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Dans la perspective d’ameliorer l’acces aux services de base en eau potable, hygiene et assainissement (EHA), le Mali a fait de ce secteur une priorite depuis 2006. Cette etude avait pour objectif de mener une analyse critique du diagnostic de l’acces aux services de base EHA et l’impact des deplaces internes de la crise politique et securitaire de 2012 sur ces services dans la commune de Zan Coulibaly afin de proposer des strategies locales perennes. Les donnees ont ete collectees a travers une fiche de questionnaire semi-structuree, des observations directes sur le terrain et la consultation des documents administratifs. L’enquete a revele que les forages (40%) et les puits traditionnels (28%) etaient les principales sources d’approvisionnement en eau. La collecte de l’eau est une activite exclusivement feminine. Pour traiter l’eau de boisson a domicile, la filtration sur linge etait la technique la plus utilisee (71%). Malgre un contexte pandemique a COVID-19, seulement 24 % des personnes interrogees lavaient les mains au sortir des toilettes et 22% avant de manger. Aussi, 16% des enquetes pratiquaient toujours la defecation a l’air libre. De 2016 a 2020, on note une persistance des maladies diarrheiques et une reapparition des maladies dues aux vers intestinaux. Par ailleurs une eradication du trachome et du cholera a ete observee. Neanmoins, les resultats relatifs au site des deplaces internes de la crise, sont alarmantes. Ces donnees constitueraient une base pour mieux orienter les politiques et les actions futures relatives aux services EHA dans la commune de Zan Coulibaly. To improve the access to the basic water, sanitation and hygiene (WASH) services, Mali has made this sector a priority since 2006. This study aimed to conduct a critical analysis of the diagnosis of access to WASH basic services and the impact of internally displaced people from the political and security crisis of 2012 on these services in the rural commune of Zan Coulibaly in order to propose sustainable local strategies. The data were collected throughout a semi-structured questionnaire form, direct observations on the sites in the nine villages, and the consultation of executive documents. The survey revealed that the drilling (40%) and the traditional wells (28%) were the main sources of water supply. The water collection is an exclusively female activity. To treat drinking water at home, the filtration was the most commonly used technique (71%). Despite a pandemic context of COVID-19, only 24% of respondents washed their hands after leaving the toilet and 22% before eating. Also, 16% of respondents have always defecated in the free air. From 2016 to 2020, we note the persistence of diarrheal diseases and the reappearance of intestinal worm diseases. Otherwise, the trachoma and the cholera were eradicated. Nevertheless, the results relating to the internally displaced people from the crisis are alarming. These data could provide a basis for better guiding the future policies and actions in the provision of WASH services in the rural commune of Zan Coulibaly.

Settlement schemes are aimed at settling landless people and those displaced by disasters to support socio-economic and environmental development of a country. Eastern Mau Forest Reserve is an important water catchment that has settlement schemes established, which has led to encroachments and degradation of the catchment. This paper, therefore, assesses the implications of human settlements on Eastern Mau water catchment by examining the trends in land use/cover change and river flows for four decades. Primary data was collected from key informant interviews based on purposive sampling whereas secondary data was derived from Landsat satellite images over a 10-year period and analysed using Maximum Likelihood Function from ArcGIS. Data on river flows from River Njoro was obtained from Water Resources Authority Office in Nakuru. Rainfall and temperature data were obtained from Kenya Meteorological Station in Nakuru. Time series analysis is used to understand the trend in river flows over time while Pearson correlation is used to determine relationship between farmlands and river flows. The results indicate a sharp decline in forest cover by 42.7% and an increase in farmlands by 41%. Dense vegetation and farmlands have an inverse relationship as an increase in farmlands lead to a decrease in forest cover. People have settled beyond the established settlement schemes boundaries leading to encroachment and drying up of some rivers. There is also an increase in rainfall and river flows over the years, with monthly river flows increasing in peak flows and declining during low seasons. There is a positive correlation between farmlands and river flows between 1989 and 2020. There is need for regeneration of encroached areas and defining boundary of Eastern Mau to allow initiatives and interventions that help with sustainable management of the catchment area.

