Water

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Access to Water in Kenya’s Coast Region: A Challenge to Community Development and Poverty Alleviation in Lamu County
(Kenya Aquatica Journal, 2018-11-30) Ignatius, David O.; Hassan, Farida A.; Morara, George N.; Osore, Melckzedeck K.; Mutua, Benedict; Kitaka, Nzula K.
Water is considered a basic commodity and essential for life - living on planet earth is dependent on it. However, access to water has been and will continue to be a dilemma for a majority of the residents at the coast of Kenya. A close look at the window on “Coastal Resources and People” reveals that water is a key resource but despite its immense importance, many people especially in the rural areas and the Vulnerable and Marginalized Groups (VMG’s) do not have adequate access to potable, reliable and convenient sources of water. Lamu, currently considered among water scarce counties in Kenya as per the Lamu County Integrated Development Plan (http://lamu.go.ke/wp-content/uploads/2016/03/LAMU_CIDP-Revised.June_2014-1.pdf), faces serious challengeof provision of potable water to its residents. With the influx of people from other parts of the country as a result of the implementation of the Kenya Vision 2030 flagship project - Lamu Port Southern Sudan Ethiopia Transport Corridor (LAPSSET), the current water stresses is only expected to worsen. The Lamu County Government plans to address the ever-increasing demand for access to water but resources to actualise these plans are yet to be consolidated. To complement this situation, Kenya Coastal Development Project (KCDP), a World Bank funded project is working with local communities in Lamu in thedevelopment and implementation of community-led water projects targeting to increasing access to water at household level.This paper will focus on community-based approaches to understand the water-web in Lamu East Sub-County to provide an assessment of opportunities, challenges and sustainability implications. Primary data is used on surveys, Social Assessment (SA) Vulnerable and Marginalised Group Plan (VMGP), observations and recommendations from the Lamu CIDP. It further proposes that of direct usage of saline water, seawater or brackish water, for sanitation purposes could alleviate the freshwater shortage.
Analysis of Constituent Chemicals and their Effects on the Physico-Chemical Properties of Spring Water in Ngariama location Gichugu Division Kirinyaga County of Kenya
(Journal of Natural Sciences, 2013-08) Ngari, Mwaniki; Wanjau, Tabitha; Njeru, Sospeter
Keywords: Ground water, Gichugu division has numerous springs, which are a manifestation of potentially high volumes of groundwater. This water is characteristically different from river water in terms of physical parameters like fizzling, characteristic taste and clarity chemistry was studied to explain the above differences. The study established that groundwater in Gichugu area is slightly a (pH 6.49), moderately hard (123.99 mg/l CaCO Cl-). These salts and the pH explained the taste of the water. Also, NaCl and other ionic compounds accounted for the relatively higher conductivity (4.700 Ec µS/cm) while such ions as Ca The percolation of this water through the surface soils of recharge areas generally results in significant purification hence clarity. Fizzling was as a result of dissolved gases such as carbon dioxide and oxygen as they escaped. It was also established that a common groundwater aquifer underlies the area. Iron (0.426 mg/1) and manganese (0.322 mg/1) were found in excess of WHO recommended limits (0.3 mg/1 and 0.1 mg/1 respectively) for potable water quality while fluoride was in relatively low amounts (0.642 mg/1). However, their levels in this water do not make this water unsuitable for drinking since they are still within the acceptable tolerance levels.
Analysis of spatial and temporal drought variability in a tropical river basin using Palmer Drought Severity Index (PDSI)
(Acadamic Journals, 2017-08-31) Wambua, Raphael; Mutua, Benedict; Raude, James
Analysis of spatial and temporal drought variability in the upper Tana River basin using Palmer Drought Severity Index (PDSI) was conducted. The drought is critical for formulation of mitigation measures in the river basin. A monthly temporal and 90-m spatial resolution was applied. This was achieved within ArcGIS environment. Climatic data for 1970 to 2010 was used for computation of the PDSI while the missing data sets were filled using Artificial Neural Networks (ANNs). The results of PDSI for dry and wet seasons at meteorological stations indicate that the time series plots for the PDSI values for dry season are generally lower than those for the wet seasons. The PDSI values for meteorological stations located at the lower elevation of the basin are lower than those located at higher elevation. On the other hand, spatially distributed drought severity based on PDSI show that the ranges of maximum and minimum drought severity values in 1970 are -0.868 to -0.804 and -0.675 to -0.610 respectively. These values of drought severity occur respectively in the north-western and south-eastern areas of the basin. PDSI values increased from the range -0.675 to -0.610 in 1970 and from -1.087 to 0.957 in 2010 for the north-eastern areas of the upper basin. The south eastern areas of the basin are more prone to drought risks than north-western parts. Use of the PDSI reflects the spatial heterogeneity and temporal variability of drought across the basin. The drought assessment offer technical approach for comprehensive understanding of drought for effective drought-induced disaster mitigation and its management, with a view to reducing adverse effects on livelihoods.
