Engr. Dr. Andy Obinna Ibeje is a Christian male, who is married with children. He is an indigene of Umuaka in Njaba L.G.A. of Imo state, Nigeria. He is currently the Head of Civil Engineering Department at the Imo State University, Owerri. He obtained B.Eng., M.Eng. and Ph.D. degrees from the Federal University of Technology, Owerri (FUTO) in 2006, 2010 and 2014 respectively in Water Resources Engineering Technology. He also holds Post Graduate Diploma (PGD) in statistics from the Imo State University, Owerri. He obtained a Professional Diploma in Education (PDE) from the Alvan Ikokwu Federal College of Education, Owerri in 2017. He is also registered with the Council for the Regulation of Engineering in Nigeria (COREN) and is a member of the following engineering and professional bodies viz: Nigerian Society of Engineers (NSE), Nigerian Institution of Water Engineers (NIWE), Nigerian Institute of Management (NIM) and Teachers Registration Council of Nigeria (TRCN). Dr Ibeje has supervised several undergraduates and postgraduates in the Imo State University, Owerri and has served as an external examiner in some other high institutions. He has also headed several panels on administrative and academic challenges in the University system. His research interests include stochastic hydrology, uncertainty analysis, statistical drought analysis, statistical hydrology, time series analysis, statistical trend detection, groundwater hydrology and climate change impacts. Dr Ibeje has also participated in several Nigerian TETFUND-assisted projects related to appropriate technologies for water and wastewater treatment, water quality modelling and applications of operations research in wastewater reuse and pollution control.
Insufficient length of streamflow record poses challenges in capturing extreme events, frequencie... more Insufficient length of streamflow record poses challenges in capturing extreme events, frequencies, and sequences crucial for effective water resources systems design. Consequently, simulation and application of statistically similar streamflow values becomes imperative. In this study, two Markov-based models, namely the Thomas-Fiering (T-F) model and the Autoregressive (AR) model, were developed based on a log-normal probability distribution to synthesize monthly and annual flows using a decade of historical data (1980-1989) collected from the Umulokpa gauging station in the Adada River catchment of Enugu State, Nigeria. Except for the month of December (p = 0.03), no significant difference (p > 0.05) was observed between the monthly and annual model-predicted streamflows. However, both models demonstrated limitations in fully capturing the characteristics of the observed flows, particularly regarding Kurtosis. Further accuracy assessment from computed correlation coefficients (0.018 for T-F and 0.122 for AR), along with root mean square error (RMSE) values (12.84 for T-F and 11.95 for AR), indicate that while both models deviated from the observed flows, the AR model demonstrated superior performance compared to the T-F model. However, to apply these models reliably, for future flow prediction in the Adada catchment, streamflow data from rivers with comparable catchment characteristics is essential. Autoregressive Markov Flood model Synthesis Streamflow Thomas-fiering CORRESPONDENCE Benjamin Nnamdi Ekwueme
NIGERIAN JOURNAL OF TECHNOLOGICAL DEVELOPMENT, 2021
The major components of the effluents from cassava processing industries are cyanide and starch. ... more The major components of the effluents from cassava processing industries are cyanide and starch. However it is suspected that cyanide inhibits the treatment of cassava wastewater. The experimental data were successfully fitted to a polynomial model which was used to optimize the treatment processes at a laboratory scale. The Monod and Michealis-menten models for cassava wastewater treatment was successfully calibrated and validated in an ABR system. For Michealis-Menten model, the maximum substrate utilization rate is estimated in the range: 2866.88 to 1432.84 mgl-1 and for Monod's model, it is estimated in the range: 493 to 1242 mgl-1, which is more realistic, hence validating the empirical model as more accurate than the former, which is theoretical. The result revealed that the inhibitor constant decreased from 9.9989 to 1.6101mgl-1 as the number of baffles increased from 3 to 10. To reach a maximum COD removal efficiency of 99%, it was found that the aspect ratio of 10, 20 baffles, cyanide inhibition constant of 30 mg/l and influent flow rate of 0.8 l/min, are the required optimum operating conditions of the anaerobic baffled reactors.
Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout t... more Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout the world. A review of the literature indicates that, understanding the hydraulics of waste stabilization ponds is critical to their optimization, the research in this area has been relatively limited and that there is a poor mechanistic understanding of the flow behavior that exists within these systems. This explains why there is no generally acceptable model for predicting its performance. The two-dimensional computational fluid dynamics (CFD) model developed in this study was extensively tested on the waste stabilization pond located in the campus of the University of Nigeria, Nsukka which was used as the field pond and also on a laboratory scale waste stabilization pond obtained from literature. Although the model may be solved by several methods, this research was limited to computational method; numerical solution using finite difference method was used in solving the two-dimensional partial differential equations at steady state conditions. In order to validate the quality of the model, its results were compared with the experimental data from the field and the lab-scale ponds. The results obtained were encouraging, prediction of pond performance with measured values shows that correlation coefficient of 0.82 was obtained, representing an accuracy of 82%. The 2-D model was then used in series of investigative studies such as; effect of single inlet and outlet structures at different positions in the pond, effect of multiple inlet and outlets on the pond's performance, variation of pond performance with depth, effect of short-circuiting on pond treatment efficiency, effect of baffles on pond performance using laboratory-scale pond data and comparison with tracer studies. In all, the results agree with literature.
SSRG International Journal of Civil Engineering, 2021
Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout t... more Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout the world. A review of the literature indicates that, understanding the hydraulics of waste stabilization ponds is critical to their optimization, the research in this area has been relatively limited and that there is a poor mechanistic understanding of the flow behavior that exists within these systems. This explains why there is no generally acceptable model for predicting its performance. The computational fluid dynamics (CFD) model developed in this study was extensively tested on the waste stabilization pond located in the campus of the University of Nigeria, Nsukka which was used as the field pond and also on a laboratory scale waste stabilization pond obtained from literature. Although the model may be solved by several methods, this research was limited to computational method; numerical solution using finite difference method was used in solving the one-, two-and three-dimensional partial differential equations at steady state conditions. In order to validate the quality of the model, its results were compared with the experimental data from the field and the lab-scale ponds. The results obtained were encouraging, prediction of pond performance with measured values shows that a correlation coefficient of (0.92-0.95) was obtained, representing an accuracy of 94% using the 3-D CFD model, an ultimate result that demonstrates that actual dispersion in the pond is three-dimensional. The 2-D model gave an accuracy of 82%. The 1-D model gave an accuracy of 73%, showing that truly dispersion in the pond is not unidirectional. The 3-D model was then used in series of investigation studies such as; effect of single inlet and outlet structures at different positions in the pond, effect of multiple inlet and outlets on the pond's performance, variation of pond performance with depth, effect of short-circuiting on pond treatment efficiency, effect of baffles on pond performance using laboratoryscale pond data and comparison with tracer studies. In all, the results agree with literature. While it was previously concluded that a CFD model cannot always be expected to precisely predict the performance of a field pond, this work has validated its use.
FUOYE Journal of Engineering and Technology (FUOYEJET), 2021
Lack of funds and political will have made continuous gauging of rivers in Nigeria impossible, th... more Lack of funds and political will have made continuous gauging of rivers in Nigeria impossible, thus stalling the development of surface water resources. In order to address this anomaly; this study is focused on developing discharge rating curve, for selected streams in Imo-Anambra river basin of southeast Nigeria, which is capable of predicting discharge from stage. Ten years monthly stage and discharge records, measured with stream gauges, for Rivers Adada in Enugu state, Ajali in Anambra state, Ivo in Ebonyi State, Otamiri in Imo state, and Imo (Umuopara) in Abia state, were used in estimating the rating curve models using simple linear regression as: = 23.719 0.715 , = 9.605 0.4204 , = 10.123 −0.1435 , = 10.95 0.6829 and = 35.925 1.2046. All the rating curve equations were validated using coefficient of determination which yielded values of 98.54%, 97.38%, 17.31%, 89.98% and 99.43%, but the empirical discharge-stage model of River Ivo was discarded as the model produced poor performance and lacked the features of a rating curve. The rating curve of Imo River predicted the highest discharge for equivalent input values of stage because of its large cross-section at the gauging station. The developed rating curve models are therefore recommended for discharge prediction in these catchment areas with limited streamflow records.
Journal of Research and Innovation in Engineering, 2020
In the Niger Delta area of Nigeria, especially Okarki and Okparaki communities of Ahoada West Loc... more In the Niger Delta area of Nigeria, especially Okarki and Okparaki communities of Ahoada West Local Government Area, Rivers State, water resources are deteriorating in quality as greater use is made of them and more effluent is discharged into them. Water samples for eleven wells and ten river fetching points were randomly collected for water quality analysis. To determine the optimal allocation of water resources that is permissible based on the quality of the sources of water supply, a technique for allocating water resources in the form of transportation programming was formulated and applied in the study. The model results showed that for minimization of iron concentration that a supply of a mixture of 58L/day from Okarki river, 101.21L/day from Okarki well and 41.05L/day from Okparaki well should be sufficient to meet the total domestic demand and keep the concentration Iron within the WHO acceptable limits for drinking water. For agricultural water demand, a mixture of supplies of 63.45L/day from Okparaki well and 58.5L/day from Okparaki river was required. In the case of minimization of Copper concentration in the water supply, the result of the optimization that by mixing a supply of 58L/day, 101.2L/day and 41.05L/day from Okarki River, Okarki well and Okparaki well respectively, the domestic demand and WHO limits could be met. However, to meet agricultural water demand, 32.35L/day from Okparaki well and 97.07L/day from any other water supply with no copper concentration was required. This new approach has therefore proved to be useful for management and operation of water supply systems in a rural area.
