Faculty of Engineering, Design and Technology

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Access to improved sanitation facilities in low-income informal settlements of East African cities
(2015-03-05) Okurut, Kenan; Kulabako, R. N.; Adogo, J. M.; Chenoweth, J.; Pedley, S.; Tsinda, A.; Charles, K.
Throughout Africa, the population in urban areas is increasing rapidly beyond the capacity and the resources of the cities to accommodate the people. In Sub-Saharan Africa, the majority of urban dwellers live in informal settlements served by inadequate sanitation facilities. These areas present unique challenges to the provision of sanitation, and there is inadequate information on access to improved facilities. This paper reports findings of a study undertaken in low-income informal settlements using mixed methods to assess access to sanitation and identify the barriers to household improved sanitation facilities. Although more than half (59.7%) of the respondents reported using sanitation facilities that are included in the JMP definition of improved sanitation, a high proportion of these facilities did not provide “ access to basic sanitation” and less than 5% of all the respondents did not report issues related to sustainable access to basic sanitation. The findings highlight the urgent need to develop a more specific and strategic interventions for each low-income informal settlement, to upscale the sustainable access and use of improved sanitation in urban centres.
Amplifying Local Voices to Reduce Failure in the Water, Sanitation and Hygiene Sector
(Royal Academy of Engineering, 2021) Barrington, D.J; Sindall, R.C; Chinyama, A; Morse, T; Sule, M.N; Beale, J; Kativhu, T; Krishnan, S; Luwe, K; Malolo, R.D; Mcharo, O; Odili, A; Ravndal, K.T; Rose, J; Shaylor, E; Wozei, Eleanor
WASH endeavours regularly fail. Sometimes this means that entire programmes do not achieve their stated aims, sometimes these failures are setbacks which can be rectified with sufficient reflection and action. This research aimed to develop an evidence base of how and why field-based WASH professionals in four sub-Saharan African countries believe failures occur, their experiences when sharing and discussing them within their organisations, and how they believe a culture conducive to publicly sharing and learning from failures could be nurtured.
Analysis of persistence soil nutrient status in abandoned cattle kraals in a semi arid area in Botswana
(2010-12) Kizza, Sarah; Otlogetswe, Totolo; Perkins, Jeremy; Olusegun, Areola
The aim of this study was to analyze the depletion of soil nutrients with time on abandoned kraals in a peri-urban area of Botswana. Active kraals are enriched with nutrients through the accumulation of animal droppings and this study was aimed at assessing how long the impact of this soil nutrient enrichment persists after kraal abandonment. A total of 25 disused kraals, that had been abandoned for periods ranging from 1 to 45 years were sampled. The soil parameters analyzed included particle size distribution (%), bulk density (g/cm3), pore space (%), moisture content (%), pH in water and KCl solution, EC (µS/cm), organic matter (%), CEC (meq/100g), exchangeable Ca++ (cmolc/kg), Mg++ (cmolc/kg),K+ (cmolc/kg), Na+ (cmolc/kg), nitrogen [NH4-N (mg/kg), NO3-N (mg/kg), TKN (%), and Olsen P (mg/kg). Results showed that soil nutrient concentrations on abandoned kraals generally were significantly higher than at the control sites. Soil nutrient concentrations decreased with time as abandoned kraals retrogressed towards their pre-kraal conditions. However, the effects of soil nutrient enrichment from animal wastes persist long after kraal abandonment. For example, soil Olsen P, Ca++ and Mg++ levels in kraal sites that had been abandoned for over 45 years were still significantly higher than in the control sites. In a pastoral system such as is practiced in Botswana where kraal manure is not used as soil amendment, the whole ecosystem suffers as soil nutrients are transferred and concentrated at isolated spots (kraals).