Most residents in developing countries suffer severe water shortage and often resort to self-supply. Unfortunately, some self-supply water sources contain disease-causing biological and chemical contaminants and require point-of-use (POU) treatment. However, recontamination and persistence of chemical contaminants occur, which defeats the aim of POU. This study aims to develop an affordable low-technology system that effectively treats whole-house water sourced from borehole and rain without recontamination. Raw borehole water (RBW) was treated with KAl(SO4)2·12H2O (8.10 mg/L), Ca(OH)2 (68.21 mg/L) and NaOCl (1.875 mg/L) in two separate tanks and thereafter filtered through 5-micron and 0.5-micron carbon filters, and a reverse osmosis system. The results showed that heterotrophic plate count (2,700 CFU/mL) and total coliform (378.00±21.25 MPN/100 mL) in RBW were reduced to zero, and total hardness was reduced by >83% after treatment and there was no recontamination. Chromium (0.05±0.002 mg/L), Cu (0.04±0.001 mg/L), Pb (0.09±0.001 mg/L), Fe (0.26±0.005 mg/L) and Mn (0.2±0.001 mg/L) in the RBW were reduced below detectable limits after treatment. The annual per capita cost of water treatment was estimated at N 4,744.44 ($9.32) at per capita consumption of 100 L/day. Our technology shows exceptional promise in providing affordable and safe water to the entire household throughout the year.

Purpose. Reconstruction of water supply systems to meet the increased water needs of consumers is a complex, time-consuming and expensive task. Reconstruction options include expanding existing water intakes or building new ones anywhere in the existing water supply network. The variety of options is accompanied by changes in water consumption in the sections of the networks and, importantly, in the flow distribution. The introduction of additional sources into the existing water supply systems requires a detailed study of the factors affecting the technical characteristics of the systems and responsible for the economic component of the project. Methodology. The influence of the determining factors on the total head losses in the water distribution network during the reconstruction of the water supply system is analyzed. An algorithm for finding the optimal network points for connecting an additional power source is proposed, which includes determining the optimal flow distribution and the corresponding technical changes for each selected option; total capacity of pumping stations and heads; analysis of the complete set of the water supply system of the accepted options; an economic analysis of the construction investment and operating costs that will accompany the operation of the water supply system design options. Findings. The choice of the optimal connection points for additional power sources depends on the amount of water flow in the network sections and the flow distribution. It is shown that the nodes of the end sections of the network most correspond to the conditions for searching for optimal points and can be fed from different directions, depending on the amount of additional flow. With an additional water flow rate no more than two nodal flow rates, the total head losses in the network sections are minimal. When an additional flow rate of more than two nodal flows enters the final node, an increase in head losses is observed, which can have critical values depending on its increase. The introduction of additional water flows into the network, which exceed two nodal ones, requires the use of intermediate network nodes located at sections with a higher throughput as connection points. Originality. The analysis of the factors influencing the choice of points of connection of additional power sources of the water supply network during its expansion is carried out. The analysis of the points was carried out with limited ranges of the values of water consumption of additional feeding − less and equal to the nodal ones, two and three times larger than the nodal ones. The ways of finding the optimal option for choosing a network node as a point of connection of additional power are shown. Practical value. The use of the analysis results will make it possible to most effectively search for the optimal variant of reconstruction of water supply systems, take into account the influence of determining factors on the characteristics of networks with changes in water consumption and flow distribution. The use of the analysis results will make it possible to most effectively search for the optimal variant of reconstruction of water supply systems, take into account the influence of determining factors on the characteristics of networks with changes in water consumption and flow distribution.