The study investigated the effect of computer modelling on the students’ academic performance in ... more The study investigated the effect of computer modelling on the students’ academic performance in Structural Design (CVE 322) of Civil Engineering Department, Imo State University, Owerri. The research used a pre-test–post-test equivalent control group experimental design. Eighty year-three students were randomly sampled from a population of 496 year-three to year-five students of the department. The mean score, standard deviation and t-test at 0.05 level of significance were used for analysis. The results revealed computer modelling (CM) has little or no effect on students’ academic performance because the differences between the average pre-test and post-test scores for students taught using CM and those of students taught using the traditional (lecture) method (TM) were 21.20 and 21.34 respectively. The findings further showed that the mean score and standard deviation of male students were 36.40 and 3.29 respectively while those of female students were 41.80 and 3.42 respectively. This implied that there is a gender difference in the academic performance of students exposed to CM; female students perform better than the male students when taught with CM. It can be concluded that CM is the better learning technique among female engineering students than their male counterparts especially while teaching Structural Design among year 3 students.
Around the world today, road pavement is increasingly vulnerable and Southeast Nigeria is no exce... more Around the world today, road pavement is increasingly vulnerable and Southeast Nigeria is no exception. To this end, the Delphi technique is used in this study to ascertain experts opinions in order to identify and prioritize road pavements vulnerable to climate change in Abia and Imo states of Southeast Nigeria. As a measure of stability, standard deviation of two rounds of questionnaire responses was used to assess the level of convergence of opinions of 10-member Delphi panel. The Delphi panel achieved acceptable level of agreement at threshold values of standard deviation = 0.10 for stability and mean = 0.20 for consensus. Out of 14 federal roads considered in the study, 1 road had high vulnerability status, 5 roads had medium vulnerability status, 5 roads were rated low vulnerability and 2 roads were rated very low vulnerability. The only highly vulnerable road is from Abia state. This study has shown that the vulnerability of road pavements to climate change can be assessed comprehensively using collective and subjective judgement in the form of Delphi technique. Government should therefore apply adaptive maintenance plans that reflect the relative vulnerability rating of these roads.
ABUAD Journal of Engineering Research and Development (AJERD), 2020
The linearity of hydro-climatic relations is required to analyse the dependence of streamflow on ... more The linearity of hydro-climatic relations is required to analyse the dependence of streamflow on some climatic variables. This study is focused on evaluating the relationship and significance of average annual climatic variables in estimating annual runoff in Ajali River located in Enugu State, Nigeria. 1983-2006 records of annual climatic and runoff data are used to develop multiple linear regression (MLR) model, expressing the annual runoff as a function of the annual climatic variables. In addition, hypotheses are tested using t-test and one-way ANOVA. At 0.05 level of significance, the results revealed that the model was not statistically significant in predicting runoff in Ajali River basin. MLR model evaluated as Q = 2.81I 0.024 S-0.037 H-0.055 W-0.028 R 0.096 Ts 0.172 E-0.111 P 0.016 , revealed a non-linear relationship between runoff and the climatic system while the multiple coefficient of determination, R 2 is estimated as 0. 228, meaning that climatic variables account for 22.8% of the variation in runoff. Also, the significant test revealed that none of the climate variables is a significant predictor of annual runoff (p ˃ 0.05) in Ajali watershed. Based on the findings, it can be deduced that non-climatic factors such as human activities, account for 77.2% of the annual runoff variation in the watershed. To ensure sustainable water supply in the study area, efforts should be geared towards the control of human activities in the river basin.
