Effect Of Reservoir Outflow of Hydropower Dams on The Downstream River Flood Regime: Nigeria’s Experience

Over more than five decades, the energy sector in Nigeria, particularly the rural energy sector, is characterized by lack of access, low purchasing power and over-dependence on traditional fuels for meeting basic energy needs. In an attempt by the government to solving this challenge, the hydropower scheme came on stream as the forerunner in 1968, 1986 and 1990 at Kainji, Jebba and Shiroro respectively. The objective was to improve access to reliable, secure, affordable, climate friendly and sustainable energy services and to boost investment in energy in Nigeria. Hydro Electric Power (HEP) is one of the few sources of energy that has assumed great significance since the beginning of the twentieth century. Electric power supply in Nigeria is government controlled and operated by the Power Holding Company of Nigeria (PHCN). PHCN has five thermal stations located at Afam, Delta, Egbin, Ijora and Sapele power stations and three hydropower plants located at Kainji, Jebba, and Shiroro hydropower power stations. They have installed capacities of 760 MW, 560 MW and 600 MW respectively and a total output of 1900 MW. The choice of hydro systems to generate peaking power carries a higher economic value of the water resource used and resulting in a substantial increase in the benefits realized. However, this solution seems to be characterized with some challenges at the downstream sector of the hydropower dams. The communities in the flood plains experience annual flooding when the authorities of Power Holding Company of Nigeria (PHCN) open the gates of the dams to let off water at the peak of the rains. The floods have caused damages and untold hardships to lives and property. The occurrence of flood has great effect on communities and farming activities downstream of Jebba and Shiroro dams. This paper presents an hydrological assessment, overview on reservoir effect of reservoir outflow of Kainji, Jebba and Shiroro Dam on the environment and the mitigation measures (Non-Structural and structural measures) would be reviewed.

A Review of Models for Evaluation of Climate Change Impact on Water Resources

The use of models to simulate or predict impact of climate change on water resources management is very vital due to continual increase in global warming which invariably affects most important natural resources in the environment. This paper provides an overview of the existing models used for evaluating climate change impact on water resources management. It also compares their relative advantages and drawbacks. It was found that no model can perform satisfactorily the assessment of climate change impact; hence it may be necessary to use one model to compliment the weakness of another. Global Circulation Model (GCM) is not easily accessible in developing countries due to sophistications and processes involved in running it. Moreso, the nature of available data and cost of acquiring it is high. The main advantage of Water Balance (WATBAL) model is that it can model climate change impact in water resources but its major drawback is that it requires many inputs of hydro-meteorological parameters. Regression and Artificial Neural Network (ANN) models are readily available and not too expensive. They can model climate change impact on water resources and hydropower operation. However, the drawback is that enormous data are required for ANN model calibration and operation. It is imperative therefore to anticipate and efficiently prepare for future water resources management and suggest necessary measures to mitigate the effect of climate change

Assessment of Selected Dams in Kwara State, Nigeria

In Nigeria, more than 50% of the geographical area lies in the Savannah. Over time, this area has been vulnerable to the vagaries of periodic and severe droughts, affecting the survival of man and animals. Safe and economic design and construction of dams to store surplus river waters thus assumed greater urgency. However, dam failures and flood issues has caused catastrophic damages and losses of lives and properties. The uncertainties associated with deteriorating dams have necessitated proper and timely assessment and rehabilitation of these structures. This study identifies and investigates relapse in four (4) selected dams in Kwara State namely: Unilorin-, Malete-, Okuta- Oja- and Asa-dam. A series of field inspection was carried out and results obtained were analyzed. Amongst the four dams, Okuta-Oja dam displayed the worst case of relapse with seepages through the foundation and body of the dam. About 20 baffle blocks out of 30 have been damaged in Unilorin dam, while Malete dam was undergoing re-construction owing to seepage failure. Asa dam however remains intact with no physical and structural defect. Unless appropriately handled, ageing and relapsing infrastructural systems can pose a significant problem, threatening economic prosperity and public safety. Thus, monitoring the state of dam structures to ensure timely maintenance is critically important to preventing catastrophic disasters