Accessibility to safe drinking water is regarded as a fundamental human right since it is essential to preserving healthy livelihoods and the basic human dignity of all human beings. The study examined the effect of inadequate potable water supply on the health of the people in the Wa Municipality of Ghana. Findings of the study revealed that water related diseases are very common in the municipality due to the inadequate supply of potable water. About 55% of respondents, mentioned schistosomiasis as the top disease burden in the area. Again, the analysis of data on water provision and accessibility in the study suggested that most of the residents of the Municipality precisely 69.2% covered distances more than the standard distance of 1km stipulated by World Health Organization in search for potable water. The impacts of the time spent and distance traveled to acquire water in the Municipality were largely experienced by children and women, owing to the fact that in Ghana, water collection is considered to be the primary duty of children and women. Based on the findings the study recommends that more boreholes should be provided in the Wa Municipality to enable the residents have easy access to potable water supply. KEYWORDS: Ghana, Wa Municipality, Potable water accessibility.

Water is a basic human need that must be met every day. This results in the provision of water to be carried out even though the availability of raw water is limited. The limited availability of raw water is caused by the reduced water catchment area due to land conversion, the reservoir environment that has not been optimally conserved, and the reservoir as a reservoir for raw water which is not sufficient in number, even though the raw water in Tanjungpinang City comes from rainfall, so it is necessary to for the construction of a new reservoir. This research was conducted with the aim of knowing the management of resources by PDAM Tirta Kepri. This is because PDAM Tirta Kepri as a company engaged in the management, supply, and distribution of water to the community, thus has the responsibility to manage water resources. PDAM Tirta Kepri is a company that manages clean water which has been consumed by the people of Tanjungpinang. Even though it has been running so far, PDAM Tirta Kepri still needs to maximize the number of sales in order to meet the water needs of the people of Tanjungpinang city.

Harvesting water from untapped fog is a potential and sustainable solution to freshwater shortages. However, designing high-efficiency fog collectors is still a critical and challenging task. Herein, learning from the unique microstructures and functionalities of the Namib desert beetle, honeycomb, and pitcher plant, we present a multi-bioinspired patterned fog collector with hydrophilic nanofibrous bumps and a hydrophobic slippery substrate for spontaneous and efficient fog collection. Interestingly, hydrophilic nanofibrous bumps display a honeycomb-like cellular grid structure self-assembled from electrospun nanofibers. Notably, the patterned nanofibrous fog collector exhibits superior water-collecting efficiency of 1111 mg cm-2 h-1. The hydrophilic nanofibrous bumps increase the effective fog-collecting area, and the hydrophobic slippery substrate promotes quick transport of collected water in the desired direction reducing the secondary water evaporation, finally achieving rapid directional transport of tiny droplets and high-efficiency water collection. This work opens a new avenue to collect water efficiently and provides clues to research on the multi-bioinspired synergistical optimization strategy.

The infrastructure growth has an impact on reducing green areas, which will be followed by reduced water catchment areas. Porous concrete is one of the porous materials that can be used on a pedestrian walk, which is able to drain water. The porous concrete has a limitation strength. This research aims to determine the effect of using various content of chemical additive and polypropylene fibers for porous concrete mixtures related to the compressive strength and permeability values. This experimental method referring to ACI 522R-10 Standard. That specimens using chemical additives and variations of polypropylene fibers: 0.05%, 0.1%, 0.15%, 0.2%, and 0.25% by weight of cement. The results showed that the specimen which had the highest compressive strength was 16.9 MPa, which was added 0.25% polypropylene fiber. The addition of polypropylene fibers increases the compressive strength value by 5.6%. Based on the compressive strength and permeability graphs, it can be estimated that the optimal content of polypropylene fiber is 0.17% by weight of cement.

