Department of Civil and Environmental Engineering

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An assessment of the impact of construction activities on the environment in Uganda: a case Study of Iganga Municipality
(Journal of Construction Engineering and Project Management., 2012-11-15) Muhwezi, Lawrence; Kiberu, Faisal; Kyakula, Michael; Batambuze, Alex O.
Construction while being an economic activity that provides facilities and infrastructure, it is beneficial to man in some aspects and detrimental in others. There have been environmental concerns related to construction activities globally which mainly focus on atmospheric emissions, depletion of natural resources and energy issues. This study was carried out to assess the impacts of construction activities on the environment in Iganga Municipality and to propose measures for their mitigation. The methodology included: review of relevant literature, observations of the general environmental effects of construction activities, focus groups and a survey conducted among construction industry role players to determine their perceptions and opinions regarding environmental impact of construction activities. The collected data was presented in tabular form and analysed by description of responses to questions. The study revealed that forests were the most greatly degraded due to high demand of timber for construction followed by wetlands degradation. The findings of this study will be useful to architects, designers and builders in order to carefully design buildings and other infrastructure that are environmentally friendly and sustainable. Construction materials and their mode of acquisition are harmful threats to the environment. There is need to reduce the consumption of these materials through recycling and reusing wastes to reduce on waste generation, use of virgin materials and the subsequent waste of energy used in new material production.
Occupational safety training and practices in selected vocational training institutions and workplaces in Kampala, Uganda
(Taylor&Francis: International Journal of Occupational Safety and Ergonomics, 2015-12-23) Denis, Kintu; Kyakula, Michael; Kikomeko, Joseph
Several industrial accidents, some of them fatal, have been reported in Uganda. Causes could include training gaps in vocational training institutions (VTIs) and workplaces. This study investigated how occupational safety training in VTIs and workplaces is implemented. The study was carried out in five selected VTIs and workplaces in Kampala. Data were collected from instructors, workshop technicians, students, workshop managers, production supervisors, machine operators and new technicians in the workplaces. A total of 35 respondents participated in the study. The results revealed that all curricula in VTIs include a component of safety but little is practiced in VTI workshops; in workplaces no specific training content was followed and there were no regular consultations between VTIs and industry on safety skills requirements, resulting in a mismatch in safety skills training. The major constraints to safety training include inadequate funds to purchase safety equipment and inadequate literature on safety.
An advanced continuum damage mechanics model for predicting the crack progress process based on the consideration of the influence of crack direction under quasi-static load
(Elsevier: International Journal of Mechanical Sciences., 2017-09) Yun, Kumchol; Wang, Zhenqing; Ronald, Sakaya; Pak, Yongchol
In reality the wrong crack path can be generally obtained in the case of arbitrary crack propagation by traditional continuum damage mechanics (CDM). In this paper a novel advanced continuum damage mechanics (ACDM) method is proposed, which can predict the crack propagation and fracture behavior correctly for the structures. The material property degradation method, which is usually used when simulating the structures within the framework of CDM, is advanced based on considering the influence of crack direction. The maximum tensile stress criterion is used to predict the damage initiation and crack propagation direction and the advanced CDM used to predict the damage evolution process in meso-level under the quasi-static load. It can directly evaluate the propagation process of the discrete crack and the fracture strength for structures using the continuum model as well as not using discontinuum model. The algorithm for the application of our advanced CDM theory in the numerical simulation based on finite element method (FEM) is presented. ACDM model is not only a simple and useful model which can easily be used in FEM framework but also a phenomenological model based on the concept of crack propagation. The simulation results by our ACDM are compared with the experiment results and the ones and from cohesive zone method and extended finite element method for good agreements to be achieved.
