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Sugarcane (Saccharum officinarum) bagasse (SCB) is a biomass of agricultural waste obtained from sugarcane processing that has been found in abundance globally. Due to its abundance in nature, researchers have been harnessing this biomass for numerous applications such as in energy and environmental sustainability. However, before it could be optimally utilised, it has to be pre-treated using available methods. Different pre-treatment methods were reviewed for SCB, both alkaline and alkali–acid process reveal efficient and successful approaches for obtaining higher glucose production from hydrolysis. Procedures for hydrolysis were evaluated, and results indicate that pre-treated SCB was susceptible to acid and enzymatic hydrolysis as > 80% glucose yield was obtained in both cases. The SCB could achieve a bio-ethanol (a biofuel) yield of > 0.2 g/g at optimal conditions and xylitol (a bio-product) yield at > 0.4 g/g in most cases. Thermochemical processing of SCB also gave excellent biofuel yields. The plethora of products obtained in this regard have been catalogued and elucidated extensively. As found in this study, the SCB could be used in diverse applications such as adsorbent, ion exchange resin, briquettes, ceramics, concrete, cement and polymer composites. Consequently, the SCB is a biomass with great potential to meet global energy demand and encourage environmental sustainability.

Noise from transportation systems is unavoidable in urban areas and can be harmful to human health. The noise generated by selected transportations systems in Ilorin, an urban area in central Nigeria, was studied by direct measurements and the use of questionnaires. Measurements were taken at the airport, train station and different locations for vehicular traffic. Questionnaires were also administered on residents of these areas to elicit information on the perception of transportation noise in the areas. The results show that all the studied locations produced maximum noise levels in excess of the 85-dBA acceptable tolerable limit for humans. The train station produced the highest stepwise noise levels due to the motion and horning of the locomotive engines. The study also established distances in which the sound level is safe over a specific period of time for each of the studied noise sources. These are of 18.84 m, 161.21 m, 13.85 m and 15.08 m for aircraft take-off, movement and horning of railway locomotive engine and vehicular traffic inside and outside town respectively. Suggested solutions were that residential buildings, academic areas and hospitals should not be located too close to sources of transportation noise and the need for enforcement of relevant noise control laws is to be pursued. Keywords: Noise pollution, sound pressure level, equivalent sound level, acceptable noise level, noise perception

Traffic signs, pavement markings and other road safety assets such as speed bumps are provided on roadway facilities to enhance traffic flow and safety. They will however perform their functions effectively if they meet the basic requirements of i. fulfill a need ii. command attention iii. convey a clear simple meaning iv. command respect from road users and v. give adequate time for proper response. It is noticed and rightfully observed by the Nigeria National Council on Works that these assets on Nigeria roads are not adequately managed and maintained. Some of them are not well positioned, some are missing and some others are damaged. There is therefore the need to assess the existing roadway assets, their conditions and adequacy, and generate a database needed for their effective operation, management and maintenance. The study thus aims at addressing the observed inadequacies by proffering a GPS-GIS-based solution. The objectives are to i. carry out an inventory of existing road signs and markings; ii. determine their adequacy or otherwise and iii. develop a GIS- based road signage management system. It is anticipated that the application of the developed system will enhance the performance of the agencies responsible for the operations of the road assets.

Water allocation planning in an equitable and sustainable way is intrinsically complex. This study proposes a water resource allocation system using an integrated Soil and Water Assessment Tool and Water Evaluation and Planning tool (SWAT-WEAP) model for hydrological simulation and prognostic scenarios sustainability prediction. The study explores the use of Digital Elevation Model (DEM), soil and land raster image in deriving physiographic information for land degradation impact assessment, quantification of optimal water allocation and generation of minimum ecosystem water requirement. Consequently, the SWAT quantifies the catchment water yield before been allocated optimally based on percentage dependable flow rates of 70% and 85% reliability flow regime at Makurdi, Nigeria discharge station. The WEAP model assesses the water resources utilization following scenarios adaptation by riparian users. Both models performed satisfactorily for streamflow and water yield prediction and resource sharing both in the calibration and validation phases with a correlation coefficient (R2) of 0.57–0.74 and root squared error (RSR) of 0.66–0.82. The results show how drainage network, channel length, drainage boundary, slope, and sub-catchment geometric properties demonstrate Geographic Information Systems (GIS) utility in morphoclimatic impacts assessment as a data management, scenario analysis, and decision support tool in water management for the Lower Benue River Basin, Nigeria. Planners and decision-makers need to consider several integrated plans as alternatives to adapting to climate change impacts and anthropogenic human activities in resolving the unmet demands.