Analysis of the Accuracy of GMF, NMF, and VMF1 Mapping Functions with GPT 50 a Priori Zenith Constraint in Tropospheric Delay Modelling
(2015-01) Makabayi, Brian; Hunegnaw, Addisu
When modelling the tropospheric delay in Global Positioning System (GPS), the zenith delay is mapped to the slant with numerous mapping functions. The accuracy of the modelled tropospheric delay will be affected by the kind of mapping function used. Fixing the a priori zenith constraint as Global Temperature Pressure Humidity 50 (GPT 50), this paper compares the accuracy of the different mapping. Global Mapping Function (GMF), Niell Mapping Function (NMF) and Updated Vienna Mapping Function (VMF1), the update of Vienna Mapping Function (VMF) are the mapping functions studied. All these are used with the saastamoinen tropospheric delay model which is used in the GPS Analysis Software for the Massachusetts Institute of Technology software (GAMIT_GLOBK). For the north and east offsets these mapping functions achieved the same accuracy and can therefore be used interchangeably in modelling of the tropospheric delay effect in the planner. However, for the up offsets VMF1 achieved better accuracy compared to GMF and NMF however, being more consistent with GMF than NMF. In the future, if more mapping functions are incorporated in GAMIT_GLOBK, the accuracy of these new mapping functions should be investigated and use another a priori zenith constraint – meteorological data, which will improve positioning using Global Navigation Satellite System (GNSS).
Application of a yeast-based assay protocol developed to monitor total oestrogenic activity induced by 17β-oestradiol in activated sludge supernatants from batch experiments
(Lawrence Berkeley National Laboratory, 2006-04-11) Wozei, Eleanor; Hermanowicz, SW
Batch experiments were carried out with activated sludge from laboratory reactors and a full-scale treatment plant spiked with 17β-oestradiol (E2). An oestrogen-sensitive yeast-based assay protocol, described in detail in a related publication, was used to measure reduction of E2-induced total oestrogenic activity from the sludge supernatant over a 15 d period after which the sludge was re-spiked to check for possible enhancement of reduction by pre-exposed sludge during an additional 15 d period. The reduction was generally improved by increasing sludge solids concentrations and by continuous mixing. For a 100 ngE2/ℓ spike there was >40% reduction of oestrogenic activity within 15 d, which improved to >70% by pre-exposing the sludge. The oestrogenic activity produced by a dose of 100 μgE2/ℓ was readily removed by most sludges within 15 d. How¬ever, re-spiking the activated sludge with the same E2 concentration caused some sludges to lose reduction capacity.
Assessing demand for improved sustainable sanitation in low-income informal settlements of urban areas: a critical review
(2014-03-13) Okurut, Kenan; Kulabako, Robinah Nakawunde; Chenoweth, Jonathan; Charles, Katrina
Sanitation improvement is crucial in saving lives that are lost due to water contamination. Progress towards achieving full sanitation coverage is still slow in low-income informal settlements in most developing countries. Furthermore, resources are being wasted on installing facilities that are later misused or never used because they do not meet the local demand. Understanding demand for improved sanitation in the local context is critical if facilities are to be continually used. Various approaches that attempt to change peoples’ behaviours or create demand have been reviewed to identify what they are designed to address. A multi-disciplinary research team using mixed methods is re-emphasised as a comprehensive approach for assessing demand for improved sanitation in low-income informal settlements, where the sanitation situation is more challenging than in other areas. Further research involving a multi-disciplinary research team and use of mixed methods to assess sanitation demand in informal settlements is needed.
Assessment of apparent losses in urban water systems
(2011-08-17) Mutikanga, Harrison E.; Sharma, Saroj K.; Vairavamoorthy, Kalanithy
Apparent losses relate to water that is consumed but not paid for. Most research carried out in the last decade particularly in the United Kingdom focused mainly on leakage. Until now, there are no set procedures and guidelines for assessment of apparent losses. Much work remains to bring it to par with the available tools and methodologies for leakage management. In the absence of adequate data and proper methodology, most developed countries use default values, which tend to be lowest values for well-managed water systems, for computation of apparent losses. These may not be appropriate for developing countries. This paper presents a methodology for the assessment of different components of apparent losses based on field audit and operational data for Kampala city’s water distribution system in Uganda. Metering inaccuracies and illegal use have been found to be significant components of apparent losses. Appropriate intervention strategies have been developed based on the assessment.
Assessment of Physical Conditions and Proposed Best Management Practices of Domestic Storage Tanks Supplied by a Water Utility in a Rapidly Growing City
(International Formulae Group Journal, 2021) Wozei, E.; Makoko, E.W.