Performance of burnt clay hollow block slab under seismic action in Uganda
(Kyambogo University (unpublished work), 2018-09) Kiberu, Faisal
A storeyed building has different structural elements each working to complement the other in resisting seismic actions. Since most of the building mass is present at floor levels, earthquake induced inertia forces primarily develop at the floor levels due to ground vibrations from which they travel horizontally through the slabs and beams to columns and wa11s, and then to the foundations where they are dispersed to the ground. Ninety five percent (95%) of storeyed buildings in Kampala the capital city of Uganda have their slabs constructed with burnt clay ho11ow block reinforced concrete slabs. Slabs containing hollow blocks are constructed with the hollow side of blocks end to end running in one direction, with a rib between rows of blocks in which steel reinforcement is laid. This constrains the slab to act as one-way spanning. For a structure subjected to seismic loading, the requirement for a diaphragm is that the slab should have equal strength in both horizontal directions. This is because horizontal seismic action is described by two orthogonal components considered as independent and represented by the same response spectrum. According to EN 1998, (Euro Code 8), one of the guiding principles governing conceptual design against seismic hazard is the bi-directional resistance and stiffness at storey level. Seismic load is applied to the slab as a compressive load in the plane of the slab. This study determined the load capacity of hollow blocks parallel and perpendicular to the boles in the plane of the slab. Hollow block slabs measuring 750 x 800mm were produced. These were cured for 28days and loaded parallel and perpendicular to the direction of hollow blocks and ribs. Also, the hollow blocks were loaded parallel and perpendicular to the direction of holes. It was found that the load capacity of burnt clay hollow blocks when loaded parallel to holes varied from I 03.35kN - l 23.93kN giving a compressive stress of 2.3 /mm2 - 2.8N/mm2 , whereas the load capacity, perpendicular to the direction of holes ranged from 45.6kN - 47.4kN giving a compressive strength of I .ON/mm2 - l.05N/rnm2• For the slab, the failure load varied from 3 I 5kN - 375kN when loaded parallel to the rib, giving a stress of l .97N/mm2 - 2.34N/mm2 and the failure stress perpendicular to ribs varied from l.04N/nun2 - l.2N/mm2.
Influence of urbanization on performance of public utilities: a case of national water and sewerage corporation in lira municipality, Uganda
(Kyambogo University (un published work), 2018-11) Okite, George
The study sought to investigate the influence of urbanization on the pe1formance of NWSC in LMC with objectives to establish the relationship between urbanization and performance, to establish the challenges faced by NWSC as a result of urbanization, and to develop a framework for efficient delivery of services in LMC. Qualitative, quantitative approaches and interview, survey and document review methods were employed. A case study design and a model were applied to achieve the objectives. 384 participants were targeted and 381 responded. From the study findings, there was a significant positive correlation (rho = .487) between urban growth and development and Service delivery by NWSC. It is shown that the significance of the correlation (p = .000) is less than the recommended critical significance at 0.05, thus not rejected. It was also established that discriminatory urban planning with a mean of 3.50, lack of political will with a mean of 3.66, unplanned water supply with mean score of 3.46 were the most silent challenges faced by NWSC in the performance of her duties. Policy reform and water contamination fetched low mean score of 2.93 and 3.29 and constituted the least challenges that affect NWSC. The multiple regression model with all four predictors produced R2R2 =0.463, F (6, 92) = 4.176, p < 0. OOI .The research findings indicated that there was a strong positive relationship (R= 0.214) between the variables. The study also revealed that 46.3% of the NWSC performance factors can be explained by the independent variables. The municipality ought to expedite the planning process so as to ensure settlement and housing projects are setup with minimal interference on utility and other access lines which will enable service providers have a manageable operational cost. Key words: Urbanization; Performance, Public Utilities
Assessment of equipment productivity in building construction projects in Uganda
(Kyambogo University[unpublished work], 2018-12) Asaya, Andrew Peter
Management of construction equipment in building construction projects is an important factor to run projects in a successful manner. The focus of this study was to identify the factors affecting equipment productivity, to establish how these factors impacted on equipment productivity, with the aim of improving equipment productivity in Uganda. Using a cross sectional study design, data were collected from a total of 340 respondents in different construction sites in Kampala by use of questionnaires. Descriptive statistics were used to analyse the respondents' demographic characteristics and the mean and standard deviation was used to identify factors affecting construction equipment productivity. The identified factors were subjected to regression analysis and a model was developed to improve equipment productivity. The study established that human resource factors affecting equipment productivity were; technical skills of staff, experience of the operator, and motivation of staff. It was further established that equipment factors affecting equipment productivity were; equipment break down, quality of equipment, working cycle capacity, and age of equipment. With regards to the environmental factors affecting equipment productivity, the study found that weather conditions and access, were the leading factors affecting equipment productivity. It was established that holding other factors constant, environmental factors affect equipment productivity by 6.4% and the remaining 93.6% is explained by other factors. Project managers should therefore hire experienced and well-motivated equipment operators and in order to improve equipment productivity in building construction project. Key words: Equipment Productivity, Human resource, Environment, Building construction
