Water Resources Development Projects Research Articles

Experimental Investigation of Sediment Trap Efficiency in Reservoirs

Reservoir sedimentation has become one of the major problems facing water resources development projects in many countries around the world. However, only a limited number of studies has been reported in this field, particularly addressing the trap efficiency of reservoirs. In addition, whatever available studies in this area also consider few parameters governing the reservoir sedimentation. As a result, the available knowledge on trap efficiency is not very well defined. Brune curve [4] has been widely used for estimating trap efficiency of reservoirs at present, but it has several limitations, as it considers only the reservoir capacity and inflow ratio for estimating trap efficiency. The objective of this study is to formulate an improved methodology in estimating reservoir sedimentation through laboratory experiments. A small-scaled laboratory model was set-up in representing a reservoir and a series of tests were conducted by varying inflow rate, inflow sediment concentration, reservoir capacity and outflow rate. The experimental results were compared with the available theories and found that they are not very much in agreement with many of the existing theories which are mostly based on limited number of parameters. A comprehensive data analysis was performed using dimensional analysis to develop an improved relationship to estimate reservoir sedimentation incorporating many parameters governing the problem. However, the applicability of the proposed method is still limited only to the reservoirs with continuous spilling condition. In addition, only one type of sediment gradation (d50) was used in the experimental runs and thus, the effect of sediment sizes is not well represented in this method. However, the relationship developed in this study could be further improved by conducting more experimental runs by varying few other parameters which are not considered in the present study. ENGINEER, Vol. 47, No.02, pp. 1-8 2014

ENVIRONMENTAL CRITIQUE ON WATER SECTORAL ENVIRONMENTAL IMPACT ASSESSMENT OF BANGLADESH

The water resources sector of Bangladesh relies on the Environmental Impact Assessments (EIAs) to assess the possible positive and negative impacts on the e nvironmental and social components of the project affected areas. The motivation of this research was to identify the key environmental components, gaps and lapses of current EIA practices in water resources sector of Bangladesh. Under the motivation, this st udy has determined the effectiveness of a water resourc es EIA (Gorai River Restoration Project) for sustai nable implication of water resources development and management projects in Bangladesh. Component-based checklist method and effectiveness review framework were used in this study to draw conclusions and to make environmental decisions on the important secti ons of the studied EIA. Review of the key aspects a nd the analysis of the effectiveness framework disclos ed that the studied EIA is well performed and have considered sufficient information for decision maki ng, but the residual and unavoidable impacts were n ot identified for all the important environment compon ents in the construction and operation phase. Inclu sion of important environmental and social components under different intervention scenarios, consideration of alternative flow regimes, suggestions and analysis of different project interventions ensuring public participation were the key strengths of the studies EIA. The considered environmental issues and aspects of this study can be used as guidelines for the future EIAs under the similar geo-environmental contexts. The developed review framework can be implemented in water resources EIA review process to ensure longterm sustainability of water resources projects.

Current status of urinary schistosomiasis in communities around the Erinle and Eko-Ende Dams and the implications for schistosomiasis control in Nigeria

AbstractSchistosomiasis is an endemic disease in many parts of the world and the disease is associated with water resource development projects, such as dams, irrigation schemes, and rice and fish farming. The present study was designed to determine the prevalence and intensity of urinary schistosomiasis in five communities around the Erinle and Eko-Ende Dams in Osun State, Nigeria, using dipstickhaematuria, and parasitogical and molecular techniques. A total of 462 participants were screened, of whom 46.3%, 51.1% and 61.5% tested positive when using haematuria, microscopy and PCR respectively. The highest prevalence of the infection and intensity was in Illie (Erinle Dam), while Eko-Ajala (Eko-Ende Dam) had the least. Using analysis of variance and chi-square tests, the differences in the prevalence and intensity of the infection between the fve communities was statistically signifcant (p-value < 0.05). The prevalence and the intensity of the infection was higher in communities around Erinle Dam when com...

Development of a rapid environmental assessment methodology for roads sector rehabilitation projects