Antibacterial effect of Solanum incanum root extracts on bacteria pathogens isolated from portable water in Egerton University, Kenya
(BioMed Central, 2019) Waithaka, Paul; Githaiga, Benson; Gathuru, Eliud; Dixon, Mojong
Background: Contaminated water is a major source of enteric diseases. This study aimed at isolating pathogenic bacteria from portable drinking water in Egerton University. In addition, the study aimed at subjecting the isolates to sensitivity test of root extracts from Solanum incanum besides carrying out minimum inhibitory test of the root extracts. Material and methods: The bacterial pathogens were isolated from water using membrane filtration. The roots were obtained from Solanum incanum plants in the field and dried at room temperature under shade. The root extracts were obtained using methanol, ethanol and water. Sensitivity test of the isolates to the extracts was carried out using disk diffusion technique. Minimum inhibitory technique was carried out using broth tube dilution technique. Results: The bacterial pathogens such as Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and Klebsiella sp. were isolated from the water samples. The crude extracts contained tannins, alkaloids, glycosides, flavonoids, resins, phenols and steroids. There was no significant difference between the zones of inhibition produced by the test bacterial pathogens when subjected to crude extracts obtained using methanol, ethanol and water (F=28.57 P=0.07). However, there was a significant difference between the MIC of methanol, ethanol and water extracts. Conclusion: Portable water in and around Egerton University is contaminated with potential bacteria pathogens. However, extracts from Solanum incanum can be used as a remedy to the problem. There is need for determination of the structure of active ingredients in the extracts obtained from Solanum incanum.
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.
Assessment of Kangemi sewage treatment works efficiency and the impact of the effluent on water quality of Chania River Nyeri, Kenya
(Egerton University, 2019-10) Kariunga, Saeed Hassan
Sewage treatment plants (WTPs) use a combination of physical, chemical and biological processes to reduce the pollutant loads in wastewater. The treated wastewater is then either discharged to surface water or is reused. Successive stages in wastewater treatment plants reduce the quantity of suspended solids, biological contaminants, organic matter content and nutrient constituents in sewage. Changes in the properties of the effluents can occur along the treatment process leading to reduction or little change in effluent quality based on the effectiveness of the treatment process. The discharge of inadequately treated sewage from ineffective WTPs into the rivers and other receiving water bodies are both potential health risk and environmental hazard to both adjacent and downstream communities. This study estimates the efficiency of Kangemi Sewage Treatment Works (KSTW) in pollutant removal and the impact of its effluent on water quality of Chania River (CR). For environmental quality assurance, the plant’s performance requires consistent monitoring to evaluate the impact of the effluents to the receiving waters. Key nutrients (Nitrogen and Phosphorus), total suspended solids (TSS) and biological oxygen demand (BOD5) were determined using American Public Health Association (APHA, 2005) standard methods. Kruskal-Wallis test was run at p<0.05. Nitrogen, BOD5 and TSS indicated a significant difference between the sites (P<0.05). Physico-chemical parameters varied significantly, however, no significant difference for TP (Kruskal Wallis, 4.515, P=0.341) and SRP (Kruskal Wallis, 2.160, P=0.696) respectively across sites in KSTW. Removal efficiency for BOD5, TSS, NH4 and TN were 60%, 85%, 59% and 54% respectively. The KSTW had high removal efficiency for N but low for P but it was a source of nitrate, nitrite and TP. Organic-N was the most dominant form of N in KSTW, while P was mostly inorganic. In CR, the confluence (S8) recorded highest concentrations for most parameters (N, P, BOD5 and TSS). Inorganic-N in the CR was more than organic-N after effluent discharge point. Nitrate-N was the most common species of the dissolved nitrogen in CR. All parameters measured in CR showed a significant difference except TSS (Kruskal Wallis, P=0.733). Nutrients and organic matter in both the KSTW and Chania River indicated a strong correlation with temperature, DO and pH. Both for N and P, the organic form was dominating in CR. In conclusion, Pollution impact was highest at the KSTW point of effluent discharge (S8), with, the river indicating quick recovery downstream. In contrast, TSS indicated a progressive increase in concentration downstream from S8-S10. For recommendation, long-term surveys should be conducted to capture temporal efficiency and impact of KSTW effluent on Chania River.