Hydrologic designs require accurate estimation of quartiles of extreme floods. But in many develo... more Hydrologic designs require accurate estimation of quartiles of extreme floods. But in many developing regions, records of flood data are seldom available. A model framework using the dimensionless index flood for the transfer of Flood Frequency Curve (FFC) among stream gauging sites in a hydrologically homogeneous region is proposed. Key elements of the model framework include: (1) confirmation of the homogeneity of the region; (2) estimation of index flood-basin area relation; (3) derivation of the regional flood frequency curve (RFFC) and deduction of FFC of an ungauged catchment as a product of index flood and dimensionless RFFC. As an application, 1983 to 2004 annual extreme flood from six selected gauging sites located in Anambra-Imo River basin of southeast Nigeria, were used to demonstrate that the developed index flood model: = 0.495 0.6676 , overestimated flood quartiles in an ungauged site of the basin. It is recommended that, for wider application, the model results can be improved by the availability and use of over 100 years length of flood data spatially distributed at critical locations of the watershed.
FUOYE Journal of Engineering and Technology (FUOYEJET), 2020
The study outlines a frequency distribution study on the highest annual flood statistics in Niger... more The study outlines a frequency distribution study on the highest annual flood statistics in Niger River located at Shintaku hydrologic Station for a period of 58years. In order to determine optimal model for highest annual flood analysis generalised extreme value, Log normal, Gumbel maximum, Generalised Pareto and Log Pearson III, were tested. Based on error produced by criteria of goodness of Fit tests, the optimal model was determined. Results obtained indicated that Log Pearson type III was best to model maximum flood magnitude of Niger River at Shintaku station. The flood frequency curve was therefore derived using Log Pearson type III frequency distribution. Flood frequency curve showed that return periods of 50 and 100 years with the probabilities of 2% and1% respectively, yielded discharges of 15300m 3 /s and 15600m 3 /s respectively. These results were strongly influenced by their topographical, geographical and climatic factors. The findings of this work will be useful for design engineers in deciding the dimension of hydraulic structures such as spillway, dams, canals, bridges and levees among others. Future studies are required to include flood forecasting in the development of inundation maps for Niger River.
Nigerian Research Journal of Engineering and Environmental Sciences, 2018
To ascertain the geomorphological characteristics of watersheds in developing countries is diffic... more To ascertain the geomorphological characteristics of watersheds in developing countries is difficult due to lack of equipment. The method of morphometric analysis in which computations involving the dimensions of catchment landforms reveal the geology, hydrology and geomorphology of the watershed is proposed in this study. This approach was applied to Orammiriukwa river system in Imo State, Nigeria. Dimensions of catchment landforms were measured from atlas map of the river using planimeter. Linear and areal aspects of morphometric paramters were computed. The results of the study indicate that there is no strong geological control in the development of the drainage area. The form factor of 0.754 showed that the river system is highly elongated and flood is difficult to manage. With the length of overland flow of 4.558km, low drainage intensity of 0.34, low infiltration number of 0.000352, the basin indicates very less permeable subsoil , high susceptibility to flooding and gully erosion due to high runoff in the watershed. The results are consistent with the observed hydrological activities in the area as revealed by previous studies. The findings of this study have strengthened the understanding of the hydrologeological and geomorphological characteristics of the Orammiriukwa river system through simple geometric computations. This approach can be extended to other watersheds where assess to equipment is difficult.
NIPES Journal of Science and Technology Research, 2020
Understanding historical baseflow characteristics is essential for effective planning and managem... more Understanding historical baseflow characteristics is essential for effective planning and management of water resources in the Otamiri River Basin, Nigeria. Baseflow separation and recession analysis have been two of the main tools for understanding runoff generation in catchments. This study is focused on separating baseflow from 1979-1989 monthly total runoff for Otamiri River watershed using the recession analysis. Baseflow was estimated from the monthly streamflow records as difference using the Hewlett and Hibbert method. The results showed that baseflow accounted for 67.19% of total streamflow indicating that more than half of streamflow in Otamiri River is derived from baseflow.
GLOBAL JOURNAL OF PURE AND APPLIED SCIENCES VOL. 25, 2019: 91-95, 2020
This study is aimed at finding the level of wastewater treatment at two sites that would achieve ... more This study is aimed at finding the level of wastewater treatment at two sites that would achieve the desired concentrations at a minimum total cost for a river that received wastewater effluent from some other two point sources located at two sites. Pollutant concentrations and stream flow in the stream at selected reaches were obtained. Linear programming model was developed incorporating waste transfer coefficients. The model was applied at Nworie River in Imo State, Nigeria. The model solution was obtained using graphical method and the results revealed that 80% treatment efficiencies met the stream standards for the design stream flow and waste load condition at a total minimum cost. The study shows that least-cost waste removal efficiencies could be determined without prior knowledge of the cost functions.
