrations ranging from 117 to 450 CFU/100 mL for water from different sources. Osiemo et al.'s (2019) study in Marigat, Kenya, also noted comparable results. Moreover, these findings indicate higher total coliform levels compared to previous studies. Tabor et al. (2011) reported a range of 1.01–100 CFU/100 mL for tap water in Bahir Dar, Ethiopia. Jin-song et al.'s (2020) research in Taladanda Canal, Paradip region, Odisha, India, showed varying total coliform concentrations throughout the year. Yasin et al. (2015) demonstrated 100% total coliform concentration (<100 CFU/100 mL) in all water samples from the water source.
Furthermore, the results differ from Bouba et al.'s (2022) study in Garoua Urbain, Cameroon, where total coliforms accounted for 59% of detected microbes (<100 CFU/100 mL) in sachet water sold. These findings highlight a significant exceedance of WHO guidelines for total coliforms and total aerobic flora in N'Djamena's drinking water. This presents a serious public health concern due to ongoing bacterial contamination. Urgent actions such as improved treatment, enhanced protection, and better waste management are imperative to safeguard water quality and mitigate the transmission of waterborne diseases in the community.
Type of toilets/sanitation facilities, accessibility, and fecal matter disposal methods
To ensure accessibility for all, including individuals with disabilities and reduced mobility, toilets and sanitary facilities must meet accessibility standards. This includes features like wider wheelchair-friendly spaces, handrails, and potential lifting devices. Regular maintenance is crucial for functionality and cleanliness. The survey data reveals that 92.8% of households use traditional toilets as their primary sanitation facility, 2.9% have access to modern flush toilets, and only 4.3% practice open defecation. These latrines are often constructed with various materials, and about 45% have roofing. Modern flush toilets are used by only 2.9% of households due to high material and construction costs, which act as a significant barrier to adoption.
Vacuum sludge collection tanker (a) and disposal of fecal matter into a pit dug around a residential house (b).
Vacuum sludge collection tanker (a) and disposal of fecal matter into a pit dug around a residential house (b).
These findings align with a study by Sy et al. (2011) in disadvantaged neighborhoods of Nouakchott, Mauritania, where 50.7% of households have in-home toilets, and Blackett et al.'s 2014 study in 12 low- and middle-income countries, which found that 98% of households use toilets but only 29% of fecal waste is safely managed. In contrast, a study in central Benin by Dovonou et al. (2022) found that 80% of the population practices open defecation. In Dakar, Senegal, data from the National Agency of Statistics and Demography (ANSD 2018) reveals that 45% of households have access to improved unshared toilets, while 32% use unimproved toilets, often traditional latrines. Toilet facility rates also vary in different regions, with 68.6% using improved toilets in Bamendjou households, Cameroon by Bita et al. (2017), and 35.80% having precarious toilet facilities in Bouaké, Côte d'Ivoire (Tatongueba Soussou 2017). To protect the environment and ensure universal access to safe sanitation, establishing proper waste disposal practices is crucial. Adequate waste management is essential for maintaining cleanliness and creating a healthy, sustainable living environment for all, aligning with the United Nations Sustainable Development Goal (SDG).
Chad faces a critical open defecation problem affecting people of all backgrounds. The Ministry of Water and Sanitation and N'Djamena's municipalities are working to address this issue, but toilets often lack proper standards, leading to groundwater contamination. The rainy season collapses pit latrines, causing widespread pollution. Public toilets deteriorate, giving rise to paid private ones, mainly in markets and hospitals. Urgent policies are needed to provide sanitation assistance to disadvantaged and middle-income households, safeguarding groundwater and public health.
Wastewater evacuation method
Efficient wastewater management is vital for safeguarding public health and the urban environment (Oyebode 2018). It includes collecting, transporting, and treating wastewater to reduce health and environmental risks (Khan et al. 2021). Surprisingly, a survey reveals that nearly 95% of households, regardless of factors like education, religion, or lifestyle, dispose of wastewater in the environment or streets. Only 5% use septic tanks. This untreated wastewater often ends up in rivers or evaporates, causing pollution and health hazards (Mekonnen & Amsalu 2018). Some health centers even release untreated wastewater directly, worsening living conditions and environmental issues (Tariq & Mushtaq 2023).
Stagnant wastewater surrounds a small market in the ninth arrondissement.
Garbage disposal method
N'Djamena Nadif (a) dump truck, pushcart (b), and motorcycle (c) for household waste transportation.
N'Djamena Nadif (a) dump truck, pushcart (b), and motorcycle (c) for household waste transportation.
