Strategies for Household Water Supply Improvement with Rainwater Harvesting

There are significant household water supply challenges including quantity sufficiency and quality, which have economic and social implications. The challenges have remained despite the efforts of government establishing centralized or groundwater systems, and/or having individual crude systems. A Tanzanian rural household case study was considered by assessing the performance of a currently relied surface runoff collecting pond system for domestic purposes. A daily water balance model was applied with performance parameters, no water days (NWD) and rainwater usage (RUR). Rooftop runoff harvesting system was proposed as a water supply source in addition to the current one. Under such dual supply conditions, users can meet the drinking and non-drinking demand even in dry seasons at a minimum of 2 and 20 L/person/d, respectively. For rainwater harvesting adoption (considering selected regions), it was further established that amount and variation in rainfall impacts on quantity available for meeting demand. Increased catchment implies increased harvestable quantity, and with same storage higher reduction of number of NWD although with slight decrease of RUR. Also, increased storage is required for achieving higher RUR in case the same demand is maintained. But same storage can be maintained for increased demand relative to catchment size. However, rainwater catchment increase has greater impact on meeting a specified demand under given condition of rainfall quantity and variation. The RWH technology strategies presented in this study are replicable in other developing countries under site specific conditions.

Collaborative Efforts and Strategies for Cholera Outbreak Control in Garissa County, Kenya: Implementation of Water Quality Monitoring Interventions

A multi-faceted Case Area Targeted Intervention (CATI) approach emphasizing the integration of Water, Sanitation and Hygiene (WASH) interventions and Oral Cholera Vaccine (OCV) campaign was employed to respond to the outbreak of cholera in Garissa County. Drinking water sources in areas heavily impacted by cholera were systematically mapped and tested for microbiological quality. The quality assessment was carried out in April 2023 during an ongoing cholera outbreak in the county. A total of 109 samples were collected and tested for thermotolerant coliforms and other in situ parameters. The finding revealed that more than 87% of the samples did not meet the World Health Organization (WHO) standard for thermotolerant coliforms;and 30% had turbidity values above the recommended threshold values. None of the 109 samples had any traceable residual chlorine. Following these findings, the county government implemented the targeted interventions which resulted in a positive impact in the fight against cholera. The WHO supported key interventions which included capacity building in water quality monitoring and prepositioning of critical WASH commodities to the cholera affected areas.

Climate Influenced Challenges of Accessibility to Water by Households Downstream of the Upper Benue River Basin-Nigeria

The study examined climate influenced challenges of accessibility to water by households downstream of the Upper Benue River Basin, Nigeria. Literatures related to the topic being investigated were reviewed. The study adopted a descriptive survey design. The population of the study consisted of communities in Adamawa, Gombe, Bauchi and Taraba states. Eight different communities, two in each local government were sampled for the study. Simple random and purposive samplings were used for the study. A total of 351 respondents were selected for the study using Krejcie and Morgan sample size determination. Data analysis was done using frequency tables percentages and mean statistics. The findings of the study showed that climate variability has great impact on water stress and threats to households’ downstream in Upper Benue River basin represented with a mean 3.85 (decrease in the quality and quantity of surface water) as well as 3.43 (drying up of rivers and lakes). The study also revealed that water stress induced by climate variability has a significant effect on household livelihoods represented by 87% of the respondents in the study area. It was also revealed that that households downstream the basin are vulnerable to climate change and households in the study area have development strategies to contend with water stress so as to better their livelihood among which is surface water harvesting (2.78), reducing the number of times dishes are washed (2.96), reducing the quantity of water used for bathing (3.0) among others. The study recommended that stakeholders and the government should make proactive efforts to ensuring that alternative water sources are established in the study area to reduce water stress among the rural populace.