Shea biodiesel (SBD) was produced and blended with diesel at various proportions to produce 100B (SBD), 75B, 50B, 25B, and D (diesel) as fuel types. The SBD and other fuel types were characterised by ASTM standard methods for its physicochemical properties. The fuel types were used in a compression ignition engine (CIE) to test for its fuel consumption, (FC) specific fuel consumption (SFC), brake thermal efficiency (BTE), exhaust temperature (ET) and emission characteristics hydrocarbon (HC), carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxide (NOx) and sulphur dioxide (SO2). The physicochemical properties of SBD in terms of density, kinematic viscosity, flash point, cloud and pour points, and cetane number were 884.7 kg/m3, 5.69 mm2/s, 165 oC, 12 oC, 9 oC and 55, respectively; while those of diesel were 860.4 kg/m3, 2.6 mm2/s, 73 oC, 2.4 oC, -9 oC and 49, respectively. The results were within the range of the standard. The results obtained at 12 Nm torque for SFC, FC, BTE, and ET for SBD were 0.21 kg/kW.h, 0.71 kg/h, 12.69%, and 365 oC, respectively, while those of diesel were 0.31 kg/kW.h, 1.12 kg/h, 8.46%, and 330 oC, respectively. These results show that the SBD and diesel possessed similarity in terms of performance. The SBD is environmentally friendly compared to diesel. This study shows that the SBD possessed quality alternative replacement to diesel suitable for a CIE.

This study presents the impact of global warming on precipitation patterns in Ilorin, Nigeria, and its implications on the hydrological balance of the Awun basin under the prevailing climate conditions. The study analyzes 39 years of rainfall and temperature data of relevant stations within the study areas. Simulated data from the Coupled Global Climate model for historical and future datasets were investigated under the A2 emission scenario. Statistical regression and a Mann-Kendall analysis were performed to determine the nature of the trends in the hydrological variables and their significance levels, while a Soil and Water Assessment Tool (SWAT) was used to estimate the water balance and derive the stream flow and yield of the Awun basin. The study revealed that while minimum and maximum temperatures in Ilorin are increasing, rainfall is generally decreasing. The assessment of the trends in the water balance parameters in the basin indicates that there is no improvement in the water yield as the population increases. This may result in major stresses to the water supply in the near future.

Optimization models have been developed to maximize annual energy generation from the Doma dam, subject to the constraint of releases for irrigation, ecological purposes, the water supply, the maximum yield from the reservoir and reservoir storage. The model was solved with LINGO software for various mean annual inflow exceedence probabilities. Two scenarios of hydropower retrofitting were considered. Scenario 1, with the reservoir inflows at 50%, 75%, and 90% probabilities of exceedence, gives the total annual hydropower as 0.531 MW, 0.450 MW and 0.291 MW, respectively. The corresponding values for scenario 2 were 0.615 MW, 0.507 MW, and 0.346 MW respectively. The study also considered increasing the reservoir’s live storage to 32.63Mm3 by taking part of the flood storage so that the maximum draft increases to 7 Mm3. With this upper limit of storage and draft with reservoir inflows of 50%, 75% and 90% probabilities of exceedence, the hydropower generated increased to 0.609 MW, 0.540 MW, and 0.347 MW respectively for the scenario 1 arrangement, while those of scenario 2 increased to 0.699 MW, 0.579MW and 0.406 MW respectively. The results indicate that the Doma Dam is suitable for the production of hydroelectric power and that its generation potential is between 0.61 MW and 0.70 MW.