The physical conditions of domestic storage tanks for customers supplied by a water utility were assessed in Kampala, a rapidly growing City in Uganda. A longitudinal assessment of 372 storage tanks in 6 sampled administrative Wards with a minimum of 6 samples collected from each site in both wet (March-May) and dry (June-August) months of 2017 was carried out. A set of guiding questions were used to establish tank conditions with a YES or NO response and a range of low to critical risk rating. It was revealed that there was a statistically significant relationship (p=0.001) between tank physical conditions and quality of stored water. Two of six Wards in the City had high levels of water contamination related to domestic water storage tanks with poor sanitary conditions and contaminated water with E. coli. The study therefore revealed that the physical conditions and management of domestic water storage tanks have an effect on water quality. This is important information for a water utility as it means that it is not enough to supply safe water if the quality may deteriorate upon storage at the consumer premises. A routine inspection checklist and consumer guidelines for domestic storage tank management are proposed.
Biologically directed environmental monitoring, fate, and transport of estrogenic endocrine disrupting compounds in water: A review
(Elsevier Publications, 2006) Campbell, Chris G.; Borglin, Sharon E.; Green, F. Bailey; Grayson, Allen; Wozei, Eleanor; Stringfellow, William T.
Endocrine disrupting compounds (EDCs) are contaminants that may be hormonally active at low concentrations and are emerging as a major concern for water quality. Estrogenic EDCs (e-EDCs) are a subclass of EDCs that, when organisms are exposed to them, function as estrogens. Given that there are numerous e-EDCs that can negatively affect humans and wildlife, general screening techniques like biologically based assays (BBAs) may provide major advantages by estimating the total estrogenic effects of many e-EDCs in the environment. These techniques may potentially be adapted for field portable biologically directed sampling and analyses. This article summarizes available BBAs used to measure estrogenic e-EDCs in the environmental samples and also presents results relating to fate and transport of e-EDCs. Estrogenic EDCs appear to be almost ubiquitous in the environment, despite low solubility and high affinity of organic matter. Potential transport mechanisms may include: (1) transport of more soluble precursors, (2) colloid facilitated transport, (3) enhanced solubility through elevated pH, and (4) the formation of micelles by longer-chain ethoxylates. Due to their persistent and ubiquitous nature, source control strategies for e-EDCs may reduce influent concentration to wastewater treatment plants so that the post treatment effluent will decrease concentrations to estrogenically inactive levels. Alternatively if source reduction is not possible, then more testing is needed on tertiary treatment technologies and treatment efficiencies for e-EDCs. There is still a need for research on remediation and restoration approaches for habitats disturbed by elevated e-EDC concentrations.
Calibrating an optimal condition model for solar water disinfection in peri-urban household water treatment in Kampala, Uganda
(IWA Publishing, 2013) Okurut, Kenan; Wozei, Eleanor; Kulabako, Robinah; Nabasirye, Lillian; Kinobe, Joel
In low income settlements where the quality of drinking water is highly contaminated due to poor hygienic practices at community and household levels, there is need for appropriate, simple, affordable and environmentally sustainable household water treatment technology. Solar water disinfection (SODIS) that utilizes both the thermal and ultra-violet effect of solar radiation to disinfect water can be used to treat small quantities of water at household level to improve its bacteriological quality for drinking purposes. This study investigated the efficacy of the SODIS treatment method in Uganda and determined the optimal condition for effective disinfection. Results of raw water samples from the study area showed deterioration in bacteriological quality of water moved from source to the household; from 3 to 36 cfu/100 mL for tap water and 75 to 126 cfu/100 mL for spring water, using thermotolerant coliforms (TTCs) as indicator microorganisms. SODIS experiments showed over 99.9% inactivation of TTCs in 6 h of exposure, with a threshold temperature of 39.5± 0.7 WC at about 12:00 noon, in the sun during a clear sunny day. A mathematical optimal condition model for effective disinfection has been calibrated to predict the decline of the number of viable microorganisms over time.