Assessment of physico-chemical characteristics of groundwater among different farm sizes in Ainabkoi sub-county, Uasin Gishu County, Kenya
(Acadamic Journals, 2018-11-30) Kitonga, Lydia Mbula; Moturi, Wilkister Nyaora; Mwonga, Samuel Mutuku; Taabu, Isaiah
Access to quality drinking water is of major concern for sustainable development in developing countries with regard to physico-chemical properties. Groundwater from shallow wells is the main source of domestic water supply for the community of Ainabkoi Sub-County of Uasin Gishu County in Kenya. Seasonal agricultural production activities expose the water to possible pollution. In this regard the study aimed to assess the seasonal physico-chemical parameters in shallow wells among different farm sizes in three wards within Ainabkoi sub-county. Each ward was a homogenous stratum of same size-ranged farms classified as large, medium and small farm sizes in Ainabkoi, Olare and Kaptagat (Kipsinende) wards respectively. Within each ward farms were purposively and randomly selected such that only accessible farms that had access to either a privately owned or communal wells were selected. Wells were sampled during the wet and dry seasons of the year for a period of two years. The seasonal levels of physico-chemical parameters pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Dissolved Oxygen (DO), Total Suspended Solids (TSS), turbidity and temperature were determined. There were non-significant differences between the farm sizes in the groundwater pH, EC, DO, turbidity and temperature. The groundwater pH values were within the WHO standards range of 6.3 to 8.5. EC values were below the recommended limits of potable water of 250 µccm-1. TDS and TSS differed significantly between farm sizes. Wells within the small mixed farm sizes had significantly high TDS levels ranging from 30-250 mgL-1. The TDS values ranged from 32.20-203.30 mgL-1 hence the wells can be classified as fresh water wells. TSS values were significantly higher during the wet season by about 90% and highest in wells within the large sized farms. The turbidity levels were higher than the recommended limits by WHO of at least 5.0 NTU in areas with limited resource availability. In conclusion, the groundwater in Ainabkoi sub-county can conservatively be categorised as safe for domestic use with regard to physico-chemical parameters. Key words: Farm sizes, groundwater, season; physico-chemical properties.
Can Sanitary Surveys Replace Water Quality Testing? Evidence from Kisii, Kenya
(MDPI, 2017-02-07) Misati, Aaron Gichaba; Ogendi, George; Peletz, Rachel; Khush, Ranjiv; Kumpel, Emily
Information about the quality of rural drinking water sources can be used to manage their safety and mitigate risks to health. Sanitary surveys, which are observational checklists to assess hazards present at water sources, are simpler to conduct than microbial tests. We assessed whether sanitary survey results were associated with measured indicator bacteria levels in rural drinking water sources in Kisii Central, Kenya. Overall, thermotolerant coliform (TTC) levels were high: all of the samples from the 20 tested dug wells, almost all (95%) of the samples from the 25 tested springs, and 61% of the samples from the 16 tested rainwater harvesting systems were contaminated with TTC. There were no significant associations between TTC levels and overall sanitary survey scores or their individual components. Contamination by TTC was associated with source type (dug wells and springs were more contaminated than rainwater systems). While sanitary surveys cannot be substituted for microbial water quality results in this context, they could be used to identify potential hazards and contribute to a comprehensive risk management approach.
Characteristics, disposal methods and management of plastic waste in Watamu, Kilifi County, Kenya
(Egerton University, 2019-04) Gwada, Brenda C.