Many Dams have been constructed in different parts of the world and for different purposes. While these dams have in most cases served the reason for their construction, the resultant environmental impact have been a subject of concern. The creation of a reservoir not only changes the ecology and hydrology of the environment, the lives of nearby residents is also affected. This study assessed the impact of the University of Ilorin Dam on the health condition of the University community. The Dam was built for the main purpose of water supply to university community. Data on the water related disease reported and documented at the university clinic was obtained to cover pre and post construction period while the perception and behavioral pattern of the community as related to water and sanitation was studied with the help of a structured questionnaire. The chi-squared test was applied to establish that a relationship do exist between the dam construction and the occurrence of some diseases especially Malaria. The study have also shown that the dam imposes no significant negative health impact on the university community. http://dx.doi.org/10.4314/njt.v36i1.28

Water allocation management in an equitable and sustainable way is intrinsically complex. Climate change and managerial policy have further adversely altered the hydrologic cycles thus, threatens to worsen the current supply-demand imbalance. This study was conducted in Lower Benue River Catchment in the North Central crevice of Nigeria, to assess the consequences of climate change due to changing rainfall patterns in the area and proposes different prognostic scenarios adaptation on the current and future water allocation sharing in the area. The Soil and Water Assessment Tool (SWAT) was interfaced with Map window - Geographic Information Systems (GIS) for the basin hydrological modeling to assess the impact of the watershed characteristics on runoff and subsequent quantification of the catchment water yield before been allocated optimally based on percentage dependable flow rates of 70% and 85% reliability flow regime at Makurdi, Nigeria discharge station. Furthermore, the Water Evaluation and Planning tool (WEAP) model was used for the water resources utilization simulation and adaptation scenarios by the different riparian users. The SWAT model performed satisfactorily for streamflow and water yield prediction both in the calibration and validation phases with a R2 of 0.57-0.68 and RSR of 0.66-0.82, while the WEAP model calibration and validation at the same station with rainfall data posted a R2 of 0.64 and 0.89. Planners and decision-makers on water resources allocation, therefore, need to consider several integrated plans as alternatives to the adaptation to climate change impacts and anthropogenic activities in resolving the unmet demands.

Hydrological models are very useful for predictions in many ungauged basins across the world. There are many hydrological models available for discharge data generation with different complexities and varied input parameter requirements. Studies have shown that models with many input parameters do not necessarily perform better than those with few input parameters. Basin morphometric parameters play significant roles in the conversion of rainfall to runoff and obtaining good estimates of these parameters for use in runoff models is sometime challenging as Inaccurate input into models can propagate errors and make the models to perform poorly. This study employs the method of principal component analysis to reduce the number of morphometric parameters required to run a runoff model without losing any major information. Parameters for five selected study basins in central Nigeria were measured and analysed. The result shows that three morphometric parameters (Fitness Ratio, Ruggedness Number and Watershed Eccentricity) can adequately represent other parameters as an input into a runoff model for the basins. This reduces significantly the time and effort needed to compute all the parameters which in actual fact may not improve the quality or efficiency of the runoff model.

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In this study, probability analysis was performed on peak daily rainfall data in order to predict rainfall interval values and to determine the best fit functions in some parts of Nigeria. The selected towns are Kaduna, Kano, Yola, Jos, Damaturu and Maiduguri. The obtained peak daily rainfall values were subjected to Gumbel, Log-Gumbel, Normal, Log-Normal, Pearson and Log-Pearson probability distributions. Mathematical equation for probability distribution functions were established for each town and used to predict peak rainfall. The predicted values were subjected to goodness of fit tests such as Chi-square, Correlation Coefficient, Coefficient of Determination and Errors of Estimates to determine how best the fits are. The model that satisfies the tests adequately was selected as the best fit model. The study revealed that the peak rainfall at Kaduna, Jos, Kano, Yola and Damaturu are best fitted by log-Gumbel, while log- Pearson distribution is suitable for predicting peak rainfall in Maiduguri. The result also shows that the occurrences of peak daily rainfall depth of 100 mm and above are rare in the selected areas. Keywords: Peak rainfall, Probability distribution models, Return period, Probability interval and goodness of fit tests

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This study focused on the evaluation of willingness-to-pay (WTP) for sustainable household water use in Ilorin, Nigeria. The study involved assessment of the existing water supply situation particularly considering water use indicators such as demography, adequacy of existing water supply system and WTP for reliable supply. Field work involved the use of structured questionnaire to obtain data on household water use and WTP for a reliable water supply of the sampled houses consisting three land use patterns. Stata/SE 8.0 and Microsoft EXCEL software were employed to evaluate the variables that affect WTP for improved household water use while ccontingency Valuation Method was adopted to evaluate the WTP for reliable and sustainable service delivery. The findings of the study revealed that: approximately 70 % of total sampled households were connected to municipal supply out of which 13 % indicated satisfaction in terms of sufficiency and 87 % used alternative sources to augment water supply; consumers are willing to pay an average sum of N 737.22 per month for improved water supply services and; gender, water quality and household income level have significant impact on WTP at 5% level of significance. There is the need to put in place a framework to enhance improvement of system reliability and sustainability. Keywords : Evaluation, willingness, reliability, sustainability, household, water