Insufficient length of streamflow record poses challenges in capturing extreme events, frequencie... more Insufficient length of streamflow record poses challenges in capturing extreme events, frequencies, and sequences crucial for effective water resources systems design. Consequently, simulation and application of statistically similar streamflow values becomes imperative. In this study, two Markov-based models, namely the Thomas-Fiering (T-F) model and the Autoregressive (AR) model, were developed based on a log-normal probability distribution to synthesize monthly and annual flows using a decade of historical data (1980-1989) collected from the Umulokpa gauging station in the Adada River catchment of Enugu State, Nigeria. Except for the month of December (p = 0.03), no significant difference (p > 0.05) was observed between the monthly and annual model-predicted streamflows. However, both models demonstrated limitations in fully capturing the characteristics of the observed flows, particularly regarding Kurtosis. Further accuracy assessment from computed correlation coefficients (0.018 for T-F and 0.122 for AR), along with root mean square error (RMSE) values (12.84 for T-F and 11.95 for AR), indicate that while both models deviated from the observed flows, the AR model demonstrated superior performance compared to the T-F model. However, to apply these models reliably, for future flow prediction in the Adada catchment, streamflow data from rivers with comparable catchment characteristics is essential. Autoregressive Markov Flood model Synthesis Streamflow Thomas-fiering CORRESPONDENCE Benjamin Nnamdi Ekwueme
NIGERIAN JOURNAL OF TECHNOLOGICAL DEVELOPMENT, 2021
The major components of the effluents from cassava processing industries are cyanide and starch. ... more The major components of the effluents from cassava processing industries are cyanide and starch. However it is suspected that cyanide inhibits the treatment of cassava wastewater. The experimental data were successfully fitted to a polynomial model which was used to optimize the treatment processes at a laboratory scale. The Monod and Michealis-menten models for cassava wastewater treatment was successfully calibrated and validated in an ABR system. For Michealis-Menten model, the maximum substrate utilization rate is estimated in the range: 2866.88 to 1432.84 mgl-1 and for Monod's model, it is estimated in the range: 493 to 1242 mgl-1, which is more realistic, hence validating the empirical model as more accurate than the former, which is theoretical. The result revealed that the inhibitor constant decreased from 9.9989 to 1.6101mgl-1 as the number of baffles increased from 3 to 10. To reach a maximum COD removal efficiency of 99%, it was found that the aspect ratio of 10, 20 baffles, cyanide inhibition constant of 30 mg/l and influent flow rate of 0.8 l/min, are the required optimum operating conditions of the anaerobic baffled reactors.
Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout t... more Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout the world. A review of the literature indicates that, understanding the hydraulics of waste stabilization ponds is critical to their optimization, the research in this area has been relatively limited and that there is a poor mechanistic understanding of the flow behavior that exists within these systems. This explains why there is no generally acceptable model for predicting its performance. The two-dimensional computational fluid dynamics (CFD) model developed in this study was extensively tested on the waste stabilization pond located in the campus of the University of Nigeria, Nsukka which was used as the field pond and also on a laboratory scale waste stabilization pond obtained from literature. Although the model may be solved by several methods, this research was limited to computational method; numerical solution using finite difference method was used in solving the two-dimensional partial differential equations at steady state conditions. In order to validate the quality of the model, its results were compared with the experimental data from the field and the lab-scale ponds. The results obtained were encouraging, prediction of pond performance with measured values shows that correlation coefficient of 0.82 was obtained, representing an accuracy of 82%. The 2-D model was then used in series of investigative studies such as; effect of single inlet and outlet structures at different positions in the pond, effect of multiple inlet and outlets on the pond's performance, variation of pond performance with depth, effect of short-circuiting on pond treatment efficiency, effect of baffles on pond performance using laboratory-scale pond data and comparison with tracer studies. In all, the results agree with literature.