Plastic waste has been and still is a major challenge and concern globally but more so in the developing countries. Plastic has been shown to impact negatively on marine life more specifically marine animals. Watamu ward, in Kilifi County, Kenya, is an important breeding ground for the critically endangered turtles and is being affected by plastic waste. The aim of this study was to assess the characteristics, disposal methods and management of plastic waste in Watamu, in order to contribute to an understanding of the plastic waste disposal practices in the country. The specific objectives were to characterize the plastic waste in Watamu, as well as their streams. Secondly, the study also assessed the factors influencing level of knowledge, attitude and perception among the general public with respect to plastic waste disposal. Thirdly, the study determined the factors that influence plastic waste disposal methods. Finally, the study assessed and described the existing plastic waste management methods in the study area. A social survey was conducted to characterize plastic waste and determine the existing plastic waste management methods in the study area. Stratified random sampling design was used to divide the population of Watamu into groups based on their sub-locations and simple random sampling was used to arrive at the sample for this study. Primary data were collected using observation, structured questionnaire and semi-structured interviews and secondary data from various sources. The data were analysed using descriptive and inferential statistics. The results show that 55.4% of the plastic waste discarded was low density polyethylene that was discarded by the public who were responsible for 69.3% of the plastic waste found discarded. According to the results, 50.7% of plastic wastes were disposed of at the open dumpsite at Timbotaka, in Watamu sub-location. Location of the respondents was a significant factor that influenced the level of knowledge, attitude and perception with respect to plastic waste disposal (FH = 25.729, p = 0.002; FH = 16.289, p = 0.033; FH = 24.145, p = 0.009). It also influenced the plastic waste disposal methods used by respondents (FH = 50.708, p = 0.000). Other factors that influenced plastic waste disposal methods include occupation FH = 30.082, p = 0.038), waste collection and presence of recycling centres. The existing plastic waste management methods are re -use and small-scale re-cycling done by locals and Eco-world respectively. In conclusion, the proximity of waste disposal sites determines the plastic waste disposal methods used by the locals. Therefore, for environmentally-sound management of plastic waste, disposal sites should be easily accessible. Further awareness campaigns and public education need also to be done on plastic waste management to facilitate proper disposal methods.
Characterization of anthropogenic activities influencing surface water quality along molo river ecological system, Kenya
(Ethiopian Journal of Environmental Studies & Management, 2017-12-13) Ogendi, G.M.; Moturi, W.M.; Kibitok, N.K.
Surface water is progressively subjected to stress as a result of anthropogenic activities. Systematic observation and characterization of anthropogenic activities along Molo River was done in 2014 to evaluate their effects on surface water quality. Portable GPS receiver was used to identify geographic locations of 23 sites purposively selected; based on their relative positions to the point of anthropogenic activities and included a reference located in the upper reaches. An observation schedule was used to collect data during dry and rainy-season. Chemical parameters were determined by spectrophotometry using standard methods and physical parameters measured in-situ using Wisenschafflich-Technische Werkstätten and pen type Dist 3 Model Meter probes. Data were analyzed using descriptive and inferential statistics. The frequency of occurrence and percentages were computed. Analysis of variance (ANOVA) was used to analyze mean concentrations of various physical-chemical parameters and various sampling occasions. Maximum NO2 was (45.42±3.4 mg∙L−1), NO3 (44.1±0.1 mg∙L−1), SRP 50.25±0.4, DO2 was 0.3±0.0 mg∙L−1, conductivity (616±1.4 μS/cm), and TDS 405.8±8.1 mg∙L−1 while NH4-N 79.69±1.2 mg∙L−1, TN 109.36±09 mg∙L−1, pH was 12.525±8.0 and T ºC 21.4±0.2 ºC. Mean TP was 13.21±1.78 mgL-1 and 2.43±1.70 mgL-1 highly significant at p<0.05 i.e. p= 0.0001. Results indicate that there were significant differences in the means of NO2-N, NO3-N, NH4-N, TN, DO, EC, T°C, and TDS (p=0.0038, 0.0001, 0.0001, 0.0001, 0.0001, 0.0001, 0.0021, and 0.0001) respectively. Observed activities comprised urban-construction/dumping of waste adjacent to riparian-buffer-zones recording 18.4%, domestic animals watered at the river 28.09%, people crossing river using vehicle/motorbikes and/or on-foot 39.2%, children playing in the river 12.9%,water abstraction 11.9%, sand harvesting/quarrying 0.16%, septic tanks-leaks, waste discharged into the river 4% and Washing linen 4.4%.. Washing vehicle/cars/motorbike was highest at the site denoted M3, recording 265 observations. Frequency and intensity of human activities closely relate the results on physical-chemical parameters, interference from direct human activity than natural phenomenon explains the finding. The river water is unsuitable for human consumption.