Multifunctional surfaces that are favorable for both droplet nucleation and removal are critical for water-harvesting applications, but there still remain great challenges. Herein, we proposed a facile strategy to construct hydrophobic surfaces containing moderate hydrophilic groups to achieve both exceptional droplet nucleation and removal. Different from natural desert beetle-inspired water-harvesting materials, these surfaces utilize limited hydrophilic domains to condense fog, and transport of formed tiny droplets relies on a hydrophobic background. The total surface area of the presented hydrophobic fabric contains hydrophilic groups, and the areas for trapping fog have increased. This feature is optimized to enhance the droplet nucleation density, and the surface still has excellent liquid repellency, resulting in maximum water collection efficiency of the prepared surface reaching up to 3.145 g·cm-2·h-1, much higher than the most reported water-harvesting materials. Due to its high efficiency and scalability, we believe that the proposed strategy to construct hydrophobic surfaces containing hydrophilic groups has great practical value.

Land use change have an impact on infiltration capacity. There is often an annual flood on Kadumanggu District. When the rainfall is high so the river will be overflow. The outlet of Cikeas sub-basin was located on Kadumanggu District. This research aimed to determine the maximum discharge of the Cikeas River and analyze the relation between land use change and discharge of Cikeas River. The research was conducted by delineating the water catchment area, analyzing rainfall, making a land use map and modeling with HEC-HMS. Based on the modeling results, the maximum discharge of the Cikeas River in 2000 was 74.3 m3/s, in 2009 was 84.9 m3/s, and in 2018 was 91.7 m3/s. The catchment area with an extensive use as residential had a higher river discharge compared to the area with a large green area. It meaned that, land use changes greatly affected the river discharge.

The Sacachún commune in Ecuador currently faces a lack of water for its agricultural development; this reduces its possibilities of socio-economic development and causes migration to urban areas. This research proposes a presa colinar (hill dam) design that uses ancestral knowledge and classic engineering techniques to promote water use during the dry season in semi-arid regions. The methodology consisted of: (i) a systematic compilation of the ancestral structures used for water planting and harvesting in Ibero-American; (ii) selecting an appropriate place to build the hill dam; (iii) the dam’s body design; (iv) and creating a proposal for agricultural water use. The results helped define a good location for the hill dam implementation. In addition, a 10 m high and 40 m wide earthen dam was designed, with a storage capacity of 114,341 m3, extending agriculture to 7.5 ha through a polyculture system of six different plants. The embankment has a cofferdam located downstream, which provides stability in static and pseudo-static conditions. In addition, the dam slopes have a 2:1 ratio, and a spillway channel and filter drain were dimensioned to protect the dam.

Water is used by bees for their metabolism and other functions in the colony. In the absence of water sources, it is essential to provide bees with a water station. In this paper we present the construction of a waterer and the preliminary results of the evaluation of the visitation for water collection in a waterer installed in an apiary and another one in an orchard cultivated under anti-hail screens. The number of bees arriving at the waterer per minute and their visitation time was evaluated. The bees visited the waterer constantly, in both environments, even in weather conditions considered inappropriate for flight and foraging, which shows the need for water for the colony. The installation of water stations in the orchards may be an option to improve the permanence of the bees under the anti-hail screens and to preventing that when they leave in search of water they cannot return. A água é utilizada pelas abelhas no seu metabolismo e outras funções na colônia. Na ausência de fontes de água é fundamental a disponibilização de um bebedouro às abelhas. Neste trabalho apresentamos a confecção de um bebedouro e os resultados preliminares de avaliação da visitação para a coleta de água em um bebedouro instalado em um apiário e outro em um pomar cultivado sob telas antigranizo. Avaliaram-se o número de abelhas que chegavam ao bebedouro por minuto e o seu tempo de visitação. As abelhas visitaram os bebedouros de forma constante nos dois ambientes, inclusive em condições climáticas consideradas impróprias para voo e forrageamento, o que demonstra a necessidade de água para a colônia. A instalação do bebedouro nos pomares pode ser uma opção para melhorar a permanência das abelhas sob a tela antigranizo, bem como evitar que elas não consigam regressar ao saírem em busca de água.