The concern for the environment is ever growing and counter measures are also taken by manycountries to minimize environmental impacts arising from developmental activities. One tool utilised toensure that developments are sustainable is Environmental Impact Assessment (EIA) which hasbeen a mandatory requirement in Sri Lanka since 1993. However, due to considerable time taken bythe EIA process particularly for extensive projects such as road sector projects concerns have beenraised as to the delays caused by the process which in certain instances might even cause loss offoreign funds. Although detailed assessments are required in some cases it is not always true. Roadrehabilitation projects do not fall into the category of prescribed projects of the National EnvironmentalAct unless sensitive areas are involved and resettlement of more than 100 families are involved.However, foreign funding agencies generally require an environmental assessment of even suchprojects prior to approving of funding which generally cause delays since environmental assessorstend to follow tile same pattern of assessment for all projects regardless of the scope. Numerousmethods have evolved over the years to conduct EIAs some ct'which address environmental impact assessment of sectoral projects particularly water resource development projects which are ratherconvenient to use. However thus far such methods have not been developed for road sector projects.The present study was conducted to develop a Rapid Environment Assessment (REA) technique forthe Sri Lankan road rehabilitation projects where such a tool is yet to immerge. The REA was designedfrom the information collected from literature survey, questionnaire surveys of affected communities,field observations and subject experts' interviews. Three actual rehabilitation projects were studiedfor this purpose. Based on the information first the activities relevant to all the road rehabilitationprojects were listed with the assistance received from the field engineers. Then those activities whichhave no significant impacts were taken out keeping only the activities causing impacts forconsideration.The designed tool in this study is armed with both primary and secondary impacts whichcan arise from specific activities of road rehabilitation projects as well with proposed mitigatory measureswhich can minimize these impacts. The REA is not only comprehensive but also user friendly asactivities and impacts are predetermined and linked to each other so that the users do not have toprepare their own checklists of activities or environmental aspects. It's handy and small. It's generalin usage and could be used in any site of road rehabilitation projects. It's concise as only those activitieswith significant impacts are chosen and included.From surveys it was also discovered that to avoid unnecessary oppositions and social commotion,which would hinder the rehabilitation projects compensation should be decided and granted at theplanning stage itself. It is also highly recommended that a strong monitoring system is utilized. If anyof the proposed mitigatory measures is not effective in neutralizing the impacts, a search for newmeasures is recommended and REA is to be updated accordingly. As REA is not available for roadrehabilitation projects at present in Sri Lanka the tool designed in my study could be taken for futureroad rehabilitation projects to minimize the disadvantages of ElA. However, it should note that theREA is to be used only by experts in order to be effective and accurate.

Appraisal of the Hydrological Potential of Ungauged Basin Using Morphometric Parameters

Discharge data for most basins in developing countries are lacking or inadequate where available. An alternative is to find other ways of appraising the natural water potential of basins without stream discharge records. This study attempts an appraisal of the water resource potential of the Eze-Aku basin in Ebonyi State of Nigeria using morphometric indices alone. From its morphometry the basin is essentially a low land and erosional surface. This affects both the quantity and quality of water for use by inhabitants of the basin. The analysis of results show the Eze-Aku basin is not suitable for water resources development projects demanding large monthly and annual discharge volume such as hydropower and navigation. Other morphometric parameters investigated in the study include bifurcation, shape, stream and drainage densities. Analyses of these parameters provide the basis for demonstrating the effects of environmental controls on both the basin stream network system and for predicting the basin’s output variables. Such information are essential and provide framework for improving agricultural activities, flood control and management measures and potable water supply in the study area for increased standard of living in the agricultural dominated area.Key words: Discharge, Morphometry, Water Resources Management and Planning.

An integrated study of spatial multicriteria analysis and mathematical modelling for managed aquifer recharge site suitability mapping and site ranking at Northern Gaza coastal aquifer

This paper describes an integrated approach of site suitability mapping and ranking of the most suitable sites, for the implementation of Managed Aquifer Recharge (MAR) projects, using spatial multicriteria decision analysis (SMCDA) techniques and mathematical modelling. The SMCDA procedure contains constraint mapping, site suitability analysis with criteria standardization and weighting, criteria overlay by analytical hierarchy process (AHP) combined with weighted linear combination (WLC) and ordered weighted averaging (OWA), and sensitivity analysis. The hydrogeological impacts of the selected most suitable sites were quantified by using groundwater flow and transport modelling techniques. Finally, ranking of the selected sites was done with the WLC method. The integrated approach is demonstrated by a case study in the coastal aquifer of North Gaza. Constraint mapping shows that 50% of the total study area is suitable for MAR implementation. About 25% of the total area is “very good” and 25% percent is “good” for MAR, according to the site suitability analysis. Six locations were selected and ranked against six representative decision criteria. Long term (year 2003 to year 2040) groundwater flow and transport simulations were performed to quantify the selected criteria under MAR project operation conditions at the selected sites. Finally, the suitability mapping and hydrogeological investigation recommends that the location of the existing infiltration ponds, constructed near the planned North Gaza Wastewater Treatment Plant (NGWWTP) is most suitable for MAR project implementation. This paper concludes that mathematical modelling should be combined with the SMCDA technique in order to select the best location for MAR project implementation. Besides MAR project implementation, the generalised approach can be applicable for any other water resources development project that deals with site selection and implementation.