Characterization of Egerton University wastewater stabilization ponds and assessment of substrate size efficiency in reduction of faecal pollutants in a constructed wetland mesocosm
(Egerton University, 2018-04) Lukhabi, Dorothy Khasisi
The aim of this study was to determine variations in concentration of Pathogen Indicator Organisms (PIOs) namely total coliforms Escherichia coli and heterotrophic bacteria; Biochemical Oxygen Demand (BOD) in Egerton University Wastewater Stabilisation Ponds (WSPs) and the effect of substrate sizes on wastewater treatment. Sampling at the WSPs was done on weekly basis for one month from mid-Nov to mid-Dec 2017 using standard procedures for examination of water and wastewater. A mesocosm study imitating a vertical sub surface flow constructed wetland was conducted to determine the most efficient substrate size in removal of these pollutant indicators. Total coliforms (TC) and E. coli were isolated using selective and differential media following membrane filtration method Colonies were enumerated on chromocult agar. Heterotrophic bacteria (HPCs) were enumerated using standard pour plate method on plate count agar. Biochemical Oxygen Demand was determined by incubating samples in a cabinet whose room temperature ranged between 20 °C to 25 °C for 5 days. For the mesocosm study, three sets of experiments with different gravel aggregate sizes were set up in triplicates. Wastewater from SMP was introduced and settled for six weeks to enable micro-organisms to establish and stabilize, before collection of water samples for analysis on weekly basis for eight weeks. The highest concentration of both PIOs and BOD was in the inlet, and this reduced along the pathway towards the outlet. Apart from BOD5, there was a significant difference between the influent and effluent in all the parameters (p<0.05). The range for TC, E. coli, HPCs and BOD5 was 5.5 x 106 - 2.9 x 1011, 4.4 x 104 - 1.9 x 1010CFUs / 100 ml, 4.5 x 106 - 5.0 x 109 CFUs / ml and 142.8 - 163.6 mg/l respectively. Removal efficiencies ranged between 99.8-99.9 % (3 log units) for both TC and E. coli in both First Maturation Pond and Second Maturation Pond. Heterotrophic Plate Counts reduced in concentration along the treatment pathway by 2 log units. In the mesocosm study, percentage reduction efficiency for TC for different substrate sizes was recorded as 95.3, 90.4 and 88.8 % for small, medium and large gravel aggregate respectively, while E. coli was recorded as 95.2, 94.3 and 88.4 % and HPCs was 99.8, 99.7 and 99.5 %. Furthermore, removal of organic matter was recorded as 15.9, 9.9 and 8.4 % for BOD5 while TSS was 72.7, 56.6 and 52.4 % for small, medium and large sized gravel aggregates respectively. In conclusion, WSPs at Egerton University performed well in removal of PIOs. Heterotrophic bacteria levels indicated presence of pollution with easily degradable organic matter, while BOD5 levels did not. In addition, none of the substrate sizes employed in mesocosm study performed better than the other in removal of PIOs and organic matter
Characterization of temporal and spatial drought risk events using surface water supply index (SWSI) in a tropical river basin
(MEDCRAVE, 2017-02-16) Wambua, Raphael M; Mutua, Benedict M; Raude, James M
In the present study, temporal and spatial drought-risk events are characterized using a Modified Surface Water Supply Index (SWSI) for upper Tana River basin, located in tropics, Kenya. Forty years (1970-2010) hydro-meteorological data for low, lower middle, middle and high elevations at eight hydro-metric stations was used to characterize spatial and temporal distribution of drought. The spatial drought distribution is obtained via interpolation of hydro-metric stations data using Kriging interpolation technique embedded ArcGIS 10.1 was used. The drought trends were analyzed using a non-parametric Mann-Kendall trend test. The results show that south-eastern parts of the basin are the most drought-prone areas at different drought severities and frequencies. Drought severity classes ranged from 1.69-2.22 to 3.39-4.17 and 2.68-3.21 to 4.37-4.96 in 1970 and 2010 respectively across the river basin. The south-western parts of the basin exhibited highest drought frequency ranging from 10.61 to 13.16 while the north-western areas gave frequency values ranging from 3.74 to 6.29. The findings of the study are applicable in Early Drought Warning Systems, prioritized water resources planning and management.
