Philip M Nyenje

Philip M Nyenje
Makerere University · Department of Civil and Environmental Engineering

BSc, MSc, PhD

About

31
Publications
50,110
Reads
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950
Citations
Citations since 2016
19 Research Items
752 Citations
2016201720182019202020212022050100150
2016201720182019202020212022050100150
2016201720182019202020212022050100150
2016201720182019202020212022050100150
Additional affiliations
August 2015 - August 2016
Makerere University
Position
  • Researcher
January 2009 - September 2014
IHE Delft Institute for Water Education
Position
  • PhD research fellow

Publications

Publications (31)
Article
Full-text available
Weathered basement aquifers are vital sources of drinking water in Africa. In order to better understand their role in the urban water balance, in a weathered basement aquifer in Kampala, Uganda, this study installed a transect of monitoring piezometers, carried out spring flow and high-frequency groundwater level monitoring, slug tests and hydroch...
Article
This study investigated the influence of on-site sanitation practices (OSS) on antibiotics in shallow groundwater underlying an informal settlement in Kampala City (Uganda) and the resulting antibiotic resistance risks. Ten antibiotics (including sulfonamides, fluoroquinolones, quinolones, penicillins and tetracyclines) were investigated in 17 grou...
Article
Full-text available
We mapped the double-stranded DNA (dsDNA) virus assemblage in groundwater below sub-Saharan urban poor settlements in Arusha (Tanzania), Dodowa (Ghana), and Kampala (Uganda). Our results indicated that ∼80% of dsDNA virus sequences matched the order of Caudovirales, i.e., indigenous bacteriophages; 1.8% of the dsDNA virus sequences matched those of...
Article
Full-text available
Socio-institutional factors are poorly addressed in the risk assessment of groundwater contamination. This paper contributes to the development of a socio-institutional assessment framework based on a case study of contamination by on-site sanitation (OSS) in an informal settlement of Bwaise (Kampala, Uganda). We conducted a snapshot survey of the...
Article
Full-text available
This study investigated the occurrence and seasonal variation in concentrations of emerging organic contaminants (EOCs) in shallow groundwater underlying two peri-urban areas of Bwaise (highly urbanised) and Wobulenzi (moderately urbanised) in Uganda. Twenty-six antibiotics, 20 hydrocarbons, including 16 polycyclic aromatic hydrocarbons (PAHs), and...
Article
The development of and access to freshwater resources in East Africa is fundamental to the region's sustainable development goals. Following vision documents for regional development and working with local stakeholders, we developed water scenarios up to 2050 that inform the hydro-economic modeling analysis of the extended Lake Victoria Basin, the...
Article
Full-text available
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Article
This paper empirically investigates the implementation of Supplier Alliances in the public sector in developing countries using a case study of Uganda. Data were collected from experienced procurement practitioners in Uganda. Seventy-nine respondents participated in the study. Questionnaires and interview guides were administered to collect quanti...
Article
Full-text available
High urbanization in Sub-Saharan Africa (SSA) has resulted in increased peri-urban groundwater contamination by on-site sanitation. The World Health Organization introduced Water Safety Plans (WSP) towards the elimination of contamination risks to water supply systems; however, their application to peri-urban groundwater sources has been limited. F...
Article
Full-text available
The development of and access to freshwater resources is fundamental if East Africa aims to achieve its goal of increased economic growth. Following vision documents for regional development and working together with local stakeholders, we developed water scenarios up to 2050 that inform the hydro-economic modelling analysis for the extended Lake V...
Article
Full-text available
Groundwater in sub-Saharan Africa supports livelihoods and poverty alleviation1,2, maintains vital ecosystems, and strongly influences terrestrial water and energy budgets³. Yet the hydrological processes that govern groundwater recharge and sustainability—and their sensitivity to climatic variability—are poorly constrained4,5. Given the absence of...
Article
Full-text available
This paper explores how transition management processes can be designed to address the unsustainability of water, sanitation, and hygiene (WASH) services in informal settlements in cities in Sub-Saharan Africa. The unsustainability of services related to WASH in informal settlements in Sub-Saharan Africa is deeply embedded in current societal and g...
Preprint
Full-text available
The unsustainability of the services related to water, sanitation and hygiene in informal settlements in Sub-Saharan Africa services is deeply embedded in current societal and governance structures, cultures and practices; it is context-dependent and involves numerous actors with different interests. The field of sustainability transitions research...
Article
Decentralised faecal sludge (FS) dewatering in urban slums using centrifugation technology has potential to reduce public health risks and environmental pollution caused by indiscriminate disposal of untreated FS. A laboratory-scale centrifuge was applied to dewater FS from lined pit latrines, conditioned with sawdust and charcoal dust. Response su...