Using Double-Bounded Dichotomous-Choice to Estimate Households’ Willingness to Pay for Improved Water Quality in Bac Ninh Province of Vietnam

This study used double-bounded dichotomous-choice to estimate and analyze the factors affecting households’ willingness to pay (WTP) for water quality improvement. This study notes that households with higher income, living near a polluted water source, using tap water instead of natural water, who are handicraft producers, and who have more members, are willing to pay more. However, households who rarely hear about environmental pollution issues and who are offered a higher bid are more likely to refuse to pay. Solutions to improve water quality are suggested such as to raise people’s awareness through communication channels and social organizations;to increase income associated with environmental protection policies;to construct wastewater treatment plants;to encourage the relocation of production establishments to industrial parks and industrial complexes;to put regulations on collection, payment and sanctions in case of not declaring and paying fees into village conventions;to promulgate circulars, and bylaws to concretize and simplify regulations and policies of the Government and the Ministry of Natural Resources and Environment.

Quality of Water Adjusted Sources and Storage in the Households of the Sanitized Villages in Area of National Program of Sanitized Schools and Villages at Tshopo Province in Republic Democratic of Congo

Introduction: The present research paper aims at assessing the bacteriological water quality in households and at provisioning points, and so factors of water deterioration. Method: a transverse study has been conducted during the period starting from 11 up to 28 October 2018 within 6 Health Zones (HZ) in Tshopo Province integrated in National Program of Schools and Sanitized Villages (NPSSV). Water samples have been collected within 300 reserves of households and 30 water provisioning and analysed points in order to find out water contamination factors. The frequencies and raw OR have been estimated at (p < 0.05) valued significative. Results: fecal coliforms (80% CI95: 75% - 85%) and total (97% CI95: 95% - 99%) were significantly present in water reserves and the presence of Escherichia coli were at about 27% (IC95 22% - 32%). These proportions were correspondingly at 63%, 90% and 10% at water provisioning. The fecal coliforms were the highest in water reserves of sanitized villages (p < 0.05) and Escherichia coli were at about three times higher in traditional sources (17% vs 6%). The duration of water conservation was around 48 hours and more (OR = 4.41;IC95: 1.92 - 10.11), water classification of sanitized risk “intermedium” and the recipients of conservation with bottleneck were associated with the presence of E.coli in water (p < 0.05). Conclusion: water from provisioning sources and household reserves are severely polluted and water quality is not good at consumption point and at provisioning point. The reinforcement of safety measures at water points, reduction of conservation length and hygienic water cleaning of storage water recipients are necessary to assure quality of water.

Improving Self-Supply of Urban Water and Sanitation Projects through Microfinancing in Nigeria

Most water and sanitation projects in poor neighbourhood of urban Nigeria are executed through self-supply option. This is defined as an incremental improvement of WASH products e.g. water and sanitation structures by a household or small group of households which are financed by their own effort and investment. It is indeed a concept which complements conventional water supply and sanitation funded by government. The aim of this paper is, therefore, to investigate the extent of the use of innovative financing especially group saving approach to improve water and sanitation projects in Awka town, Nigeria. Towards achieving the aim, data were collected through questionnaires which were designed and administered on the respondents between January and April, 2016 and from other secondary sources. Data were analyzed using Principal Component Analysis and Component scores to establish the extent of the use of this option in the 9 component quarters of the town. Result shows that some quarters have perfected using the self-supply option while in others, it is yet to be widely accepted. It is finally recommended among others that the urban water policy as well as urban water safety plan should be revised to include the option as a way of improving domestic water supply and sanitation in the town.

家用活性炭滤芯与反渗透膜滤芯对饮用水中全氟化合物的去除性能试验

饮用水中普遍检出全氟化合物(PFASs)。该研究以4种典型的PFASs,即全氟丁基羧酸(PFBA)、全氟己基磺酸(PFHxS)、全氟辛基羧酸(PFOA)及全氟辛基磺酸(PFOS)为目标物质,以活性炭滤芯及反渗透(RO)膜滤芯两种常用家庭净水部件为研究对象,测试两种净水材料对PFASs自来水加标水样的去除性能及过滤前后相关水质参数。结果表明,对于活性炭滤芯,PFHxS、PFOA、PFOS在7倍额定总净水量内去除率为72%~86%,PFBA去除率相对较低,且通水量超过2倍额定总净水量后,去除率呈明显下降趋势;PFASs的去除率与高锰酸盐指数、溶解性总固体、无机阴离子等水质参数不相关;对于RO膜滤芯,PFASs的去除率可达90%~100%,PFBA去除率在通水后期呈现缓慢下降趋势;PFHxS、PFOA及PFOS的去除率与溶解性总固体、氯化物、硫酸盐等无机阴离子浓度呈较好的相关性。因此,家用活性炭滤芯、RO膜滤芯对饮用水中的PFASs具有良好的去除效果。研究可为家庭净水装置去除PFASs提供使用参考。