RW.8 and 9 areas, Blimbing Sub-district, Malang city is one of the areas that often occur inundation due to changes in land cover and narrowing of drainage channels. The solution is the manufacture of injection wells to determine the inundation, planning, and effectiveness of injection wells at the research site. To analyze it, modeling rain inundation a return period of 2 years and 5 years using Storm Water Management Model (SWMM) 5.1 application. Calibration results showed for the Root Mean Square Error (RMSE) value, modeling discharge and measurable discharge for a return period of 2 years is 17.3%, and a return period of 5 years is 20.9%. The simulation results showed the capacity of existing drainage channels for a return period of 2 years and 5 years resulted in 8 channels overflowing from 42 existing channels with the number of injection wells needed as many as 45 injection wells for 8 water catchment areas. The effectiveness value of the application of injection wells using rain barrels obtained results for a return period of 2 years is 66.67%-93.33% with average injection well effectiveness is 84.66% and a return period of 5 years is 66%-95% with average injection well effectiveness is 84.78%.Â

Draining galleries are water collection systems that occurs frequently in various geomorphic contexts of semi-arid environments. In this article, we study those that take advantage of subalveal waters by means of different construction techniques, mainly 'cimbras' and 'cimbra-zanjas'. A comparison has been made between the Tunisian galleries and those of the Spanish SE that have these two characteristics: the exploitation of subsubalveal waters and surface detritic aquifers, and rainfall characteristics of semi-arid climates, specifically annual total rainfall between 300 and 400 mm. The work analyzes the environmental contexts of the selected galleries, especially geology, geomorphology, rainfall torrentiality and hydrology, as well as the constructive, functional characteristics and conservation status of the galleries. The results of the comparative analysis show that there are no significant differences between the galleries of both territories, neither in the necessary environmental conditions, nor in the constructive and functional characteristics adopted. Las galerías drenantes son sistemas de captación de aguas que se presentan con frecuencia en variados contextos geomórficos de ambientes semiáridos. En este artículo se estudian aquellas que aprovechan aguas subálveas mediante diferentes técnicas constructivas, principalmente cimbras y cimbra-zanjas. Se ha realizado una comparación entre las galerías tunecinas y las del SE español que presentan estas dos características: la explotación de aguas subálveas y de acuíferos detríticos subsuperficiales, y una pluviometría propia de climas semiáridos, en concreto unas lluvias totales anuales entre 300 y 400 mm. En el trabajo se analizan los contextos ambientales de las galerías seleccionadas, sobre todo geología, geomorfología, torrencialidad de la lluvia e hidrología, así como las características constructivas, funcionales y estado de conservación. Los resultados del análisis comparado muestran que no existen diferencias significativas entre las galerías de ambos territorios, ni en las condiciones ambientales necesarias, ni en las características constructivas y funcionales adoptadas.

Access to a sufficient quantity of safe water is widely recognized as fundamental to ensure health and prevent water- and excreta-related diseases. The objective of this study is to analyze seasona...

Droplet manipulation plays an important role in scientific research, daily life, and practical production such as biological and chemical analysis. Inspired by the structure and function of three typical leaf veins, the bionic texture was replicated by the template method, and the artificial leaf was selectively treated by nanoparticles to obtain a quasi-three-dimensional hybrid superhydrophobic-hydrophilic surface. When the droplet touches the surface of the leaf, it will be attracted to the bottom of the main vein from different directions even in horizontal conditions due to the Laplace pressure gradient and energy gradient. The simulation analysis demonstrates that the reason for directional transportation is the energy gradient of the droplets on the different levels of veins, including the thin veins, lateral veins, and main vein. Meanwhile, the experimental result of water collection also showed an outstanding directional transportation effect and excellent water collection efficiency. In addition, when the sample is tilted upside down, the droplet will flow back to the main vein along the lateral vein and then flow down the main vein, showing a good droplet pumping effect. Therefore, the directional and polydirectional transportation of droplets on the same sample is successfully realized, and the conversion between executing single and multiple tasks simultaneously can be realized only by upright and inverted samples. This work provided a new strategy for directional and polydirectional water manipulation, water collection, directional drainage, and microfluidic devices.