Assessing the impact of bitumen types on the Performance of asphalt concrete road pavement construction in Uganda
(Kyambogo University (un published work), 2018-12) Mpaata, Steven
This research was conducted to assess the impact of local asphalt binders on the performance of asphalt concrete road pavement construction in Uganda. The bitumen samples were collected from ongoing road construction projects where asphalt concrete made pan of the pavement. The sampling was done in accordance with procedures provided in BS EN 58: 2012 and BS EN 475: 2000. Testing was carried out in Central Materials Laboratory, Tan Roads. Dar Es Salaam, Tanzania to confirm binder classification and obtain performance properties. The penetration tests, fluidity and pumping tests conducted on the bitumen samples confirmed compliance with specifications. It was noted that all penetration grade bitumen samples gave softening points lower than the allowable limits implying in-service performance challenges. Most of the samples did not comply with physical property requirements when compared with the binder specifications implying that they arc susceptible to rutting and fatigue damage. Binder Temperature zoning based on Strategic Highway Research Program of asphalt grading system was completed in fourteen zones and presented on a map. Three temperature zones were confirmed incorporating Perfom1ance Grade (PG) 70+ 3 in most of the Northern, far Eastern and Kasese regions, PG 64+6 for most of Central and PG 58+3 for far Western regions bordering with Rwanda and Democratic Republic of Congo. This study introduced a robust testing regime and acceptance criteria to be used in future asphalt designation and construction in Uganda. Accordingly. value engineering was achieved based on increased time intervals of road
African food insecurity in a changing climate: the roles of science and policy
(Wiley Online Library: Food and Energy Security, 2018-12-12) Onyutha, Charles
African population is projected to double to 2.48 billion people by 2050. The population increase poses a serious challenge of increasing food supply to meet the future demand. This challenge is compounded by climate change impacts on agriculture. In this paper, how poverty contributes to household food insecurity is explored and measures suggested to help address this challenge. To plan adaptation measures, linkages among food insecurity, poverty, and illiteracy should be considered. For the sub-Saharan Africa (SSA), adaptation (focused on poverty alleviation) should be prioritized and preferred to mitigation. Enhancement of adaptive capacity should not only be tailored toward empowerment of women but also made highly localized to household levels. Generally, efforts could be geared toward yield gap closure, addressing challenges regarding food distribution, promoting non-farm income-generating activities, and unification of government priorities in agriculture and food security. Government in each country of the SSA should ensure that governance strongly embraces transparency, accountability, and integrity otherwise as it is said a fish rots from the head down. Estimates of uncertainty in predicting future climate and their implications on expenditure related to adaptation should to always be made in an integrated way and reported to support actionable policies. To increase credibility in climate prediction especially at local scales, advances toward improving climate models (for instance by refining spatiotemporal scales, enhancing models’ capacity to reproduce observed natural variability in key climatological variables like rainfall) should be made, and this requires support from the investment in climate science. Science–policy interfacing is required in planning and implementation of measures for adapting to climate change impacts. In summary, food insecurity and persistent poverty especially in the SSA should be of direct relevance and concern at a global scale. Thus, global collaboration in science is key to achieve food security in the SSA.
Osmotic consolidation of expansive soil
(Japanese Geotechnical Society Special Publication, 2019) Sam, Bulolo; E.C., Leong
The mechanical behavior of expansive soils is influenced by the concentration of salts in their pore water. Research has shown that volume change of soil can occur due to a difference in salt concentration in the pore water between different zones of the soil as a result of either osmotically-induced consolidation or osmotic consolidation. The effect of the salt concentration of the pore water in unsaturated soil mechanics can be expressed as osmotic suction. Very little work has been done to quantify the mechanical equivalence of osmotically-induced and osmotic consolidation. This study attempts to quantify the mechanical stress equivalence of consolidation of an expansive soil submerged in a salt solution. Two remoulded soil samples of kaolin - bentonite mixture in proportions of 70% – 30% and 90% - 10%, (kaolin – bentonite) by dry mass were submerged in different concentrated salt solutions to investigate the effect of osmotic suction. Results showed that osmotic suction caused an additional settlement over the consolidation settlement under a mechanical stress but does not affect the soil compressibility. The osmotic coefficient of volume change (mπ) is only a fraction of the coefficient of volume change (mv).