Composition and design of vegetative filter strips instrumental in improving water quality by mass reduction of suspended sediment, nutrients and Escherichia coli in overland flows in eastern escarpment of Mau Forest, Njoro River Watershed, Kenya
(Springer Link, 2016-06-13) Olilo, Casianes; Onyando, Jack; Moturi, Wilkister; Muia, Wairimu; Roegner, Amber; Ogari, Zachary; Ombui, P.; Shivoga, William
This study assessed the effect of vegetative filter strip (VFS) in removal of suspended sediment (SS), total nitrogen, total phosphorus and Escherichia coli (E. coli) in overland flow to improve receiving water quality standards. Four and half kilograms of cowpat manure was applied to the model pasture 14 m beyond the edge of vegetated filter strip (VFS) comprising 10-m Napier grass draining into 20-m Kikuyu grass (VFS II), 10-m Kikuyu grass draining into 20-m Napier grass (VFS III) and native grass mixture of Couch–Buffel (VFS I-control). Overland flow water samples were collected from the sites at positions 0, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25 and 30 m along the length of VFSs. E. coli removal by Napier grass VFS was on the order of log unit, which provided an important level of protection and reduced surface-flow concentrations of E. coli to below the 200 (CFU 100 mL−1) recommended water quality standards, but not for nutrients and SS. The Napier grass showed highest efficiency (99.6 %), thus outperforming both Kikuyu grass (85.8 %) and Couch–Buffel grasses VFS (67.9 ± 4.2 %) in removing E. coli from overland flow. The low-level efficiency of native Couch–Buffel grasses in reducing E. coli in overland flow was because of preferential flow. Composition and design of VFS was instrumental and could be applied with a high potential of contracting the uncertainty in improving water quality standards through mass reduction of SS, nutrients and E. coli load in watersheds.
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.
Development of a non-linear integrated drought index (NDI) for managing drought and water resources forecasting in the upper Tana river basin-Kenya
(2020) Wambua, Raphael M.
This article uses the non-linear integrated drought index (NDI) for managing drought and water resources forecasting in a tropical river basin. The NDI was formulated using principal component analysis (PCA). The NDI used hydro-meteorological data and forecasted using recursive multi-step neural networks. In this article, drought forecasting and projection is adopted for planning ahead for mitigation and for the adaptation of adverse effects of droughts and food insecurity in the river basin. Results that forecasting ability of NDI model using ANNs decreased with increase in lead time. The formulated NDI as a tool for projecting into the future.
Economic efficiency of water use in the small scale irrigation systems used in vegetables production in Koulikoro and Mopti regions, Mali
(The Society of Agricultural Professionals, 2018-07-27) Abdoulah Mamary, Kane; Langat, Jackson; Lagat, Prof; TEME, Pr; Wamuyu, Samuel; SIJALI, Vincent
Malian households depend, in majority, on rain-fed agriculture for their food production. Overreliance on rain-fed agriculture limits the production output due to unreliable rainfall in the country. To mitigate this, the government has invested in rehabilitation of irrigation schemes to reduce dependence on rainfall. Through appropriate irrigation technologies and improved agronomic management practices agricultural productivity will be increased. This study determines the contribution of different irrigation systems to produce vegetables on household welfare in rural communities. The objective of the study was to contribute to improved livelihood of smallholder farmers in rural areas by use of irrigation systems in vegetables production. Three localities corresponding to two specific climatic regions favorable to vegetable crops production in Mali (Baguineda, Kati, Koulikoro region and Mopti region) was the study area. This study was guided by the production theory. Primary data was collected from 273 farmers selected proportionately from four wards (Fanafiecoura and Tieman, in Koulikoro region and Mopti and Dialango, in Mopti region) using face-to-face interviews. Secondary data from literature reviews was also used. Descriptive statistics and DEA functions were used for analysis. The Statistical Package for Social Scientists (SPSS), Stata and Excel programs were used for analysis. This study found that the irrigation systems as used in production of the three main crops to be characterized by inefficiency. Drip and sprinkling irrigation systems was relatively more economically efficient as compared with Californian system. The use of drip, sprinkling and Californian irrigation systems lead to greater benefits as compared to costs. The excess benefit (compared to costs) is realized more with drip followed by sprinkling and the third being California irrigation system. This study recommends more training and capacity building to the farmers in the study area with an aim of reducing their levels of inefficiencies in horticultural crop production. Farmers should be supported to adopt the use of drip, sprinkling and Californian irrigation systems which lead to greater benefits as compared to costs. Drip, sprinkling and Californian irrigation systems present a good opportunity for superior technical efficiency in vegetable production. These irrigation technologies should be promoted.