In certain neighborhoods, the absence of public waste disposal facilities leads to improper household waste disposal. People often dump garbage in random locations, including depressions or old quarries. This even involves using household waste as landfill material, leading to groundwater pollution. Managing biomedical waste is complex, and there are no available statistics. Previously, health centers and hospitals had incinerators, but the situation has changed. Only 10.4% of households in the third and ninth districts are satisfied with sanitation services. These findings are consistent with Sy et al.'s (2011) study in Nouakchott, Mauritania, where 17.1% of households have access to household waste collection. Similarly, Mbiadjeu Lawou et al.'s (2021) study across Cameroonian cities revealed that 57% of households dispose of their waste in open dumps. These results differ significantly from prior studies. In Brazzaville, Republic of Congo by Mangoumbou et al. (2023), 61.7% of households have trash bins, while 38.3% do not. Conversely, in Zangnanado, Benin by Dovonou et al. (2022), 100% of the population disposes of their waste in the environment. Furthermore, in Porto-Novo, Southern Benin by Hoteyi et al. (2014), fewer than a quarter of households are subscribed to pre-collection waste services, with 42.73% burying waste and 30.91% burning it in the open air.
Municipalities and local sanitation committees are responsible for launching awareness campaigns to encourage households to use public waste disposal sites and hire private waste collection services, with the aim of enhancing the immediate environment and overall well-being.
Hygiene facilities and practices
Maintaining proper hygiene across various settings such as workplaces, homes, schools, healthcare facilities, and public spaces is vital for disease prevention and overall well-being (WHO 2020). A survey revealed that 45% of households have handwashing facilities, but 55% lack consistent access. Among these facilities, 69% are clean, 27% are in poor condition, and 4% are not visible. Some households bring their own hygiene containers. Communal handwashing facilities often lack maintenance, with soap frequently absent or stolen. Curtis and Cairncross propose that promoting soap as a desirable household item may be more effective than hygiene campaigns. Surprisingly, 95.5% of households prioritize handwashing with soap and clean water, irrespective of education, religion, or lifestyle. Globally, one in four people lacks access to soap and water for handwashing, with only 26% practicing handwashing after potential fecal contact by Wolf et al.(2019). Rates are even lower in sub-Saharan Africa (14%) and Southeast Asia (17%). Poor hygiene can result in waterborne diseases, particularly in children aged 0–5 years, leading to stunted growth and delayed development (Al-Ghamdi et al. 2009; Humphrey 2009). These findings contrast with studies in other regions, such as Benin (70.41% lacking handwashing after defecation), Senegal (14.3% limited hand hygiene to water), and Vietnam (poor hygiene due to lack of knowledge and ingrained habits) (Martin et al. 2019; Diop et al. 2021). The WHO recommends handwashing with soap and water, particularly when hands are visibly soiled (WHO 2017).
CONCLUSION
The study conducted in the third and ninth districts of N'Djamena has shed light on major challenges related to water supply, sanitation, and hygiene. Despite the presence of institutional actors, deficiencies in financial, material, and technical resources were observed. Water quality analyses from two sources revealed contamination by temperature, ammonium, total coliforms, and total aerobic flora, rendering it unsuitable for consumption according to WHO guidelines. The inadequacy of sanitation and hygiene services is evident. While overall access to water is satisfactory, sanitation facilities do not meet recommended standards. Traditional communal latrines are widely used, underscoring the absence of a wastewater and fecal matter treatment system. In conclusion, hygiene promotion is crucial to prevent household contamination by fecal matter. The importance of accessible handwashing facilities, soap, and proper treatment to improve water quality is emphasized. Additionally, the collection and safe disposal of household waste pose a major challenge in Ndjamena, particularly in the study area.
RECOMMENDATIONS
To effectively ensure the population's health preservation in these two districts, the study recommends providing interest-free microloans to households to help them build modern toilets, thus ensuring safe waste disposal. It is also essential to guarantee access to safe drinking water and promote good hygiene practices. This includes subsidizing handwashing soaps, providing hygiene education within the community, and continuing awareness campaigns to encourage behavioral change. Finally, rational waste management and the promotion of a circular economy are crucial elements for ensuring sustainable development in the study area.
ACKNOWLEDGEMENTS
The authors express their profound gratitude to the World Bank, through the Regional Center for Energy and Environmental Sustainability, for their financial support of this study. They also extend their warm appreciation to the ten investigators from the third and ninth districts of the city of N'Djamena, as well as the local authorities for their unwavering support throughout the survey.
DATA AVAILABILITY STATEMENT
All relevant data are included in the paper or its Supplementary Information.
CONFLICT OF INTEREST
The authors declare there is no conflict.