Hydrological model supported by a step-wise calibration against sub-flows and validation of extreme flow events
(MDPI, 2019-01-31) Onyutha, Charles
Most hydrological models have fixed structures and their calibrations are typified by a conventional approach in which the overall water balance closure is considered (without a step-wise focus on sub-flows’ variation). Eventually, hydrological modelers are confronted with the difficulty of ensuring both the observed high flows and low flows are accurately reproduced in a single calibration. This study introduced Hydrological Model focusing on Sub-flows’ Variation (HMSV). Calibration of HMSV follows a carefully designed framework comprising sub-flow’s separation, modeling of sub-flows, and checking validity of hydrological extremes. The introduced model and calibration framework were tested using hydro-meteorological data from the Blue Nile Basin of Ethiopia in Africa. When the conventional calibration approach was adopted through automatic optimization strategy, results from the HMSV were found highly comparable with those of five internationally well recognized hydrological models (AWBM, IHACRES, SACRAMENTO, SIMHYD, and TANK). The new framework enhanced the HMSV performance for reproducing quantiles of both high flows and low flows. The combination of flow separation and step-wise calibration of hydrological model against sub-flows enhances the modeler’s physical insight in identifying which areas need focus in modeling to obtain meaningful simulation results, especially of extreme events. The link for downloading the HMSV is provided
A computational methodology for simulating quasi-brittle fracture problems
(Elsevier: Computers & Structures, 2019-04-15) Yun, Kumchol; Wang, Zhenqing; Chang, Mengzhou; Liu, Jingbiao; Kim, Tae-Jong; Son, Namjin; Ji, Kyongsu; Ronald, Sakaya
The paper focuses on an efficient and simple methodologies for simulating the three dimensional (3D) quasi-brittle fracture problems. Strain-softening is performed on the elements by a developed anisotropic continuum damage model that has more effective capability in crack path prediction and is easily available in standard finite elements. In the present damage model, the damaged stiffness tensor is constructed to form a crack surface, and the energy dissipation in the damaged element is only allowed in the direction perpendicular to the crack plane. Crack surface is divided into crack lines and crack triangles based on the first introduced crack surface discretization, and the application scope of local tracking algorithm is extended from two dimension to 3D. The present tracking algorithm not only guarantees the continuity and stability of the predicted crack path by solving the topological problems but also has low computational cost, keeping the advantages of local tracking. The method does not identify the crack plane within each element, but it couples well with smeared crack method by identifying all the elements through which the crack surface passes. The high efficiency and stability of the present approach are verified by resolving several 3D benchmark problems in failure analysis.
Dynamically dimensioned search embedded with piecewise opposition-based learning for global optimization
(2019-05-26) Xu, Jianzhong; Yan, Fu; Yun, Kumchol; Ronald, Sakaya; Li, Fengshu; Guan, Jun
Dynamically dimensioned search (DDS) is a well-known optimization algorithm in the field of single solution-based heuristic global search algorithms. Its successful application in the calibration of watershed environmental parameters has attracted researcher’s extensive attention. The dynamically dimensioned search algorithm is a kind of algorithm that converges to the global optimum under the best condition or the good local optimum in the worst case. In other words, the performance of DDS is easily affected by the optimization conditions. Therefore, this algorithm has also suffered from low robustness and limited scalability. In this work, an improved version of DDS called DDS-POBL is proposed. In the DDS-POBL, two effective methods are applied to improve the performance of the DDS algorithm. Piecewise opposition-based learning is introduced to guide DDS search in the right direction, and the golden section method is used to search for more promising areas. Numerical experiments are performed on a set of 23 classic test functions, and the results represent significant improvements in the optimization performance of DDS-POBL compared to DDS. Several experimental results using different parameter values demonstrate the high solution quality, strong robustness, and scalability of the proposed DDS-POBL algorithm. A comparative performance analysis between the DDS-POBL and other powerful algorithms has been carried out by statistical methods by using the significance of the results. The results show that DDS-POBL works better than PSO, CoDA, MHDA, NaFA, and CMA-ES and gives very competitive results when compared to INMDA and EEGWO. Moreover, the parameter calibration application of the Xinanjiang model shows the effectiveness of the DDS-POBL in the real optimization problem.