Article
Faecal sludge (FS) treatment in urban slums of low-income countries of sub-Saharan Africa is poor or non-existent. FS contains over 90% water and therefore, dewatering it within slums decreases transport costs, facilitates local treatment and end-use. This study was designed to enhance the dewatering efficiency of FS, using two locally available ph...
Article
There is increasing interest to improve the functionality and performance of pit latrines in low income urban areas. This study aimed at assessing the ambient and pit environmental conditions and their implications on the performance (smell and fly nuisance) of pit latrines. Forty-two pit latrines were investigated in urban slums of Kampala, Uganda...
Article
The current practices of faecal sludge management in urban slums pose risks to public health and environmental pollution. Given that faecal sludge contains high water content, dewatering it presents an important step of managing it effectively. This paper therefore explores the applicability of dewatering as the first step in decentralized treatmen...
Article
Full-text available
Large scale application of biogas latrine technology in developing countries faces technical, socioeconomic and financial challenges. As a result, harnessing its full potential has not been realized. This study examined variables describing the design, construction, operation and maintenance of nineteen biogas latrines in relation to their performa...
Article
Full-text available
BackgroundA pit latrine is the most basic form of improved sanitation which is currently used by a number of people around the globe. In spite of the wide spread use, known successes and advantages associated with pit latrines, they have received little attention in form of research and development. This review focuses on the usage and performance...
Article
In many urban poor areas of Sub-Saharan Africa (SSA), demand for human excreta disposal is met, predominantly by pit latrines. This study aimed at determining the status of pit latrines (design, construction, operation and maintenance) and its influence on latrine performance (filling, smell and insect nuisance). The study was conducted on 130 pit...
Article
We applied graphical methods and multivariate statistics to understand impacts of an unsewered slum catchment on nutrients and hydrochemistry of groundwater in Kampala, Uganda. Data were collected from 56 springs (groundwater), 22 surface water sites and 13 rain samples. Groundwater was acidic and dominated by Na, Cl and NO3. These ions were strong...
Article
Full-text available
Urban catchments in sub-Saharan Africa (SSA) are increasingly becoming a major source of phosphorus (P) to downstream ecosystems. This is primarily due to large inputs of untreated wastewater to urban drainage channels, especially in informal settlements (or slums). However, the processes governing the fate of P in these catchments are largely unkn...
Article
Full-text available
The transport of excessive phosphorus (P) discharged from unsewered informal settlements (slums) due to poor on-site sanitation is largely unknown. Hence, we investigated the processes governing P transport in a 28 km2 slum-dominated catchment in Kampala, Uganda. During high runoff events and a period of base flow, we collected hourly water samples...
Article
The burgeoning of slums in the developing world poses an urgent environmental threat due to insanitary conditions and rampant disposal of wastewater. To assess the potential environmental impacts, domestic wastewater from Ghana's biggest urban slum - Old Fadama was characterised throughout the dry and wet seasons. The study drew on a comprehensive...
Article
Access to potable water and basic sanitation in urban poor communities remains a critical issue in the developing world. This paper examines access to potable water and basic sanitation in Ghana's largest urban slum and the level of commitment by stakeholders to improve the current conditions. It drew on an extensive field survey, interviews, focus...
Article
Full-text available
Groundwater in unsewered urban areas is heavily contaminated by onsite sanitation activities and is believed to be an important source of nutrients ex-filtrating into streams and thus contributing to eutrophication of Lakes in urban areas. Currently the fate of nutrients and especially phosphorus leached into groundwater in such areas is not well k...
Article
Eutrophication is an increasing problem in sub-Saharan Africa (SSA), and, as a result, the ecological integrity of surface waters becomes compromised, fish populations become extinct, toxic cyanobacteria blooms are abundant, and oxygen levels reduce. In this review we establish the relationship between eutrophication of fresh inland surface waters...
Article
The effects of climate change on groundwater recharge and baseflow in the upper Ssezibwa catchment, Uganda, are investigated. The study first examines historical data, which indeed reveal evidence of climate change based on trends observed in temperature and discharge. For the climate change study, the statistical downscaling model (SDSM) is used t...
Article
This study investigates the potential effects of climate change on the hydrology of Ssezibwa catchment in Uganda. The study employs statistical downscaling techniques, which have of recent proved useful in deriving more detailed and reliable climate change scenarios for use in hydrological models for impact assessment. The first part of this study...