A Case for Urban Liveability From Below: Exploring the Politics of Water and Land Access for Greater Liveability in Kampala, Uganda
(Local Environment. The International Journal of Justice and Sustainability. Routledge Taylor and Francis, 2019) Nastar, Maryam; Isoke, Jennifer; Kulabako, Robinah; Silvestri, Giorgia
Improving urban liveability and prosperity is commonly set as a priority in urban development plans and policy around the world. Several annual reports produced by international consulting firms, media, and global agencies rank the liveability of cities based on a set of indicators, to represent the quality of life in these cities. The higher is the ranking, the more liveable is the city. In this paper, we argue that such quantitative approaches to framing and addressing urban liveability challenges leave little room to reflect on people’s experiences of this liveability, which cannot be expressed through numbers. To illustrate our argument, we draw on empirical evidence of urban liveability challenges in access to water and land in Kampala, the capital city of Uganda, ranked recently as the most liveable East African city by various global agencies and media outlets. By showing that increasing the number of water connections does not guarantee improved access to water and sanitation in the long run, first, we demonstrate how urban liveability challenges are tightly linked with land-title issues in the city. Second, we highlight the political game-playing between the central government, the opposition, the traditional leadership, and the slum dwellers in governance processes of service delivery. Finally, by arguing that urban liveability can be enhanced by broadening political participation in city development planning, we discuss some of the strategies that can be used by communities to make collective claims towards improving their quality of life and the environment.
Challenges to Achieving Sustainable Sanitation in Informal Settlements of Kigali, Rwanda
(2013-12-10) Tsinda, Aime; Abbott, Pamela; Pedley, Steve; Charles, Katrina; Adogo, Jane; Okurut, Kenan; Chenoweth, Jonathan
Like most cities in developing countries, Kigali is experiencing rapid urbanisation leading to an increase in the urban population and rapid growth in the size and number of informal settlements. More than 60% of the city’s population resides in these settlements, where they experience inadequate and poor quality urban services including sanitation. This article discusses the issues and constraints related to the provision of sustainable sanitation in the informal settlements in Kigali. Two informal settlements (Gatsata and Kimisagara) were selected for the study, which used a mixed method approach for data collection. The research found that residents experienced multiple problems because of poor sanitation and that the main barrier to improved sanitation was cost. Findings from this study can be used by the city authorities in the planning of effective sanitation intervention strategies for communities in informal settlements.
Characterization of municipal waste in Kampala, Uganda
(2014-02-18) Komakech, Allan J.; Banadda, Noble E.; Kinobe, Joel R.; Kasisira, Levi; Sundberg, Cecilia; Gebresenbet, Girma; Vinnerås, Bjorn
In Kampala, Uganda, about 28,000 tons of waste is collected and delivered to a landfill every month. Kampala Capital City Authority (KCCA) records show that this represents approximately 40% of the waste generated in the city. The remaining uncollected waste is normally dumped in unauthorized sites, causing health and environmental problems. However, the organic fraction of domestic waste can provide an opportunity to improve livelihoods and incomes through fertilizer and energy production. This study characterized the municipal waste generated in Kampala and delivered to Kiteezi landfill between July 2011 and June 2012, that is, covering the dry and wet months. On each sampling day, waste was randomly selected from five trucks, sorted and weighed into different physical fractions. Samples of the organic waste from each truck were analyzed for total solids, major nutrients, and energy content. During the wet months, the waste consisted of 88.5% organics, 3.8% soft plastics, 2.8% hard plastics, 2.2% paper, 0.9% glass, 0.7% textiles and leather, 0.2% metals, and 1.0% others. During the dry months, the waste consisted of 94.8% organics, 2.4% soft plastics, 1.0% hard plastics, 0.7% papers, 0.3% glass, 0.3% textile and leather, 0.1% metals, and 0.3% others. The organic waste on average had a moisture content of 71.1% and contained 1.89% nitrogen, 0.27% phosphorus, and 1.95% potassium. The waste had an average gross energy content of 17.3 MJ/kg. It was concluded that the organic waste generated can be a suitable source of some plant nutrients that are useful especially in urban agriculture. Implications: The result of the waste characterization in Kampala was found to be significantly different from that obtained for other Sub-Saharan African (SSA) cities, showing that studies assuming average values for the waste fractions are likely to result in erroneous results. Furthermore, no reduction in organic fraction of the waste was noticed when compared with a study done two decades ago in spite of greatly improved economic status of Kampala city, a finding that is not in agreement with several other similar studies done for other SSA cities.
Characterizing the Movement Patterns of Minibus Taxis in Kampala’s Paratransit System
(Journal of Transport Geography, 2021) Ndibatya, Innocent; Booysen, M.J.
