Water Supply

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Assessing Future Water Demand and Associated Energy Input with Plausible Scenarios for Water Service Providers (WSPs) in Sub-Saharan Africa
(Multidisciplinary Digital Publishing Institute, 2021-04-13) Macharia, Pauline; Kitaka, Nzula; Yillia, Paul; Kreuzinger, Norbert
This study examined the current state of water demand and associated energy input for water supply against a projected increase in water demand in sub-Saharan Africa. Three plausible scenarios, namely, Current State Extends (CSE), Current State Improves (CSI) and Current State Deteriorates (CSD) were developed and applied using nine quantifiable indicators for water demand projections and the associated impact on energy input for water supply for five Water Service Providers (WSPs) in Kenya to demonstrate the feasibility of the approach based on real data in sub-Saharan Africa. Currently, the daily per capita water-use in the service area of four of the five WSPs was below minimum daily requirement of 50 L/p/d. Further, non-revenue water losses were up to three times higher than the regulated benchmark (range 26–63%). Calculations showed a leakage reduction potential of up to 70% and energy savings of up to 12 MWh/a. The projected water demand is expected to increase by at least twelve times the current demand to achieve universal coverage and an average daily per capita consumption of 120 L/p/d for the urban population by 2030. Consequently, the energy input could increase almost twelve-folds with the CSI scenario or up to fifty-folds with the CSE scenario for WSPs where desalination or additional groundwater abstraction is proposed. The approach used can be applied for other WSPs which are experiencing a similar evolution of their water supply and demand drivers in sub-Saharan Africa. WSPs in the sub-region should explore aggressive strategies to jointly address persistent water losses and associated energy input. This would reduce the current water supply-demand gap and minimize the energy input that will be associated with exploring additional water sources that are typically energy intensive.
COVID-19 pandemic: Water, sanitation and hygiene (WASH) as a critical control measure remains a major challenge in low-income countries
(2021-03-01) Donde, Oscar Omondi; Atoni, Evans; Muia, Anastasia Wairimu; Yillia, Paul T.
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the deadly respiratory disease called coronavirus disease of 2019 (COVID-19), an ongoing global public health emergency that has been declared a pandemic by the World Health Organization. We review literature on the transmission and control of SARS-CoV-2 and discuss the challenges of focusing on water, sanitation and hygiene (WASH) as critical control measures in low-income countries. A significantly higher prevalence of SARS-CoV-2 infection and COVID-19 related deaths has been reported for the United States of America and other high-income countries in Europe and Asia, regardless of advanced medical facilities in those countries. In contrast, much lower COVID-19 related morbidity and mortality rates have been documented in many low-income countries, despite having comparatively higher socioeconomic burdens and suboptimal medical facilities. By September 29, 2020 over one million deaths have been reported. On the same day, the cumulative total of COVID-19 related morbidity for Africa was 35,954 with 3.5% of the global COVID-19 related deaths. We present arguments for the relatively low COVID-19 morbidity and mortality rates in many low-income countries and discuss the critical importance of WASH for preventing the spread of infectious diseases like COVID-19. We observe that the key recommendations put forward by the World Health Organization to effectively control the pandemic have been difficult to implement in low-income countries. We conclude that the pandemic reinforces previous pronouncements that adequate and effective WASH measures are crucial for public health and recommend closer coordination between public health and WASH sectors.
First record of dwarf Victorian mouthbrooder Pseudocrenilabrus multicolor victoriae (Schöller, 1903) in Lake Naivasha, Kenya, including data on its molecular identification: Management implications
(John Wiley & Sons ltd, 2018-09-30) Otachi, Elick O.; Rindoria, Nehemiah M.; Medhanit, Meri M.; Ayeka, Peter A.; Wąs-Barcz, Anna
The present study describes the first record of 83 Dwarf Victorian mouthbrooder (Pseudocrenilabrus multicolor victoriae Seegers, 2000) newly discovered in Lake Naivasha, Kenya, in January 2016. Membership of the species was determined on the basis of morphometric characteristics and molecular analysis. The average length (±SD) of the fish was 6.95 ± 0.86 cm, and average weight was 5.59 ± 1.99 g. The body is normal/fusiform, the dorsal head profile convex-shaped, the mouth is terminal with bright blue lips, and the anal fin with a reddish tip, being distinctive features of the fish. The sequences of subunit I cytochrome oxidase (COI) and cytochrome b (cyt b) genes obtained in the present study were compared with records deposited in BoldSystem and NCBI databases. Using two genetic markers enabled unambiguous determination of the species membership. The queried specimen was assigned to the Cichlidae family, as Pseudocrenilabrus multicolor victoriae (100–96.68% similarity). These results constitute the baseline study for this fish in Lake Naivasha.