Contribution of climatic variability and human activities to stream flow changes in the Haraz River basin, Northern Iran
(Journal of Hydro-environment Research, 2019-06) Pirnia, Abdollah; Darabi, Hamid; Choubin, Bahram; Omidvar, Ebrahim; Onyutha, Charles; Haghighi, Ali Torabi
In northern Iran’s Haraz River basin between 1975 and 2010, hydrological sensitivity, double mass curve, and Soil and Water Assessment Tool (SWAT) methods were applied to monitoring and analysing changes in stream flow brought on by climatic variability and human activities. Applied to analyse trends in annual and seasonal runoff over this period, the sequential MK test showed a sudden change point in stream flow in 1994. The study period was, therefore, divided into two sub-periods: 1975–1994 and 1995–2010. The SWAT model showed obvious changes in water resource components between the two periods: in comparison to the period of 1975–1994, sub-watershed-scale stream flow and soil moisture decreased during 1995–2010. Changes in evapotranspiration were negligible compared to those in stream flow and soil moisture. The hydrological sensitivity method indicated that climatic variability and human activities contributed to 29.86% and 70.14%, respectively, of changes in annual stream flow, while the SWAT model placed these contributions at 34.78% and 65.21%, respectively. The double mass curve method indicated the contribution of climatic variability to stream flow changes to be 57.5% for the wet season and 22.87% for the dry season, while human activities contributed 42.5% and 77.13%, respectively. Accordingly, in the face of climatic variability, measures should be developed and implemented to mitigate its impacts and maintain eco-environmental integrity and water supplies.
Assessing the effect of different mortar mixes on strength of burnt clay brick masonry wall
(Kyambogo University(Unpublished work), 2019-10) Owino, Stephen
Following the tremendous increase in population growth rate in Uganda from 12.6 million people in 1980 to 34.6 million people in 2014, there has been an increase in housing units from 2.6 million house in 1980 to 7.34 million houses in 2014. Despite of this increase in housing units, the population has surpassed the demand leading to a deficit of 200, 000 housing units annually. The National Housing and population census of 2014 revealed that the increased housing units is constructed of permanent materials at 43.7% with burnt clay bricks leading at 36.4% followed by mud and poles at 33.6% and these are materials used without the knowledge of their strength and properties. Hence, the need to assess its strength so as to protect the inhabitants against accidents and loss of lives. Research findings indicated that 100% of the structural design firms do not design masonry structures made of burnt clay bricks but instead specify them as infills. 100% survey on 102 sites established that the commonly used mortar mix ratios range between 1:7 to 1:14 far different from the perceived mortar mix ratios of 1:3 to 1:6 as a result of the use of one bag of cement to a number of wheelbarrows and these resulted into a compressive strength of 5.92N/mm2 to 1.87N/mm2 respectively far below the intended compressive strength of 17.8N/mm2 to 6.82N/mm2. Experimental tests on burnt clay bricks has established varying compressive strength with an average of 7.3N/mm2 to 2.06N/mm2 and this was attributed to water absorption, method of manufacture and the soil type. Results on burnt clay masonry walls constructed of most used mortar mix ratios established that , the compressive strength of the wall greatly reduced with increasing value of mortar mix ratios. Conclusively, the wall strength was much influenced by the strength of mortar, indicating that the weaker the strength of mortar the weaker the wall strength and vice versa however strong the brick may be, hence high mix ratios beyond 1:6 should not be used in the construction of masonry clay brick walls to avoid structural failures.
Quality of packaged drinking water along its production and distribution chain: a case of central and eastern Uganda
(Kyambogo University (un published work), 2019-10) Agonza, Deogratious
Access to safe and affordable drinking water is one of core targets under Sustainable Development Goals: 6. Bottled water is a path way for such safe access as from 1990, with currently more than 40 registered brands amidst the high demand for it, mainly at functions and events in spite of the varying consumer perception. This study aimed at assessing packaged drinking water quality along its production and distribution chain. The study focused on; assessing consumer perception on bottled water quality, its quality during production processes and on local markets in Central and Eastern Regions of Uganda. Findings from the study showed that majority of the respondents from the consumer perception survey, 86% agreed to bottled water being tasty, 42% agreed that it has odour and 13% agreed that it has colour. Furthermore, during sample testing, evident results of appearance, aroma, texture and taste confirmed were recorded and guided selection of study case factories of the study. All the tested 24 samples from production and 60 samples from market for the 3 bottled water brands tested met National Drinking Water Standards. However, they all showed differences in key parameters in the four towns. The parameters also showed degree of changes depending on storage facilities. The difference mainly differed by; location; market avenue; storage all attributed to probably, travel distance, temperature difference and expiry dates. Bottled water is; safe for consumption, not coloured but bears taste and odour as related to consumer’s perception. Key words; Bottled water, Taste, Odour, Colour, parameter, quality.