Urban travelers in Africa depend on minibus taxis for their daily social and business commuting. This paratransit system is loosely regulated, self-organizing, and evolves organically in response to demand. Our study used floating car data to analyze and describe the movement characteristics of nine minibus taxis in Kampala, Uganda. We made three intriguing findings. Firstly, in searching for, picking up and transporting passengers, minibus taxi trajectories followed a heavy-tailed power-law distribution similar to a “L´evy walk”. Secondly, their routes’ topology and shape gradually changed. Thirdly, the extraordinary winding (expressed in terms of tortuosity) of the paths suggested the extreme determination of the drivers’ search for passengers. Our findings could help city planners to build on the self-organizing characteristics of the minibus taxi system, and improve the mobility of travelers, by optimizing routes and the distribution of public amenities.
Communities of Trees Along a Tropical Forest Restoration Gradient
(2016-01) Owiny, Arthur A.
Increasing rates of deforestation in tropical forests have been linked to agriculturalists. A critical concern generating debate is how well communities of trees recover into a more species rich ecosystem after restoration planting. The aim of the study was to evaluate the pattern of recovery of communities of tree, assess the influence of Acanthus pubescens, Lantana camara and Pennisetum purpureum, on the recovery as well as how restoration planting facilitates recruitment of other native tree seedlings along a gradient of forest restoration in Kibale National Park, Uganda after evictions of illegal settlers. We studied six restoration forests ranging in age from 3 to 16 years, naturally regenerating and three primary forests. Our results showed that recovery with natural regeneration was more effective than restoration planting although the latter enhanced recruitment of other native tree seedling. Tree recovery was generally correlated with age so that species density and diversity increased although at different rates. A reverse pattern was found for dominance but no clear pattern was found for tree density (individual/ha). Communities of tree showed directional patterns of change however community composition were still distinct among the different forests. A. pubescens, L. camara and P. purpureum negatively correlated with species density, tree density and diversity but a positive correlation was found for dominance. Restoration planting can reestablish forests with high species density, tree density and diversity, but this is dependent on age and the extent of the herbs, grasses and shrubs cover in tropical forests.
Compound Cis-Regulatory Elements With Both Boundary and Enhancer Sequences in the Human Genome
(Oxford University Press, 2013-10) Jjingo, Daudi; Wang, Jianrong; Conley, Andrew B.; Lunyak, Victoria V.; Jordan, I. King
Motivation: It has been suggested that presumably distinct classes of genomic regulatory elements may actually share common sets of features and mechanisms. However, there has been no genome-wide assessment of the prevalence of this phenomenon. Results: To evaluate this possibility, we performed a bioinformatics screen for the existence of compound regulatory elements in the human genome. We identified numerous such collocated boundary and enhancer elements from human CD4þ T cells. We report evidence that such compound regulatory elements possess unique chromatin features and facilitate cell type-specific functions related to inflammation and immune response in CD4+ T cells.
Computational identification of transposable elements in the mouse genome
(2007) Jjingo, Daudi; Makalowski, Wojciech
Repeat sequences cover about 39 percent of the mouse genome and completion of sequencing of the mouse genome [1] has enabled extensive research on the role of repeat sequences in mammalian genomics. This research covers the identification of Transposable elements (TEs) within the mouse transcriptome, based on available sequence information on mouse cDNAs (complementary DNAs) from GenBank [28]. The transcripts are screened for repeats using RepeatMasker [23], whose results are sieved to retain only Interspersed repeats (IRS). Using various bioinformatics software tools as well as tailor made programming, the research establishes: (i) the absolute location coordinates of the TEs on the transcript. (ii) The location of the IRs with respect to the 5’UTR, CDS and 3’UTR sequence features. (iii) The quality of alignment of the TE’s consensus sequence on the transcripts where they exist, (iv) the frequencies and distributions of the TEs on the cDNAs, (v) descriptions of the types and roles of transcripts containing TEs. This information has been collated and stored in a relational database (MTEDB) at http://warta.bio.psu.edu/htt_doc/M TEDB/homepage.htm).