SSRG International Journal of Civil Engineering, 2021
Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout t... more Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout the world. A review of the literature indicates that, understanding the hydraulics of waste stabilization ponds is critical to their optimization, the research in this area has been relatively limited and that there is a poor mechanistic understanding of the flow behavior that exists within these systems. This explains why there is no generally acceptable model for predicting its performance. The computational fluid dynamics (CFD) model developed in this study was extensively tested on the waste stabilization pond located in the campus of the University of Nigeria, Nsukka which was used as the field pond and also on a laboratory scale waste stabilization pond obtained from literature. Although the model may be solved by several methods, this research was limited to computational method; numerical solution using finite difference method was used in solving the one-, two-and three-dimensional partial differential equations at steady state conditions. In order to validate the quality of the model, its results were compared with the experimental data from the field and the lab-scale ponds. The results obtained were encouraging, prediction of pond performance with measured values shows that a correlation coefficient of (0.92-0.95) was obtained, representing an accuracy of 94% using the 3-D CFD model, an ultimate result that demonstrates that actual dispersion in the pond is three-dimensional. The 2-D model gave an accuracy of 82%. The 1-D model gave an accuracy of 73%, showing that truly dispersion in the pond is not unidirectional. The 3-D model was then used in series of investigation studies such as; effect of single inlet and outlet structures at different positions in the pond, effect of multiple inlet and outlets on the pond's performance, variation of pond performance with depth, effect of short-circuiting on pond treatment efficiency, effect of baffles on pond performance using laboratoryscale pond data and comparison with tracer studies. In all, the results agree with literature. While it was previously concluded that a CFD model cannot always be expected to precisely predict the performance of a field pond, this work has validated its use.
FUOYE Journal of Engineering and Technology (FUOYEJET), 2021
Lack of funds and political will have made continuous gauging of rivers in Nigeria impossible, th... more Lack of funds and political will have made continuous gauging of rivers in Nigeria impossible, thus stalling the development of surface water resources. In order to address this anomaly; this study is focused on developing discharge rating curve, for selected streams in Imo-Anambra river basin of southeast Nigeria, which is capable of predicting discharge from stage. Ten years monthly stage and discharge records, measured with stream gauges, for Rivers Adada in Enugu state, Ajali in Anambra state, Ivo in Ebonyi State, Otamiri in Imo state, and Imo (Umuopara) in Abia state, were used in estimating the rating curve models using simple linear regression as: = 23.719 0.715 , = 9.605 0.4204 , = 10.123 −0.1435 , = 10.95 0.6829 and = 35.925 1.2046. All the rating curve equations were validated using coefficient of determination which yielded values of 98.54%, 97.38%, 17.31%, 89.98% and 99.43%, but the empirical discharge-stage model of River Ivo was discarded as the model produced poor performance and lacked the features of a rating curve. The rating curve of Imo River predicted the highest discharge for equivalent input values of stage because of its large cross-section at the gauging station. The developed rating curve models are therefore recommended for discharge prediction in these catchment areas with limited streamflow records.
Journal of Research and Innovation in Engineering, 2020
In the Niger Delta area of Nigeria, especially Okarki and Okparaki communities of Ahoada West Loc... more In the Niger Delta area of Nigeria, especially Okarki and Okparaki communities of Ahoada West Local Government Area, Rivers State, water resources are deteriorating in quality as greater use is made of them and more effluent is discharged into them. Water samples for eleven wells and ten river fetching points were randomly collected for water quality analysis. To determine the optimal allocation of water resources that is permissible based on the quality of the sources of water supply, a technique for allocating water resources in the form of transportation programming was formulated and applied in the study. The model results showed that for minimization of iron concentration that a supply of a mixture of 58L/day from Okarki river, 101.21L/day from Okarki well and 41.05L/day from Okparaki well should be sufficient to meet the total domestic demand and keep the concentration Iron within the WHO acceptable limits for drinking water. For agricultural water demand, a mixture of supplies of 63.45L/day from Okparaki well and 58.5L/day from Okparaki river was required. In the case of minimization of Copper concentration in the water supply, the result of the optimization that by mixing a supply of 58L/day, 101.2L/day and 41.05L/day from Okarki River, Okarki well and Okparaki well respectively, the domestic demand and WHO limits could be met. However, to meet agricultural water demand, 32.35L/day from Okparaki well and 97.07L/day from any other water supply with no copper concentration was required. This new approach has therefore proved to be useful for management and operation of water supply systems in a rural area.
The study investigated the effect of computer modelling on the students’ academic performance in ... more The study investigated the effect of computer modelling on the students’ academic performance in Structural Design (CVE 322) of Civil Engineering Department, Imo State University, Owerri. The research used a pre-test–post-test equivalent control group experimental design. Eighty year-three students were randomly sampled from a population of 496 year-three to year-five students of the department. The mean score, standard deviation and t-test at 0.05 level of significance were used for analysis. The results revealed computer modelling (CM) has little or no effect on students’ academic performance because the differences between the average pre-test and post-test scores for students taught using CM and those of students taught using the traditional (lecture) method (TM) were 21.20 and 21.34 respectively. The findings further showed that the mean score and standard deviation of male students were 36.40 and 3.29 respectively while those of female students were 41.80 and 3.42 respectively. This implied that there is a gender difference in the academic performance of students exposed to CM; female students perform better than the male students when taught with CM. It can be concluded that CM is the better learning technique among female engineering students than their male counterparts especially while teaching Structural Design among year 3 students.