中国居民家庭生活用水十点规律与认识

居民家庭生活用水刚性强、标准高,是水资源消费最主要的终端单元,也是近年来我国经济社会用水需求增长最快的用户,其发展规律和未来趋势深刻影响对总体用水格局的分析。通过系统监测、试验、调查和模拟研究,阐释了家庭生活用水行为占比、不同人群生活用水差异、节水器具、节水宣传、水价等对生活用水的影响规律,对比分析了国外和我国生活用水变化规律,提出家庭生活用水增长规律,构建了基于人口特征的需水变化曲线,预测了未来我国居民生活用水变化趋势,以期为我国生活节水管理和总体用水发展趋势研判提供参考。

The Dynamics of Domestic Water Vending in Enugu North L.G.A of Enugu State, Nigeria

The present investigation provides a case study of water vending in Enugu North Local Government Area, Enugu State of South Eastern Nigeria. Questionnaire copies were randomly distributed in the study area to 200 households. Data obtained from the field were analyzed using descriptive statistics and chi-square test. The analysis revealed that almost all the residents of Enugu North L.G.A. obtain their water from independent water vending systems which are operated by the private sector. Tanker truck, distributing and small retail water vendors all operate in the study area. There are an estimated number of 250 tanker truck drivers serving Enugu North L.G.A. Approximately 35 tanker trucks serve Hill- top/Udi siding ward, while there are a total of 52 retail vendors in Onuasata ward. Majority of the respondents are low income earners who spend within the ranges of NGN500 ($3.33) and NGN1500 ($10) a month on water on the average. 50.0 percent of these respondents opined that vended water was expensive. Of the respondents, 49.4 percent consumed 91 - 100 litres per capita per day, which is less than the 120 litres per capita per day recommended by the Federal Re- public of Nigeria’s National water supply and sanitation policy document of 2000. This deficit can be attributed to the cost of vended water. From the chi-square test, there is significant difference in the unit cost of water sold by vendors in the various wards in Enugu North L.G.A. In the absence of regular water provision through pipe-connections from the public utility, water vending should be supported but regulated. Meeting the water and sanitation target and optimizing water resources for the Millennium Development Goals (MDGs) by 2015 will require a dramatic scaling up of joint efforts by the state government and the people in ensuring that vendors provide safe water at a low cost.

Survey on Storage of Water for Domestic Use in Underground Reinforced Concrete Tanks: The Case of Brazzaville (Republic of Congo)

The problem of water supply from the public distribution network still poses very serious problems in many cities in developing countries. Intermittent water supply pushes some households to build underground reinforced concrete tanks for water storage to cope with unwanted water breaks. This study that relies on the results of a survey of households in some areas of the city of Brazzaville (Republic of Congo) aims to verify the importance that users attach to the quality of the works constructed. Indeed, the reliability of the tanks resulting in their impermeability to the external environment has a direct impact on the quality of stored water and therefore the use that is made of water daily. Five areas were selected because of their soil moisture. By 256 tanks identified, 143 are made of reinforced concrete and 113 in masonry. The coating materials used to seal the walls are preferably the earthenware tiles (64% of tanks), then the Sika cement (31%). Food painting (5%) is only rarely used. However, 66% of households are not assured of the potability of the water stored. A significant number of households (46%) think that the stored water could be contaminated with noxious substances seeping from the outside through the walls of the tanks. The issue of sealing of underground water tanks, especially in areas where the water table is shallow, seems concerned users.