Developing a model for cost performance improvement of road maintenance projects in northern Uganda – case study of Uganda National Roads Authority
(Kyambogo University (un published work), 2019-11) Abonga, Alfred Alexis
Government has put in place plans for road development and maintenance and has improved on its budget allocations, in order to boost tourism, agriculture and mining, among others. However, road maintenance remains a challenge due to cost deviations, inflation of unit costs by contractors and delays in maintenance interventions. This has resulted into maintainable sections of the networks to slip into rehabilitation realm, therefore increasing maintenance backlog. This study examined Cost Performance Improvement of road maintenance projects in Northern Uganda considering Uganda National Roads Authority. The main objective of the study was to develop a model to improve cost performance in road maintenance projects. The study was conducted in four UNRA stations in Northern Uganda, namely Arua, Gulu, Kitgum and Moyo Stations using a simple random selection. Both qualitative and quantitative data were collected, using survey questionnaires and documentary reviews from a sample size of 60 elements. Data was analyzed using correlations, regression analysis and descriptive analysis. Wearing course & shoulder works experienced 64.3% negative cost deviations while drainage improvements experienced 21.4%. Material price fluctuations, with 80.9% of respondents, and equipment availability and failures, with 81% of respondents, were key factors, believed to have influence on cost deviations. A Cost Performance Improvement model, developed using a multivariate regression analysis of budgeted cost elements, is proposed to address inaccurate costing of the budget elements. The study concluded that road maintenance projects experience negative cost deviations due to problems related to Clients’ Project management & contract administration, labor management, financial management, contractor’s site management and design & documentation factors. The research recommends a study into the effect of different management styles on project cost deviations since it varies from one contract manager to another.
Assessment of impacts of land use changes on water resources of river Mpanga catchment
(Kyambogo University, 2019-11) Turyahabwe, Catherine
Mpanga Catchment has in recent decades been exposed to changes in land use/cover (LULC). This could have been due to intensive agricultural activities to sustain the needs of the increasing population. Transition in land use/cover tends to impact on the hydrology of a given catchment. This study assessed the impacts of land use changes on water resources of Mpanga catchment. The study was three-fold. Firstly, land use changes were identified and analysed. In the second step, the question of whether land use changes impacted on water resources was answered through hydrological modelling using Soil and Water Assessment Tool (SWAT). SWAT was automatically calibrated and validated using daily data from 2003 to 2013. Thirdly, the model was applied to conduct scenario analysis. Major land use/covers included cropland, forest, pasture, wetland, water body and settlement. Cultivated area increased by 31.79% while grassland and forests decreased by 31.79% and 11.38%, respectively. Hydrological model performance evaluation yielded Nash-Sutcliffe model efficiency (NSE) 0.86 and 0.77 during calibration and validation periods, respectively. Changes in the land uses between 2000 and 2014 increased stream flow ratios from 0.49 to 0.54, surface runoff from 0.26 to 0.33 and evapotranspiration ratios reduced from 0.49 to 0.44. Scenario analysis showed that the catchment was more influenced by the land use changes with respect to dry than wet conditions. Thus, control measures like agroforestry, deep tillage and banding should be adopted to minimize run off and facilitate infiltration and ground water recharge. Key words: Catchment, land use/cover, water resources, scenarios, hydrological modelling
Abating the effects of different land use activities on eutrophication of Kabaka’s lake Kampala - Uganda
(Kyambogo University, 2019-11) Mutyaba, Abel
Various land uses resulting from urbanization in Kampala the capital city of Uganda, have reduced the natural pollutant filtration value of the wetlands. This has in turn led to a decline in the water quality and gradual eutrophication of available water bodies such as Kabaka’s lake, characterised with green colored water, foul smells, and tastes. The aim of this study was to assess eutrophication management strategies for abatement of the effects of the different land use activities on natural water quality of Kabaka’s lake. The study focused on; classification of downloaded Landsat imagery for the last 25 years, mapping of pollution hotspots and nutrient distribution with GIS, and assessment of both external (constructed wetland) and internal (dredging) eutrophication extenuation measures. Following the research showed that Kabaka’s lake catchment land use has been significantly (p<0.005) been redistributed, with buildup area increasing by 78.5%, vegetated area reducing by 37.2% and water reducing by 1.8%. This has not only significantly reduced the lakes receiving wetland footprint by 92.2% (p=0.000003) but also