Hydraulic and clogging characteristics of Moistube irrigation as influenced by water quality
(IWA, 2018-06-12) Kanda, Edwin Kimutai; Mabhaudhi, Tafadzwanashe; Senzanje, Aidan
Irrigation consumes approximately 70% of total freshwater use worldwide. This necessitates the use of efficient irrigation methods such as micro-irrigation. Moistube irrigation (MI) is a new subsurface irrigation technology where the water emits from a semi-permeable membrane of the Moistube at a slow rate depending on the applied pressure and soil water potential. There is currently limited information on the performance of Moistube tapes with respect to discharge as a function of pressure or water quality. The aim of this study was to determine the flow characteristics of Moistube tapes as a function of pressure and the effect of suspended and dissolved solids on the emission characteristics. The pressure–discharge relationship was determined within a range of 20 kPa and 100 kPa. The clogging of the Moistube was determined using water containing low, moderate and high concentrations of suspended and dissolved solids at 20 kPa and 30 kPa. The results indicated that the Moistube discharge follows a power function with the applied pressure. The discharge decreased linearly over time because of clogging. Suspended solids had a more severe clogging effect on Moistube than dissolved solids. The results of this study should help in the design, operation and maintenance of MI systems.
My Water, My Choice! The Role of Citizens in Ensuring Equitable Access to Water in Soweto East Village—Nairobi
(Research Gate, 2016-01) Walubwa, Jacqueline
The chapter highlights the local governance structure of disenfranchised citizens and their role in self-mobilization to enforce democratic innovations in governing their water resources, an important issue confronting the governing of urban Africa. In the wake of lack of accomplishment of the Millennium Development Goals, these failures manifest themselves in the form of competition for urban services with an increasingly high rate of inequality between planned and unplanned settlements, further depicting a lack of leadership in policy implementation and political goodwill of the governance systems in upholding the sustainability agenda. Ethnographic surveys and interviews were used to acquire information relevant to the study and indicate that citizen empowerment is a panacea to development.
Rendering local commons sustainable : an informal water and sanitation context
(Adonis & Abbey Publishers Ltd, 2019-03-01) A. Walubwa, Jacqueline
Governing common property suggests that strict governance systems be put in place to sustainably and resiliently ensure that institutions have a long-standing tenure. The outcomes of each institution vary depending on the collective action bestowed and the local arrangements. The action is highly dependent on the rational choice of the community actors, who strategically choose to see that their cooperative behaviours will act to the advantage of their common property. This can only occur in a climate of trust and reciprocity in polycentric systems which are self-governed. This paper suggests using Ostrom’s design principles to govern local, human-made common property and further proposes the features that make for resilient informal systems. This theory is tested using an informal water and sanitation system as well as reviewing literature from second generation scholars.