Questions

Questions (6)
Question
Given a set of values of a variable x= 40, 25, 20, 15, 12, and 5:
The probability of exceedance of a value x=20 written as  P (x>=20)  can be got by arranging data is descending order thus giving a value of 0.5
The probability of non-exceedance of a value x=20 written as  P (x<=20) and can be got by arranging data is ascending order thus giving a value of 0.67
On checking P(x>=1) = 1 - P(x<=1) gives
0.5 = 1 - 0.67 which is not correct. Is this error creating by the estimations made using the probability formulae?
Question
I notice that when I use the SCS curve number method using annual rainfall amounts, I get much more runoff than when using daily or monthly runoff. How can this be explained? Is the SCS curve number suited for daily runoff and not annual rainfall estimates?
Example: A catchment with a curve number of 75 gives an S value of 84.6mm. For month rainfalls of 50.9, 66, 140.3, 223.7, 105.8, 68.2, 79.2, 201.9, 118.5, 47.9, 63.7 and 5.8mm, I get accumulated runoff of 546 mm.
If I use the total annual rainfall, which amounts to 1171.9mm, the corresponding runoff will be 1076.1mm. How can this be explained?
Question
I want to estimate the discharge at the outlet of an ungauged catchment in order to determine how much water is available for water supply. The only runoff data I have is that of a much larger catchment. My ungauged catchment is also located in this larger catchment. How can I use a hydrological model like SWAT to simulate the runoff in the ungauged catchment using the runoff data of the gauged catchment? 
Question
Sometimes I get confused as to the source of HCO3 in non calcareous aquifers. In most literature, they say it is derived when CO2 dissolves in water. This then forms HCO3 which is a pH buffer. Hence groundwater with high HCO3 concentrations has a relatively high pH
CO2 + H20 <----> H2CO3 <-------> HCO3 + H+
But in some literature it is also stated that when CO2 mixes with water, it forms carbonic acid which decreases the pH of groundwater.
Is the CO2 dissolving in water responsible for the creation of both carbonic acid and bi-carbonate or bicarbonate is derived form another source?
Question
I want to perform principal components analysis (PCA) and cluster analysis (HCA) on a hydrochemical dataset using SPSS or R. But it is a requirement that data has to be normally distributed before these analyses are done. How is normal distribution of the data accounted for when performing PCA or HCA using R or SPSS.
In R, there is a provision to scale the data either using median and variance or the mean and variance (see an example below). Is this the same as normalising data?
An example of scaling data in R:
> medians<-apply(data,2,median)
> mads<-apply(snapshot.use,2,mad)
data_ok-< scale(data,center=medians,scale=mads)

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Projects

Projects (5)
Project
Slums are increasing in urban communities in developing countries. It is often difficult or impossible to relocate such communities, although their impact on the environment may be extremely negative. The study looked at the impact of such unsewered communities on water resources on such communities.