increased the nutrient load in the catchment mainly from; garage oil spillages, car washing bays wastewater, and sewerage. The 80,596 m2 Lake’s light attenuation is currently algae dominate, limited by nitrogen and classified under oligotrophic class of lakes (Trophic State Index<40) with a threat of eutrophication in an estimate of 25 years. Construction of a wetland in the remaining 1.34 acres of natural wetland will significant reduce Total Phosphorus by 35% and Total Nitrate by 45% (p = 0.05), whereas dredging the lake will reduce both by 80% (p = 0.0005). Watershed and proper land use management, establishment of riparian buffer vegetation and a diversion channel and community sensitization were some of the study recommendations. Key words; Land use, Nutrient concentration, Eutrophication
Applicability of public private partnerships in development of infrastructure in higher institutions of learning in Uganda
(Kyambogo University (un published work), 2019-11) Mabonga, Sylvia Namakoye
Public Private Partnership system is considered an innovative finance strategy which offers good prospects for global construction industry. Yet, since the adoption of the system in Uganda, the benefits have not been fully realized. This research, therefore aimed at establishing the extent of use of the Public Private Partnerships, the question of continuity or and starting to use it, inspirations and barriers affecting its applicability in higher institutions of learning in Uganda. The study adopted a cross sectional survey research design, with both quantitative and qualitative approaches. With a sample size of 138 respondents that were purposively selected, regression and correlation analyses were performed to establish the significance of the bio-data and inspirations to show the determination to continuation of the PPP system. The survey results show that PPPs have only been embraced to a minimal extent of 4% in higher institutions of learning in Uganda. Further analysis showed there was interest to continue or start using PPPs. Inspirations were established as; availability of funds for development, completed within stipulated time, cost and transfer of all risk to the contracting party in fig. 4.12. Barriers were found as; PPPs projects are feared to be complex and risky, lack of expertise on establishing and managing projects, lack of legislation or compatibility with the existing procurement ordinances and lack of political support. This research can be impactful to policymakers to adopt when implementing future projects by use of a developed framework in fig. 4.15 that would offer solutions to the identified barriers. Key words: Barriers, Continuity, Development, Infrastructure, Inspirations, Public Private Partnerships.
Application of value analysis concept on construction cost of low volume roads in Uganda
(Kyambogo University (un published work), 2019-11) Okello, Emmanuel
The success of implementation of highway infrastructure projects is usually measured against three parameters; quality, time and cost. However, some of these projects do not achieve expected project goals in terms of quality. Secondly, project delivery is not within a reasonable amount of time, and finally, costs are not in line with their budget limits. This study applied Value Analysis (VA) methodology in the construction of Low Volume Roads (LVRs) in Uganda, to mitigate the aspects of time and cost but still ensuring that the functionality and quality aspects are not jeopardized, through the generation of innovative alternatives. The methodology included document review and cost analysis of LVR projects previously implemented in ten districts in Northern and Eastern Uganda. In this study VA technique involved the employment of a composite or mixed method of work, incorporating both mechanization and manual labour during the Road Formation Phase (RFP), as opposed to the existing labour based methods. The VA technique was applied to two construction projects, that is: the construction of 800 meters of LVR in Financial Year (FY) 2017/18 in Kole District which project was undertaken by the researcher and during the construction of a 1,200 meter LVR in Bukedea District in the same year. Comparison of the cost when the VA is used, with the current cost through hypothesis testing was done, and the alternative hypothesis that the cost reduces on application of the mixed method VA technique during the Road Formation Phase (RFP) was upheld at 95% confidence level. It was established that average cost per metre of LVR when using the conventional labour methods was UGX. 250,000, while an average cost per metre of UGX. 228,157 was achieved when the mixed method approach was used, thereby realizing an 8.7% reduction in the average cost per metre of the construction of LVRs. The researcher thus concluded that the cost of LVR construction significantly reduces when VA is applied during the RFP. The researcher recommended the use of the mixed method VA technique for the ongoing and future LVR construction projects under the Low Cost Seal (LCS) Program and proposed that further research should be done to apply VA on the sealing phase of LVR construction. Key Words: Value Analysis, Cost per Metre, Mixed Method, Road Formation Phase, Low Volume Roads, Low Cost Seal.

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