Rural Water Supply in the Era of Climate Change in Kenya; The Case of Kapseret Sub County, Uasin Gishu County | African Journal of Education,Science and Technology
(African Journal of Education, Science and Technology (AJEST), 2023-04)
There is a perception that water supply in Uasin Gishu County is reliable due to the medium to high annual rainfall amounts received in the region. However, this is not the case as rainfall is not evenly distributed throughout the year. Consequently, many rural households experience water shortage in the dry season. The aim of the study was to assess reliability and evaluate the safety of domestic water sources in Kapseret Sub County. Questionnaires were used to collect data from 404 households selected randomly from four wards in the rural part of Kapseret Sub-County and the data subjected to frequency analysisprocedure. The study established that domestic water sources include; shallow wells (92.2%), rainwater (14.4%), river (8.2%), stream (5.2%), borehole (2.0%), piped water (3.9%), dams (2.0%) and springs (1.0%). An average 44.8% of the households’ experience seasonal water shortage. Distance to main water sources increases from an average of 22.3 meters in the rainy season to an average of 216 meters in the rainy season. As a result, households have adopted various water conservation strategies in the dry seasons including reusing water, cleaning house and clothes periodically, watering animals and cleaning clothes at the water point, and using little amounts of water for the various activities. About 36.6 % of households use water from unprotected water sources in the rainy season compared to 41.1% in the dry season, and therefore the water is prone to contamination. An average 63.6% of the households fetch water manually from the source using rope and container, with only 28.7% storing water in tanks. In conclusion, water security is yet to be achieved in the area of study. It was recommended that there is need for sound investment by national and county governments towards reliable water supply in rural areas.
Soil water dynamics under Moistube irrigation
(Elsevier, 2020) Kanda, Edwin Kimutai; Senzanje, Aidan; Mabhaudhi, Tafadzwanashe
The design and management of irrigation systems require knowledge of soil water movement. There are few studies on soil water dynamics of Moistube irrigation (MTI) since it is a relatively new type of subsurface irrigation technology. It was hypothesised that soil texture influences soil water distribution under MTI. We determined soil water distribution, experimentally and numerically, using HYDRUS 2D/3D model for two soil textures (loamy sand and sandy clay loam). The experiment consisted of a soil box filled with soil and Moistube, supplied with water under a constant pressure head of 60 kPa, placed at 20 cm below the soil surface. Soil water content (SWC) was measured using Decagon MPS-2 sensors installed at depths of 5 cm, 10 cm, 15 cm, 20 cm, 30 cm, 40 cm and 50 cm and laterally at 10 cm, 20 cm and 30 cm over a period of 72 h. Results showed that simulated SWC closely matched (R2 ≥ 0.70 and RMSE ≤ 0.045 cm3 cm−3) observed values for all depths considered for the two soil textures. The model slightly under- or over-estimated SWC (<15.6%). There was no significant difference (p > 0.05) between the soil water distribution in lateral and downward direction for both sandy clay loam soil and loamy sand. However, the SWC upward of the Moistube placement depth was significantly (p < 0.05) lower than both lateral and downward. SWC in loamy sand at 10 cm upward, downward and lateral after 24 h were 0.08 cm3 cm−3, 0.23 cm3 cm−3 and 0.20 cm3 cm−3, respectively. The corresponding values for sandy clay loam were 0.28 cm3 cm−3, 0.32 cm3 cm−3 and 0.31 cm3 cm−3 at 10 cm upward, downward and lateral, respectively. The simulations for wetted distance in both soil textures were also close to the observed values (R2 ≥ 0.97, RMSE ≤ 3.99 cm). Soil texture had a significant (p < 0.05) effect on soil water movement with upward movement faster in sandy clay loam than in loamy sand. The lateral and downward distances were 23 cm and 24.6 cm, respectively, for loamy sand after 24 h. Similarly, for sandy clay loam, the lateral and downward distance was 19 cm. These wetting distances should be considered in the design of MTI in terms of depth of placement and lateral spacing. The results of this study demonstrated the usefulness of HYDRUS-2D/3D model in the prediction of soil water movement for optimum design of MTI.