ASSESSMENT OF JEBBA HYDROPOWER DAM OPERATION FOR IMPROVED ENERGY PRODUCTION AND FLOOD MANAGEMENT

One of the reservoir management options for flood moderation and energy production is the operation of Hydropower Dams to protect people and their socio-economic activities in flood plain areas. This study focuses on assessing Jebba Hydropower Dam Operation for improved energy production and flood management. Available Data for 27-year period (1984 - 2011) such as inflow, elevation, turbine release, generating head, energy generation, tailrace water level and plant coefficient was obtained from Jebba Dam Station. The present reservoir-operating rule was investigated using statistical analysis to model the operation of the multi-purpose reservoir. Statistical tests carried out in accordance with standard procedure include chi-square (χ2), probability plot coefficient of correlation (r), and coefficient of determination (R2). The results show that the optimal solution at operating performance of 50% reservoir inflow reliability has the total annual energy generation of 42105.63MWH with adequate water supply for downstream users and for irrigation throughout the year with annual optimal evaporation losses averaged at 58.16Mm3. Average optimal energy generation obtained is 19% of the observed energy generation but with adequate water supply for downstream users and for irrigation throughout the year. It is, therefore, essential to develop a decision-making framework capable of handling the conflicting demand

Pengaruh Metode Question Student Have Berbantuan Media Animasi terhadap Hasil Belajar Kelas VIII SMP

The research aim to determine the effect of Question Student Have method aided media animation on student learning outcomes in material motion of plants at 2nd grade SMPN 20 Pontianak. The research design was quasi experimental design with nonequivalent control group design. This research used intact group sampling technique. Research sampel consisted of two classes which were class VIIIF as experimental class and class VIIIE as the control class. Instruments were used multiple choice tests amounted to 20 items. The average of student learning outcomes at the experimental class was 15.34, while in the control class was 14.25. Result of the U Mann-Whitney test with α=5% means there was difference on student learning outcomes was taught using Question Student Have method aided media animation and using lecture with discussion method aided media powerpoint. Effect Size value obtained 0.44 and included in the moderate category and had effect 17% on student learning outcomes

Compensated inverse PID controller for active vibration control with piezoelectric patches: modeling, simulation and implementation

Active vibration control of the first three modes of a vibrating cantilever beam using collocated piezoelectric sensor and actuator is examined in this paper. To achieve this, a model based on Euler-Bernoulli beam equation is adopted and extended to the case of three bonded piezoelectric patches that act as sensor, actuator and exciter respectively. A compensated inverse PID controller has been designed and developed to damp first three modes of vibration. Controllers have been designed for each mode and these are later combined in parallel to damp any of the three modes. Individual controller gives better reduction in sensor output for the second and third modes while the combined controller performs better for the first mode. Simulation studies are carried out using MATLAB. These results are compared and verified experimentally and the real-time implementation is carried out with xPC-target toolbox in MATLA

Identification and predictive control of spray tower system using artificial neural network and differential evolution algorithm

Increasing demands for high precision environmental protection measures regarding particulate matter (PM) emission from industrial productions and non-linear characteristics of spray tower system lead to the application of an intelligent control technique to adequately deal with these complexities. This includes the use of an artificial neural network (ANN) based predictive control strategy and differential evolution (DE) optimization algorithm to determines the optimal control signal, uk (liquid droplet size, d D ) by minimizing the cost function such that the output is set below the allowable PM concentration. A recurrent neural network (RNN) based on non-linear autoregressive with exogenous inputs (NARX) model has been used to develop the dynamic model of the system. The data for the training was obtained from empirical model of a spray tower system which involved 500 data sets representing the process input and the output PM concentration. The control process was implemented using MATLAB code by considering two DE optimization strategies; DE/best/1/bin and DE/rand/1/bin. The effectiveness of the controllers was demonstrated for different iterations by tuning the control parameters such as the prediction horizon, weight factor and control horizon. From the control response, it can be seen that the controller for the DE/rand/1/bin does a very good job of controlling the PM below the WHO allowable emission rate of 20g/μ

Bioremediating Effect of Glomus Hoi and Pseudomonas Aeruginosa on the Organic Content and Heavy Metals of Soil Polluted with Oil Refinery Effluent using Amaranthus Cruentus as a Test Plant