Dihalogenated nitrophenols in drinking water:Prevalence,resistance to household treatment,and cardiotoxic impact on zebrafish embryo

Dihalogenated nitrophenols(2,6-DHNPs),an emerging group of aromatic disinfection byproducts(DBPs)detected in drinking water,have limited available information regarding their persistence and toxicological risks.The present study found that 2,6-DHNPs are resistant to major drinking water treatment processes(sedimentation and filtration)and households methods(boiling,filtration,microwave irradiation,and ultrasonic cleaning).To further assess their health risks,we conducted a series of toxicology studies using zebrafish embryos as the model organism.Our findings reveal that these emerging 2,6-DHNPs showed lethal toxicity 248 times greater than that of the regulated DBP,dichloroacetic acid.Specifically,at sublethal concentrations,exposure to 2,6-DHNPs generated reactive oxygen species(ROS),caused apoptosis,inhibited cardiac looping,and induced cardiac failure in zebrafish.Remarkably,the use of a ROS scavenger,N-acetyl-l-cysteine,considerably mitigated these adverse effects,emphasizing the essential role of ROS in 2,6-DHNP-induced cardiotoxicity.Our findings highlight the cardiotoxic potential of 2,6-DHNPs in drinking water even at low concentrations of 19μg/L and the beneficial effect of N-acetyl-l-cysteine in alleviating the 2,6-DHNP-induced cardiotoxicity.This study underscores the urgent need for increased scrutiny of these emerging compounds in public health discussions.

Radioactive Contaminants in U.S. Drinking Water and Water Quality Disparities

Radioactive contaminants, such as radium, radon, and uranium isotopes are naturally present in drinking water, and gas and oil extraction like hydraulic fracturing can exasperate radionuclide leakage into groundwater. The concentration of radionuclide in drinking water is dependent upon the water source and the underlying lithology within the aquifers. In United States, the Environmental Protection Agency regulates the level of radioactivity in drinking water via the gross alpha test, which is conducted to measure the emitted alpha particles as a result of the radioactive elements’ natural decay. Radionuclides, such as radium and uranium, are known to cause bone cancer and other forms of cancer. Communities with crippling water purification infrastructure may be at a higher risk of being exposed to radionuclides, and this is a significant environmental justice concern. The radionuclide concentrations for the metropolitan or most populated city in each state in the United States and its territories (Puerto Rico, US Virgin Islands and Guam) were analyzed and correlated to the annual household income, to determine any disparities that maybe present. Lower income communities had elevated levels of radionuclides when compared to higher income communities which had lower frequency in elevated radionuclide contaminants.

Vietnam’s Future Water Usage Model: A Controlled Living Experiment

The purpose of this study was to explore the water usage profile of future Vietnamese households by carrying out a controlled living experiment with Vietnamese high-income households. By studying showering time, flow rate and toilet-use frequency of these households, the study revealed the water usage believed to be representative of future households in light of continued urbanization. This study also determined that the average time of showering was 9.7 minutes per person per day with an average flow rate of 12 L/minute for the existing shower head and 6.6 L/minute for the water-saving shower head. Toilet usage frequency was 5.25 times per person per day, and there was no difference with the results for an average (middle-income) household.

Breeding Site Characteristics of Mosquito in Ouagadougou, Burkina Faso

Urban areas deal with the emergence or resurgence of transmissible and non-transmissible diseases, linked in particular to urban lifestyle and sanitation issues. Human practices create or maintain conditions that favour mosquitoes’ breeding. This study investigates mosquito breeding sites characteristics in Ouagadougou, from September to November 2020. Mosquito larvae were sampled across three districts in the city, chosen based on socio-demographic and urbanization levels. The larval collection from natural breeding sites using the ladle technique and larvae transferred to can. For artificial sites, the larvae were transferred directly into can Larvae were collected from 83 breeding sites, predominantly artificial: 39% in plastic containers, 23% in clay containers, and 13% in metal, while natural sites like puddles accounted for only 25%. A total of 8352 mosquitoes were identified as six species: Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, Anopheles gambiae s.l., Anopheles funestus, and Mansonia africana. Ae. aegypti was the most prevalent, found across all breeding site types, whereas Culex quinquefasciatus and Anopheles gambiae were mainly in natural sites. Physico-chemical analysis of the breeding sites revealed that conductivity and turbidity were consistent across breeding sites. The highest median pH values were observed in ceramic and metal containers. Water temperature showed minimal variation. The presence of Anopheles gambiae and Culex quinquefasciatus correlated with higher water temperature, turbidity, and conductivity. Anopheles funestus preferred high pH environments. Conversely, Aedes aegypti, Aedes albopictus, and Mansonia africana were less influenced by these parameters. The findings underscore the need for community involvement in water and waste management to control mosquito populations, especially targeting the Aedes aegypti species. Raising awareness among locals about proper water storage and disposal practices is crucial for effective vector control.