Design of an Improved Cooking Stove Using High Density Heated Rocks and Heat Retaining Techniques
(Journal of Renewable Energy-Hindawi, 2018) Bantu, Anthony A.; Nuwagaba, Gilbert; Kizza, Sarah; Turinayo, Yonah K.
In sub-Saharan Africa, dependence on wood fuel has caused significant depletion of vegetative resources. Whereas there exist hundreds of improved cooking stoves, many have not reached their maximum potential because their designs are predominantly focused on either fuel efficiency or reduced smoke. This research designed and fabricated an improved charcoal stove using high density rocks and heat retaining techniques.The aim was to retain heat and minimise heat losses in cooking devices with a sole purpose of reducing the amount of fuel used during cooking. The stove design herein incorporates the interaction of physical and thermal properties of granite rocks with heat loss theories to give a thermal efficient unit. The stove was estimated to cost US$ 36 which compared favourably with most of the improved charcoal stoves on international market (US$ 3–50 US$). This study revealed that, by introducing the new stove design and insulation, the granite rocks depicted high thermal storage properties with potential for reducing fuel use by over 78% with reference to the open fire stove.The designed granite rock stove therefore paves way for the use of high density rocks in improved cook stoves to achieve high performance energy efficient systems that can sustainably put to use vegetative resources.
Detecting estrogenic activity in water samples with estrogen-sensitive yeast cells using spectrophotometry and fluorescence microscopy
(2006-03) Wozei, Eleanor; Holman, H-Y.N.; Hermanowicz, S.W.; Borglin, S.
Environmental estrogens are environmental contaminants that can mimic the biological activities of the female hormone estrogen in the endocrine system, i.e. they act as endocrine disrupters. Several substances are reported to have estrogen-like activity or estrogenic activity. These include steroid hormones, synthetic estrogens (xenoestrogens), environmental pollutants and phytoestrogens (plant estrogens). Using the chromogenic substrate ortho-nitrophenyl-β-D-galactopyranoside (ONPG) we show that an estrogen-sensitive yeast strain RMY/ER-ERE, with human estrogen receptor (hERα) gene and the lacZ gene which encodes the enzyme β-galactosidase, is able to detect estrogenic activity in water samples over a wide range of spiked concentrations of the hormonal estrogen 17β-estradiol (E2). Ortho-nitrophenol (ONP), the yellow product of this assay can be detected using spectrophotometry but requires cell lysis to release the enzyme and allow product formation. We improved this aspect in a fluorogenic assay by using fluorescein di-β-D galactopyranoside (FDG) as a substrate. The product was visualized using fluorescence microscopy without the need to kill, fix or lyse the cells. We show that in live yeast cells, the uptake of E2 and the subsequent production of β-galactosidase enzyme occur quite rapidly, with maximum enzyme-catalyzed fluorescent product formation evident after about 30 minutes of exposure to E2. The fluorogenic assay was applied to a selection of estrogenic compounds and the Synchrotron-based Fourier transform infrared (SR-FTIR) spectra of the cells obtained to better understand the yeast whole cell response to the compounds. The fluorogenic assay is most sensitive to E2, but the SR-FTIR spectra suggest that the cells respond to all the estrogenic compounds tested even when no fluorescent response was detected. These findings are promising and may shorten the duration of environmental water screening and monitoring regimes using yeast-based estrogen assays, and the development of biosensors for environmental estrogens designed to complement quantification methods.
Developing a yeast-based assay protocol to monitor total oestrogenic activity induced by 17β-oestradiol in activated sludge supernatants from batch experiments
(Lawrence Berkeley National Laboratory, 2006-04-11) Wozei, Eleanor; Hermanowicz, SW
A yeast-based assay protocol developed for detecting oestrogenic activity in activated sludge (AS) supernatant is described. The protocol used Saccharomyces cerevisiae construct RMY/ER-ERE with human oestrogen receptor (ERα) and lacZ reporter genes, and was developed by modifying existing assays for use with AS samples from batch experiments. The method was able to detect total oestrogenic activity (without prior extraction) in supernatants of AS spiked with 17β-oestra¬diol (E2) with a detection limit of 0.03 ngE2-equivalent/ℓ and an overall quantification limit of 100 ngE2-equivalent/ℓ. Mean E2-induced oestrogenic activity recoveries of >56% were obtained from the spiked samples.

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