This study analyzed the degrading effect of Glomus hoi and Pseudomonas aeruginosa on the organic content and heavy metals of oil refinery effluent polluted soil using Amaranthus cruentus as the test plant. This study was carried out to determine if agricultural activities can be improved using any or both of the micoorganisms. Eight different treatment layouts were used with three replicates for each level of pollution in the treatment layout. Ninety six (96) pots, each containing three kilograms of soil from both sterilized and unsterilized soil were used for the study. Fifty (50) grams of soil inoculum from propagated Arbuscular mycorrhiza was inoculated to a set of twenty four (24) experimental pots containing both sterilized and unsterilized soil before A. cruentus seedlings were transplanted to them. Another set of twenty four (24) pots containing both sterilized and unsterilized soil were injected with thirty (30) mL of P. aeruginosa inoculum solution before transplanting A. cruentus seedlings to them. The third set of twenty four (24) pots received dual inoculation of both fifty (50) grams of soil inoculum containing G. hoi and thirty (30) mL of P. aeruginosa inoculum solution before A. cruentus were transplanted to them. The residual twenty four (24) pots served as the control. Thereafter, pot preparation was arranged in the screenhouse in a randomized block design. The A. cruentus seedlings were raised in nursery for a period of two weeks before they were transplanted to the pots, seedlings were left for 3 days to overcome transplanting shock before contaminating the soil with refinery effluent at various concentrations of 0%, 2%, 4% and 6% v/w. The seedlings were allowed to grow for eight weeks before the termination of the experiment. The pre planting analysis of soil showed that heavy metals analyses (zinc and iron) of sterilized soil had a lower concentration to the unsterilized. The soil pH ranged from 6.3 to 6.8. It also revealed that organic matter and organic carbon content ranged from 0.8% to 1.3% and 0.4% to 1.7%. However, after the experiment, it was discovered in this study that treatments without any microorganism inoculation in sterilized and unsterilized soil had a higher level of % organic carbon and % organic matter content compared to the other treatments that were inoculated with one or two micro-organisms across all the levels of effluent concentration. Heavy metals of soil in all the soil samples were found to increase as the petrochemical effluent increased in concentration. The results obtained were analyzed using Duncan Multiple Range Test (DMRT) and other descriptive statistics. This study opined that the combined use of G. hoi and P. aeruginosa was more effective in improving the organic contentand the reduce heavy metals of oil refinery effluent polluted soil than when either is used singly

EFFLUX MEDIATED MULTIDRUG RESISTANT PSEUDOMONAS AERUGINOSA ISOLATED FROM DIFFERENT ENVIRONMENTAL SOURCES

Pseudomonas aeruginosa is an important opportunistic pathogen and one of the leading causes of multi-drug resistant nosocomial infections. This study was therefore carried out to determine the resistance nature, and the role of efflux pump in multidrug resistance of Pseudomonas aeruginosa isolated from different environmental sources using the efflux pump inhibitor, Carbonyl Cyanide 3-Chlorophenylhydrazone (CCCP). A total of 220 environmental samples were collected and processed following standard techniques. Susceptibility to antibiotics was performed using disc diffusion methods as described by the Clinical and Laboratory Standards Institute. Activity of the efflux pump system was carried out using the efflux pump inhibitor, CCCP. Results obtained identified 100 (45.5%) Pseudomonas aeruginosa and 72 (32.7%) other strains of Pseudomonas spp. The susceptibility testing revealed that all the identified strains of Pseudomonas aeruginosa that were subjected to susceptibility test were significantly resistant to ampicillin and cefotaxime, But the  resistance profile of isolates to tetracycline, chloramphenicol, ceftriaxone, cefuroxime and perfloxacin were 93%, 72.1%, 79.1%, 58.1% and 51.2% respectively. However, imipenem was the most sensitive (100%), followed by cefepime (65%) and gentamicin (44%). Carbonyl Cyanide 3-Chlorophenylhydrazone decreased the minimum inhibitory concentration (MIC) of the isolates by 2 folds. Results obtained have shown the ubiquitous presence of multi-drug resistant P. aeruginosa from the environmental samples examined. Furthermore, it indicated the role of efflux pump in antibiotics resistance in P. aeruginosa isolates which indicate that P. aeruginosa strains from environmental sources could resist antibiotics by the efflux mechanism.     &nbsp