Effect of net mesh size, exposure duration and net positioning on macro invertebrate drift densities in the Njoro River, Kenya
(Egerton University, 2018-03) Mureithi, Priscilla Wangari; Otuoma, Sanya
Macroinvertebrate drift is a phenomenon that has fascinated and occupied ecologists for a longtime and has produced varied results. Drift samples were collected in a riffle and pool biotopes in the Njoro River between 3rd January and 28th March 2017 with a sole objective of determining whether drift net mesh size, positioning and variation in exposure time could have significant influence on drift densities. Purposive systematic random sampling was employed to collect samples using six nets of 100 ìm, 250 ìm and 500 ìm mesh sizes for three consequent days always alternating the nets at the right, middle and left banks respectively, during seven sampling occasions. The nets were emptied at intervals of 5, 10, 15, 20, 25 and 120 minutes. Benthic samples were also collected during each sampling for quantification of the proportions of benthos that drifted. The mean drift densities (pooled data) between the pool (20.73 ± 0.10 ind.m-3) and riffle (38.79 ± 5.15 ind.m-3) was statistically significant (t-value = 2.821, d.f = 754, P < 0.05). The difference in drift densities among the 100 ìm, 250 ìm and 500 ìm nets was very highly significant (P < 0.001). The 500 ìm net collected the lowest drift densities, followed by the 250 ìm net Tukey’s Honestly Significance Difference (HDS) test, (P < 0.001). Drift densities decreased significantly with increase in exposure time in all the three nets in both biotopes (P < 0.001). Drift densities differed significantly with the net positions at the riffle (One – way ANOVA, F (2,375) = 11.43, P < 0.001) with the left bank having significantly higher densities than the mid-stream and the right bank. One – way ANOVA indicated insignificant difference in mean drift densities among the three positions in the pool (F (2,375) = 0.839, P > 0.05). There was no significant interaction observed among drift net mesh size, drift net position and exposure time in the riffle (Three way- ANOVA, F(20,324) = 0.375, P > 0.05) and pool (Three way- ANOVA, F(20,324) = 0.374, P > 0.05) biotopes. Mean proportion of benthos differed significantly between the riffle and pool biotopes (t = -9.473, d.f = 106, P < 0.001) with the pool having higher proportions than the riffle. This study demonstrates that drift net mesh size, position and exposure time should be taken into account when characterizing invertebrate drift in streams. Maximum drift densities can be obtained by sampling for 5 minutes irrespective of the mesh size used. Future drift studies should consider reduction of sampling time below five minutes as this was omitted in this study. Future studies should also consider drift sampling as a standard complementary tool to benthic sampling in bioassessment protocols of tropical streams.
Effect of water quality on the parasite assemblages infecting Nile tilapia in selected fish farms in Nakuru County, Kenya
(Springer Nature, 2018-08-03) Ojwala, Renis Auma; Otachi, Elick Onyango; Kitaka, Nzula Kivuva
Aquaculture has been documented as the fastest developing food industry in Kenya with increased production since the Government initiated the Economic Stimulus Programme (ESP) in 2009. However, the production has not yet reached the maximum level (20,000 metric tons per year) anticipated in the country. This is due to a number of challenges, top of which is poor water quality resulting from the uncontrolled addition of inputs (fish feeds, inorganic fertilizers, and organic fertilizers) into the ponds. These deteriorate water quality, cause increased incidences of parasite infections, and impede fish production. Therefore, this study investigated the effect of water quality on parasite assemblages infecting Oreochromis niloticus (Linnaeus 1758) in selected fish farms within Nakuru County from November 2016 to February 2017. Selected physico-chemical parameters namely: dissolved oxygen, temperature, pH, conductivity, and turbidity were measured in situ using appropriate meters. Water samples from each fish farm were analyzed for nutrient concentrations using standard methods. A total of 300 fish were examined for parasites. Parasites were counted, preserved, and identified using identification keys and parasitological parameters determined. The results indicated that certain water quality parameters, such as dissolved oxygen, were significantly different for all the six fish farms (one-way ANOVA, p < 0.05). A total of 15 species of parasites were recovered. Trichodina sp. and Cichlidogyrus halli were found in all the studied fish farms. Correspondence analysis revealed that some parasites’ occurrences were highly correlated (positively) with certain water quality parameters. Therefore, regular monitoring and control of water quality in fish ponds are recommended to reduce levels of parasite infestations.