The feasibility study is one of the principal documents in building a hydropower plant consisting of technical, economic, and financial aspects. Contained technical studies on civil, mechanical, and electrical. This requires data on hydrologic, geology, land contours, river discharge, water catchment areas, and so on. Economic and financial studies include cost and financial parameters such as; BEP, IRR, NVP, BCR, and others. The installed capacity of a hydropower plant is given in optimization based on the Flow Duration Curve (FDC) and the Capacity Factor (CF) used the Newton Interpolation Method. The results showed that the installed power capacity was 11.99 MW. The water discharge was 31.603 m3/secs and the effective head was 37.5 meters. Annual income is around IDR 103.026 billion. Finally, HPP Lubuak Gadang is technically, economically, and financially feasible, so it is feasible to carry out the next process.

Increasing and developing infrastructure in urban areas has resulted in decreased water infiltration quality into the ground. The increasing of settlement needs and raising its price has resulted in many water catchment areas changing their function unconsciously in urban areas. This condition was ultimately triggering the loss of opportunities for rainwater to into the ground. At present, when the rainy season arrives, almost all major cities in Indonesia experience flooding. The torrential rains that lasted just 1 hour were enough to cause relatively high inundation, which varied from 30 cm to over 1m. This study aims to analyze the intensity of rainfall and its impact on the potential for flooding in urban areas and how to overcome it by utilizing rooter system technology. The results showed that the 4-way rooter system technology's influence was considerable in reducing the water level. An experimental area of 100 m2 treated with a rooter system of 16 pipes with a water level of 40 cm can infiltrate stagnant water into the soil within 120 minutes. Meanwhile, in the same area without rooter technology, it takes 400 minutes to absorb water into the soil until the stagnant water is completely gone. This proves that the rooter system technology plays a significant role in accelerating water absorption into the ground, reducing the risk of flooding.

The shortage of fresh water resources is becoming more and more serious with the acceleration of modernization and industrialization, especially in some dry welding and underdeveloped areas. Scientists are bent on alleviating the issue of fresh water shortage. Concurrently, many biological species have developed elegant schemes for water-harvesting for their survival. Combining their mechanisms and design strategies is crucial to fabricate interfacial materials with efficient water collection. This paper extracts the water-collecting principles and characteristics of Namib Desert beetles, cactus and spider silk, and reviews the synthesis strategies of various bionic water collecting materials under the guidance of these typical creatures. We put an extreme emphasis on the liquid–solid interfacial interaction between the accumulative nuclear dew and functional materials' surfaces. The key factor for reliable water collection materials is the design of robust hierarchical configuration. However, these constructed microstructures are vulnerable and many practical applications are limited. Therefore, the design of architectures with durability has become a serious topic and we highlight the development, current research status on the durability and self-repair of directional water collection materials. Finally, a holistic view and future prospects of bionic directional water collection materials, including mechanisms, characterization, design strategies and fabrication techniques, are provided. We envision that these well-chosen facts and opinions will be useful in fluid handling and transportation, self-cleaning and water collection fields.

Fog is an underestimated source of water, especially in regions where conventional methods of water harvesting are impossible, ineffective, or challenging for low-cost water resources. Interestingly, many novel methods and developments for effective water harvesting are inspired by nature. Therefore, in this review, we focused on one of the most researched and developing forms of electrospun polymer fibers, which successfully imitate many fascinating natural materials for instance spider webs. We showed how fiber morphology and wetting properties can increase the fog collection rate, and also observed the influence of fog water collection parameters on testing their efficiency. This review summarizes the current state of the art on water collection by fibrous meshes and offers suggestions for the testing of new designs under laboratory conditions by classifying the parameters already reported in experimental set-ups. This is extremely important, as fog collection under laboratory conditions is the first step toward creating a new water harvesting technology. This review summarizes all the approaches taken so far to develop the most effective water collection systems based on electrospun polymer fibers.