Around the world today, road pavement is increasingly vulnerable and Southeast Nigeria is no exce... more Around the world today, road pavement is increasingly vulnerable and Southeast Nigeria is no exception. To this end, the Delphi technique is used in this study to ascertain experts opinions in order to identify and prioritize road pavements vulnerable to climate change in Abia and Imo states of Southeast Nigeria. As a measure of stability, standard deviation of two rounds of questionnaire responses was used to assess the level of convergence of opinions of 10-member Delphi panel. The Delphi panel achieved acceptable level of agreement at threshold values of standard deviation = 0.10 for stability and mean = 0.20 for consensus. Out of 14 federal roads considered in the study, 1 road had high vulnerability status, 5 roads had medium vulnerability status, 5 roads were rated low vulnerability and 2 roads were rated very low vulnerability. The only highly vulnerable road is from Abia state. This study has shown that the vulnerability of road pavements to climate change can be assessed comprehensively using collective and subjective judgement in the form of Delphi technique. Government should therefore apply adaptive maintenance plans that reflect the relative vulnerability rating of these roads.
ABUAD Journal of Engineering Research and Development (AJERD), 2020
The linearity of hydro-climatic relations is required to analyse the dependence of streamflow on ... more The linearity of hydro-climatic relations is required to analyse the dependence of streamflow on some climatic variables. This study is focused on evaluating the relationship and significance of average annual climatic variables in estimating annual runoff in Ajali River located in Enugu State, Nigeria. 1983-2006 records of annual climatic and runoff data are used to develop multiple linear regression (MLR) model, expressing the annual runoff as a function of the annual climatic variables. In addition, hypotheses are tested using t-test and one-way ANOVA. At 0.05 level of significance, the results revealed that the model was not statistically significant in predicting runoff in Ajali River basin. MLR model evaluated as Q = 2.81I 0.024 S-0.037 H-0.055 W-0.028 R 0.096 Ts 0.172 E-0.111 P 0.016 , revealed a non-linear relationship between runoff and the climatic system while the multiple coefficient of determination, R 2 is estimated as 0. 228, meaning that climatic variables account for 22.8% of the variation in runoff. Also, the significant test revealed that none of the climate variables is a significant predictor of annual runoff (p ˃ 0.05) in Ajali watershed. Based on the findings, it can be deduced that non-climatic factors such as human activities, account for 77.2% of the annual runoff variation in the watershed. To ensure sustainable water supply in the study area, efforts should be geared towards the control of human activities in the river basin.
Hydrologic designs require accurate estimation of quartiles of extreme floods. But in many develo... more Hydrologic designs require accurate estimation of quartiles of extreme floods. But in many developing regions, records of flood data are seldom available. A model framework using the dimensionless index flood for the transfer of Flood Frequency Curve (FFC) among stream gauging sites in a hydrologically homogeneous region is proposed. Key elements of the model framework include: (1) confirmation of the homogeneity of the region; (2) estimation of index flood-basin area relation; (3) derivation of the regional flood frequency curve (RFFC) and deduction of FFC of an ungauged catchment as a product of index flood and dimensionless RFFC. As an application, 1983 to 2004 annual extreme flood from six selected gauging sites located in Anambra-Imo River basin of southeast Nigeria, were used to demonstrate that the developed index flood model: = 0.495 0.6676 , overestimated flood quartiles in an ungauged site of the basin. It is recommended that, for wider application, the model results can be improved by the availability and use of over 100 years length of flood data spatially distributed at critical locations of the watershed.
FUOYE Journal of Engineering and Technology (FUOYEJET), 2020
The study outlines a frequency distribution study on the highest annual flood statistics in Niger... more The study outlines a frequency distribution study on the highest annual flood statistics in Niger River located at Shintaku hydrologic Station for a period of 58years. In order to determine optimal model for highest annual flood analysis generalised extreme value, Log normal, Gumbel maximum, Generalised Pareto and Log Pearson III, were tested. Based on error produced by criteria of goodness of Fit tests, the optimal model was determined. Results obtained indicated that Log Pearson type III was best to model maximum flood magnitude of Niger River at Shintaku station. The flood frequency curve was therefore derived using Log Pearson type III frequency distribution. Flood frequency curve showed that return periods of 50 and 100 years with the probabilities of 2% and1% respectively, yielded discharges of 15300m 3 /s and 15600m 3 /s respectively. These results were strongly influenced by their topographical, geographical and climatic factors. The findings of this work will be useful for design engineers in deciding the dimension of hydraulic structures such as spillway, dams, canals, bridges and levees among others. Future studies are required to include flood forecasting in the development of inundation maps for Niger River.