SYNTHESIS: SMART RAINWATER HARVESTING, STORAGE AND DISTRIBUTION TO ENHANCE WATER SECURITY
(Research Publish Journals, 2023-05-05) Okemwa, Sam; Kiprono, Kelvin; Matuku, DR Eng Peter; Kiptum, DR Eng Clement; Kipkorir, Prof Eng Emmanuel
Abstract: This paper presents a novel approach to establish water security through autonomous rainwater harvesting, storage, and distribution mechanisms. The primary focus of the research is on developing a reliable and cost-effective method for harvesting, storing, and distributing rainwater in an autonomous manner, whereby the system is self-regulating in terms of harvesting, storing, and distributing water in response to localized and customized needs or conditions, more especially to communities that are struggling to meet their minimal water demands. The paper aims to develop an integrated and automated system that is capable of collecting, storing, and distributing rainwater in a sustainable manner, with the goal of increasing water security in areas with limited or unreliable water supply as exhibited in arid and semi-arid lands or places with poor water infrastructure conditions. The research will initially explore existing rainwater harvesting systems, including both conventional and innovative designs, in order to identify the most effective methods for harvesting rainwater. This will include looking at appropriate storage, filtration and distribution systems, as well as considering the economic, environmental, and social impacts of these systems, identifying the benefits and drawbacks of their system design deployment. Following this, the research will focus on developing an autonomous rainwater harvesting system that is capable of responding to economic, environmental and social factors in an efficient and cost-effective manner. This will involve the development of an integrated and automated system for collecting, storing and distributing rainwater, with an emphasis on sustainability and water security. The research will consider issues such as water scarcity, resource management, and environmental protection in order to ensure that the autonomous rainwater harvesting system is designed with these considerations in mind. Additionally, it will analyze the cost-effectiveness of the proposed system, and explore potential areas of application for the system. Finally, the paper will provide an assessment of the overall impact of the autonomous rainwater harvesting system on water security and consider the potential for further development and improvement of the system if sustainable. Keywords: rainwater harvesting, distribution mechanisms, distributing water, water security. Title: SYNTHESIS: SMART RAINWATER HARVESTING, STORAGE AND DISTRIBUTION TO ENHANCE WATER SECURITY Author: Sam Okemwa, Kelvin Kiprono, DR. Eng. Peter Matuku, DR. Eng. Clement Kiptum, Prof. Eng. Emmanuel Kipkorir International Journal of Civil and Structural Engineering Research ISSN 2348-7607 (Online) Vol. 11, Issue 1, April 2023 - September 2023 Page No: 32-37 Research Publish Journals Website: www.researchpublish.com Published Date: 05-May-2023 DOI: https://doi.org/10.5281/zenodo.7898522 Paper Download Link (Source) https://www.researchpublish.com/papers/synthesis-smart-rainwater-harvesting-storage-and-distribution-to-enhance-water-security
Vulnerability Assessment of Sustainable Drinking Water Supply and Development in a Changing Climate in Nakuru Town, Kenya
(East African Journal of Environment and Natural Resources, 2019-12-24) Keli, Margaret Mwikali; Munyao, Thomas Mutuku; Kipkorir, Emmanuel C.; Shakala, Edward Kokan
The close connection between the climate and the hydrological cycle makes climate change to have a significant impact on water resources with regard to variability, distribution and occurrence. Research wise, climate change has assumed increasing importance from the perspective of development compared to the water environment. In Kenya, key water-related issues facing the country are the effects of climate variability and the steady degradation of the nation’s water resources. Limited research has focused on alleviating the problem as the effects of the water crisis remain wider, deeper and more uncertain requiring immediate attention. Major indicators of existing problems are manifested in lack of information and knowledge on climate-induced changes under natural variability conditions in drinking water regimes, quality, quantity, human health and likely future changes. The study uses a scientific approach based on hydrological analysis focusing on the link between changing climate conditions and drinking water quality and supply issues in Nakuru Municipality. Primary data collection employed measurement and analysis of selected inorganic drinking water quality variables with significant risk to health in the area’s local natural conditions. To explore short and long-term trends of climatic change indicators and their effect on the area’s hydrology, statistical trend analysis of rainfall for a period of 45 years was used. Temperature data used covered a period of 36 years. Water samples were taken to represent important water source points for public supply for ten months (June 2014 to March 2015) and analysed in accordance with standard methods. Data were analysed by trend analysis, descriptive and correlation techniques. Strong, weak and negative trends were observed between water quality variables and rainfall variability. Results show that temporal and spatial variability of rainfall patterns and temperature in the area of study affect surface and groundwater recharge processes, water table, quality, quantity and supply issues. According to the study, the effects of drinking water crisis linked to climate variability and change in terms of prediction methods, frequency, and rate of change, quality and quantity are wider, deeper and more uncertain requiring immediate attention. The existing challenges limit sustainable development, effective long-term planning and management of the areas drinking water resources. The results can be valuable in characterizing and addressing the study area’s water quality conditions and trends.

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