The article identifies the role of Geomatics in the highly interdisciplinary disaster management to include identification and mapping of hazard prone areas, deformation monitoring of hazard prone areas and massive engineering structures, production of rescue maps and assessment of damages among others. A case study of surveying activities in the proposed flood management of Asa River in Ilorin metropolis, Nigeria was presented. The study identified possible causes of the flood to include silting along the river, blockades of free flow of water resulting from human activities such as dumping of refuse in the river and natural causes such as growth of vegetation along the river channel. The study recommends the development and deployment of Geomatics potentials in the three phases of disaster management namely; pre-disaster phase, disaster phase and post disaster phase. Keywords: Geomatics, Disaster, Mapping, Assessment, Management

Generic factors (weather, environment, vehicles, fixed roadway characteristics, pedestrian and traffic streams) singly or jointly influence the free flow speed. This paper, therefore, presents the outcome of the quantitative evaluation of the influence of these factors on the free flow speed on an arterial in a medium-sized urban settlement in Nigeria. Instantaneous speeds of forty test vehicles were observed at lull periods on the 7.1km-Offa Garage-Emir’s Road, Ilorin, with simultaneous collection of data on drivers’ and vehicle ages, passenger occupancy, roadside parked vehicles and businesses. The geometric properties of the arterial were earlier established and segmented to four uniform sections. Result of computations using the category and statistical analysis show that the environment, pedestrian and roadway geometry have negative influences on the free flow speed. This can be confirmed by the poor relationship between free flow speed and these factors, with R 2 values of 14.9-55%, and lower average free flow speed of commercial saloon cars on wet pavement than on dry pavement, with 12% percentage reduction. Adoption of design and analysis of traffic stream in Ilorin and other urban settlements in Nigeria is, therefore, recommended. http://dx.doi.org/10.4314/njt.v35i3.2

This paper reports the evaluation of households’ usage of the current solid waste management system (SWMS) within the city of Ilorin, central Nigeria and investigates the determinants of household’s willingness-to-Pay (WTP) for its improvement. Data was collected with the aid of a structured questionnaire administered to households within four neighbourhoods that represent the major subdivisions in the metropolis. The multiple regression model was applied in explaining household’s usage of the current system and WTP.The study found that 36% and 64% respectively of the households were unsatisfied and moderately satisfied with the current waste management system. The combined effect of household’s demographic profiles, geometric profile and position of waste management facility gave a significant fitted model to show the relationship between household’s willingness to pay and the considered predictors. http://dx.doi.org/10.4314/njt.v34i4.28

Municipal solid waste collected in Nigeria are often disposed of in uncontrolled dumpsites and/or burnt in the open spaces and consequently causing significant pollution on surface water, ground water and the air. An investigational study was carried out on the level of pollution on groundwater near Gbagede dumpsite in Kwara state. Ground water samples, GW1, GW2, GW3 were taken at three different locations: 186 m, 290 m, and 326 m from the edge of the dumpsite. Physicochemical parameters evaluated include; pH, total hardness, Total Dissolved Solids, Total Suspended Solids, alkalinity, turbidity, Chemical Oxygen Demand, Biochemical Oxygen Demand, Dissolved Oxygen, Nitrate ion, Chloride ion, Sulphate ion, Electrical conductivity, Calcium ion and Magnesium ion using standard laboratory procedures. The results of the evaluations were compared with the World Health Organization (WHO) and Nigerian Standard for Drinking Water Quality (NSDWQ) to establish its suitability for human consumption. Results fell within the stipulated range of WHO and NSDWQ standard for drinking water. It was however observed that the water quality improves with distance from the dumpsite. Statistical analyses indicated mild differences among all the parameters tested for in the samples at 95% confidence level. Uncontrolled accumulation of leachates from the dumpsite may pose potential risk to the source of water for the community in the near future. It was recommended that the dumpsite be relocated from the current residential area.Key Words: Groundwater, Assessment, Contaminants, Solid-waste, Water quality