Nigerian Research Journal of Engineering and Environmental Sciences, 2018
To ascertain the geomorphological characteristics of watersheds in developing countries is diffic... more To ascertain the geomorphological characteristics of watersheds in developing countries is difficult due to lack of equipment. The method of morphometric analysis in which computations involving the dimensions of catchment landforms reveal the geology, hydrology and geomorphology of the watershed is proposed in this study. This approach was applied to Orammiriukwa river system in Imo State, Nigeria. Dimensions of catchment landforms were measured from atlas map of the river using planimeter. Linear and areal aspects of morphometric paramters were computed. The results of the study indicate that there is no strong geological control in the development of the drainage area. The form factor of 0.754 showed that the river system is highly elongated and flood is difficult to manage. With the length of overland flow of 4.558km, low drainage intensity of 0.34, low infiltration number of 0.000352, the basin indicates very less permeable subsoil , high susceptibility to flooding and gully erosion due to high runoff in the watershed. The results are consistent with the observed hydrological activities in the area as revealed by previous studies. The findings of this study have strengthened the understanding of the hydrologeological and geomorphological characteristics of the Orammiriukwa river system through simple geometric computations. This approach can be extended to other watersheds where assess to equipment is difficult.
NIPES Journal of Science and Technology Research, 2020
Understanding historical baseflow characteristics is essential for effective planning and managem... more Understanding historical baseflow characteristics is essential for effective planning and management of water resources in the Otamiri River Basin, Nigeria. Baseflow separation and recession analysis have been two of the main tools for understanding runoff generation in catchments. This study is focused on separating baseflow from 1979-1989 monthly total runoff for Otamiri River watershed using the recession analysis. Baseflow was estimated from the monthly streamflow records as difference using the Hewlett and Hibbert method. The results showed that baseflow accounted for 67.19% of total streamflow indicating that more than half of streamflow in Otamiri River is derived from baseflow.
GLOBAL JOURNAL OF PURE AND APPLIED SCIENCES VOL. 25, 2019: 91-95, 2020
This study is aimed at finding the level of wastewater treatment at two sites that would achieve ... more This study is aimed at finding the level of wastewater treatment at two sites that would achieve the desired concentrations at a minimum total cost for a river that received wastewater effluent from some other two point sources located at two sites. Pollutant concentrations and stream flow in the stream at selected reaches were obtained. Linear programming model was developed incorporating waste transfer coefficients. The model was applied at Nworie River in Imo State, Nigeria. The model solution was obtained using graphical method and the results revealed that 80% treatment efficiencies met the stream standards for the design stream flow and waste load condition at a total minimum cost. The study shows that least-cost waste removal efficiencies could be determined without prior knowledge of the cost functions.
Proceedings of the 4th NIWE International Water Conference on Innovative Solutions to Water Supply and Water Infrastructural Challenges in Nigeria of The Nigerian Institution of Water Engineers (NIWE), 2021
Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout t... more Waste stabilization ponds (WSP) are used extensively to provide wastewater treatment throughout the world. A review of the literature indicates that, understanding the hydraulics of waste stabilization ponds is critical to their optimization, the research in this area has been relatively limited and that there is a poor mechanistic understanding of the flow behavior that exists within these systems. This explains why there is no generally acceptable model for predicting its performance.The three-dimensional computational fluid dynamics (CFD) model developed in this study was extensively tested on the waste stabilization pond located in the campus of the University of Nigeria, Nsukka which was used as the field pond and also on a laboratory scale waste stabilization pond obtained from literature. Although the model may be solved by several methods, this research was limited to computational method; numerical solution using finite difference method was used in solving the three-dimensional partial differential equations at steady state conditions.In order to validate the quality of the model, its results were compared with the experimental data from the field and the lab-scale ponds. The results obtained were encouraging, prediction of pond performance with measured values shows that correlation coefficients of (0.92 – 0.95) was obtained, representing an accuracy of 94%, an ultimate result that demonstrates that actual dispersion in the pond is three-dimensional. The 3-D model was then used in series of investigative studies such as; effect of single inlet and outlet structures at different positions in the pond, effect of multiple inlet and outlets on the pond’s performance, variation of pond performance with depth, effect of short-circuiting on pond treatment efficiency, effect of baffles on pond performance using laboratory-scale pond data and comparison with tracer studies. In all, the results were satisfactory.
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