Diversifying Clean Water: An Examination of Drinking Water Quality and Social Disparities in Michigan

Water is one of the most essential resources required to sustain life. However, it could be detrimental to the health of those without access to water that is properly treated. Although the Safe Drinking Water Act of 1974 set regulations to protect citizens from naturally occurring and man-made contaminants, some people are still without clean and safe water, which is speculated to be because of their race. This research examines the disproportionality of available clean water provided by government sources in Michigan and its correlation with race and household income. In the study, it has been found that one of the leading causes of water contamination is industrial activity, with the automobile industry being responsible for approximately 300 million tons of lead contamination in water, and that the manufacturing company’s locations mostly centered in minority and low-income areas. Lower income cities, such as Hamtramck and Benton Harbor, have an average of 14.8 drinking water standard violations with the highest being 99 total violations, while higher income cities, like Novi and Bloomfield hills, have an average of 4 violations. Cities, like Flint and Detroit, which have a higher minority population, are 10 times more likely to have a water standard violation, and the minority population is proportionally related to the possibility of industrial manufacturing being located in those areas. These communities also face a higher risk of birth defects, developmental issues in children, and organ failure in adults, due to continuous exposure to water contaminants. Race as a direct causation could not be proven, but there are links to direct correlation through historical redlining and housing trends.

Puerto Rico’s Water Supply: An Investigation of the Levels of Trihalomethanes and Other Contaminants

The US Commonwealth of Puerto Rico is comprised of 143 islands, atolls, cays, and islets. Of the 143 localities, only 3 islands are inhabited: The mainland (often referenced as Puerto Rico), Culebra, and Vieques. To properly analyze the water supply quality, the mainland will be the focal point for examining environmental and social injustices. Puerto Rico is a racially diverse but ethnically homogenous territory, with most of the commonwealth living below the poverty level. Access to clean water sources is always tenuous in Puerto Rico. Over 70 percent of the island is served by water, violating US health standards. However, the recent hurricanes made the situation even more detrimental. According to data reported between January 2015 and March 2018 by the Consumer Confidence Report (CCR), 97 percent of the population of Puerto Rico utilizes a common drinking water system with one or more recent violations of the Safe Drinking Water Act for its testing requirements for lead and copper levels. The amounts found were far higher than any US state, meaning that virtually everyone on the island gets water from systems that violated testing or reporting requirements. In this study, we have collected and analyzed the levels of trihalomethanes (THMs), haloacetic acids (HAAs), copper, lead, and total organic compounds (TOCs) in drinking water providing systems in Puerto Rico and compared them with the recommended levels of contaminants provided by the US Environmental Protection Agency (EPA) guidelines. Many of these reported contaminants can have serious and detrimental health effects after prolonged exposure to higher concentrations of the contaminants found in the drinking water sources of Puerto Rico.

2019年天津市农村家庭环境卫生行为影响因素研究

目的调查天津市涉农区农村家庭的卫生行为状况,分析其影响因素。方法于2019年对天津市的三个典型涉农区采用多阶段随机抽样的方法,抽取60个样本村和300户农村家庭后进行横断面调查,主要内容包括农村环境卫生基本情况、家庭基本情况和家庭卫生行为。采用多水平Logistic回归模型分析农村环境卫生条件、人口经济学状况对家庭卫生行为指标的影响。结果村内是否组织改厕对农户家庭是否使用卫生厕所的影响有显著性(P<0.05);提供间歇性供水的村中,喝包装水的家庭所占比例较连续性供水的村更低(P<0.05);农村家庭是否使用卫生厕所以及农村家庭的饮水习惯在行政村水平存在聚集性(P<0.05)。结论村内有组织的改厕可以促进村民使用卫生厕所;间歇式供水可能会引起居民家庭饮水方式的改变,与农民家庭卫生行为相关的环境卫生条件的保障需要引起足够关注;对具有村-户两级嵌套结构的数据分析时,更适合采用层次结构模型。