Effects of Population Growth on Urban Extent and Supply of Water and Sanitation: Case of Nakuru Municipality, Kenya
(Journal of Environmental Management, 2019) Muoria, Elizabeth; Moturi, Wilkister; Eshiamwata, George
Urbanization causes changes in social and environmental conditions with most of these changes impacting on the efficient provision of essential services such as water and sanitation. Nakuru Municipality was observed to be the fastest growing urban area in East and Central Africa. Research on patterns and trends of urban and population increase and their implication on water service provision and sanitation in urban Nakuru is very scanty. This paper presents findings from an assessment of the effects of population growth between 1999 and 2017 on urban extent and supply of water and sewage reticulation in Nakuru municipality and surrounding peri-urban areas. Data was collected through remote sensing and administration of questionnaires to urban Nakuru residents and key informants from NAWASSCO respectively to elicit information on the water supply network and sewerage reticulation in Nakuru municipality for the period 1989-2014. Geographic Information System (GIS) was used to analyze the data on time series. The results indicate that the population of Nakuru municipality and surrounding peri-urban areas has increased by 56.8% whereas that of built-up area has increased by 182.5% in the same period through densification of the urban core and expansion to the peri-urban areas characterized by urban sprawl. The water supply network and sewerage reticulation increased by 236km and 89km respectively within Nakuru municipality. The analysis of the maps shows that water supply network and sewerage reticulation are concentrated in the area around the urban core with very little spread. This means that the residents on the outskirts of Nakuru Municipality are not well served by the water supply network and sewerage reticulation. The study recommends involvement of all stakeholders in urban planning and in the water sector in order to increase water supply network and sewerage reticulation coverage both in the urban and peri-urban areas.
Effects of Population Growth on Urban Extent and Supply of Water and Sanitation: Case of Nakuru Municipality, Kenya
(Macrothink institute, 2018-01-08) Muoria, Elizabeth W.; Moturi, Wilkister N.; Eshiamwata, George W.
Urbanization causes changes in social and environmental conditions with most of these changes impacting on the efficient provision of essential services such as water and sanitation. Nakuru Municipality was observed to be the fastest growing urban area in East and Central Africa. Research on patterns and trends of urban and population increase and their implication on water service provision and sanitation in urban Nakuru is very scanty. This paper presents findings from an assessment of the effects of population growth between 1999 and 2017 on urban extent and supply of water and sewage reticulation in Nakuru municipality and surrounding peri-urban areas. Data was collected through remote sensing and administration of questionnaires to urban Nakuru residents and key informants from NAWASSCO respectively to elicit information on the water supply network and sewerage reticulation in Nakuru municipality for the period 1989-2014. Geographic Information System (GIS) was used to analyze the data on time series. The results indicate that the population of Nakuru municipality and surrounding peri-urban areas has increased by 56.8% whereas that of built-up area has increased by 182.5% in the same period through densification of the urban core and expansion to the peri-urban areas characterized by urban sprawl. The water supply network and sewerage reticulation increased by 236km and 89km respectively within Nakuru municipality. The analysis of the maps shows that water supply network and sewerage reticulation are concentrated in the area around the urban core with very little spread. This means that the residents on the outskirts of Nakuru Municipality are not well served by the water supply network and sewerage reticulation. The study recommends involvement of all stakeholders in urban planning and in the water sector in order to increase water supply network and sewerage reticulation coverage both in the urban and peri-urban areas.

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