不同乡村地域类型农户生计资本和生计策略特征及影响因素——以于桥水库流域为例

农户生计方式不仅决定了农户的收入,还对区域环境产生了深刻的影响。不同乡村地域类型是影响农户生计资本和生计策略的重要因素。本研究通过参与式农村评估和问卷调查获取于桥水库流域512份农户生计的一手数据,构建了农户生计资本评价指标体系,依据收入结构划分农户生计策略,分析不同乡村地域类型的农户生计资本和生计策略特征,并利用多元回归方程解析生计资本对生计策略的影响。结果表明:流域内农户生计非农化成为普遍现象,纯非农型和非主农辅型生计策略占比分别为29.5%和42.6%。不同生计策略农户的生计资本存在显著差异:纯非农和非主农辅农户的总生计资本、人力资本、社会资本和金融资本显著高于纯农业和农主非辅农户,纯农业和农主非辅农户的自然资本显著高于纯非农型农户。不同乡村地域类型农户的生计资本水平和生计策略选择具有明显差异。经济作物区农户的总生计资本、自然资本显著高于其他地区,传统粮产区的金融资本最低。水库周边区生计策略主要为纯非农型,山地林木区和城镇周边区主要是非主农辅型,传统粮产区和经济作物区主要是纯非农型和非主农辅型,文化旅游区主要是非主农辅型和农主非辅型。人均耕地面积、人均林地面积、耕地破碎化程度、土壤肥力、劳动力占比、家庭人口平均年龄、交通工具和家庭人均收入等指标对农户生计策略选择具有显著影响。不同乡村地域类型生计资本和生计策略差异主要与地理区位、自然资源、社会资源和政策相关。最后,提出基于乡村地域特征的农户生计的针对性优化策略,为促进农户生计可持续发展提供参考。

家用净水器精准净化性能评价技术研究

我国幅员辽阔,受区域环境季节等因素影响,各地区水质差异明显,近年来,研究不断发现水体中内分泌干扰物、抗生素等新型污染物,水污染形势愈发严峻。现有的饮用水处理系统对这些新型污染物的控制能力有限,家用净水器作为饮用水的最末端处理设施,近年来在居民家中占有率逐年上升。因产品材料结构组成多样、生产工艺复杂,潜在有害物质的种类和迁移不明,随着水污染时间不断增多,现有的检测技术无法精确量化产品品质,质量监管受到约束,因此对市面所售净水器精准净化能力提出了要求。本文以市售净水器为研究对象,建立了饮用水处理装置精准净化检测方法,对净水器中具体物质(如铅、砷等)的去除或净化能力进行评价,建立家用净水器对农药去除率测试方法、对抗生素去除率测试方法,通过对去除效果进行分级,指导消费者进行选购以及制造商技术升级。

基于居民舒适度的差异化家庭器具水资源配置

居民用水舒适度差异化使得传统“一刀切”的水分配方案不仅无法满足家庭差异化用水需求,还导致水资源浪费。针对上述问题,文章提出基于居民舒适度的差异化家庭器具用水调度模型与算法。揭示居民家庭器具用水习惯与用水舒适度的关系,并根据居民用水习惯对家庭器具进行分类,同时建立不同类型器具的节水率区间,根据家庭器具二维动态优先级划分不同类型居民的用水舒适度,联合不同类型居民舒适度和不同种类器具节水率构建基于居民舒适度的用水配置数学模型。为高效求解数学模型,提出了一种改进的原子搜索算法(improved atomic search algorithm,IASO),仿真结果显示了在不同类型居民用水舒适度下家庭器具的用水量。对居民器具用水进行细化研究,为建立节水舒适型家庭提供参考。