An Anthropological Approach to HEPPs in Eastern Anatolia: The Case of Aksu Valley

Both water and development have very important functions in human life. Throughout the history, people have designed and constructed dams, reservoirs and irrigation systems to supply agricultural lands with water as well as converting water into energy as part of development projects. While water resources development projects are mostly preferred as they are cheaper and clean compared to other alternatives, impacts of such projects on people, their livelihoods and nature have been particularly devastating in many parts of the world such as Asia, Africa and Latin America. Recently, with an argument of increasing energy demand and reduction in dependence on imported energy, Turkish government has initiated some sort of “mobilization” for small hydroelectric power plants (HEPPs) to be run by private companies, particulary in the Eastern Anatolia and Black Sea regions. Despite recent initiatives, there is no established water policy in Turkey. Outsourcing control over free-flowing streams out of local representational structures into the hands of private companies has resulted in social movements and protests against these projects. I conducted a fieldwork in one of the valleys in Eastern Anatolia where two HEPPs have been constructed. Methods used during the 8-week fieldwork included participant observation, focus group studies and in-depth interviews. Privatization of the water resource in the Aksu Valley (formerly Salaçor) not only gave the entire control of water to the contractor company for 49 years, but also left all the public services in the valley to the mercy of the company while use of water has been historically well-managed by the local community, who was in control and distribution of the water. This paper discusses outcomes of the HEPP project in daily life of the local people in Aksu Valley, asserting that users of water resources should have been considered as participants in water management, planning, and decision-making of development projects. A drop of water is a sea to an ant, Afghan proverb

The Use of Satellite Images for Preliminary Investigation on Ancient Land Salt Pits in the Nam Kam River Basin, Thailand

There are numerous water resource development projects in the Nam Kam River Basin of Nakhon Phanom province in the northeastern part of Thailand. The Nam Kam River Basin is one of the Greater Mekong’s tributaries and covers an area of approximately 3,440 square kilometers. The operation of the development projects situated along the basin must be in a manner that avoids salt solution diffusing into the nearby areas and protects the existing irrigation systems and reservoirs from large amounts of salt seepage. Since saline soil, salt crusts and ancient land salt pits have been found on the ground surface of the Nam Kam Basin, the purpose of this research is to investigate the saline areas by interpreting the satellite images. The interpreted satellite images were mapped and the results were validated against the actual field data. The salinity of soil and water was measured by the electrical conductivity meter and laboratory testing. The preliminary investigation of the study area showed two groups of the saline areas: saline soil spots and ancient land salt pits. Certain difficulties remained in the interpretation of the satellite images, such as the inability to classify the degree of salinity with accuracy and the outdated data in the areas with human involvement. The saline soil spots occupied by landowners are mostly improved for agriculture; on the contrary, the ancient land salt pits are operated only by a few villagers during the summer. Even though in summer 2012, the local office of Royal Irrigation Department flooded the ancient salt pits to protect them from salt farming, the villagers continue producing salt, thereby causing salinity to spread more widely. The study reveals that monitoring of salinity of the water and soil is necessary and is currently carried out jointly by academics, the local community, and agencies responsible for the irrigation projects in the study area.

Application of ANN, Fuzzy Logic and Decision Tree Algorithms for the Development of Reservoir Operating Rules

Optimal use of scarce water resources is the prime objective for water resources development projects in the developing country like India. Optimal releases have been generally expressed as a function of reservoir state variables and hydrologic inputs by a relationship which ultimately allows the policy/water managers to determine the water to be released as a function of available information. Optimal releases were obtained by using optimal control theory with inflow series and revised reservoir characteristics such as elevation area capacity table, zero elevation level as input in this study. Operating rules for reservoir were developed as a function of demand, water level and inflow. Artificial Neural Network (ANN) with back propagation algorithm, Fuzzy Logic and decision tree algorithms such as M5 and REPTree were used for deriving the operating rules using the optimal releases for an irrigation and power supply reservoir, located in northern India. It was found that fuzzy logic model performed well compared to other soft computing techniques such as ANN, M5P and REPTree investigated in this study.

A Decision Support Tool for Stakeholder Involvement in Sustainable Water Resource Development

This paper describes the application of a decision support tool for stakeholder involvement in a proposed water resource development project in the Ma Oya river basin in Sri Lanka. The decision support tool is a five-step framework developed based on ‘Educated Trade-offs.’ The tool assesses the natural resource uses; identifies the present and future probable issues with regard to resource uses, elicit stakeholder views and then estimate the social and environmental impacts of a proposed development project. The results obtained through the application of the framework are direct inputs for stakeholder education for informed decision-making by the stakeholders. This paper highlights the stakeholder education achieved in the proposed project area and the down stream areas. The study validated the ‘Educated Trade-offs’ framework which is the decision-support tool and demonstrated its effectiveness.

Hydrological education and training needs in sub-Saharan Africa: requirements, constraints and progress

Abstract. This paper represents a perspective on the education and training needs related to hydrology and water resources science within the sub-Saharan Africa region and discusses the requirements of the region, some of the relatively recent developments and initiatives and some of the constraints that exist and remain difficult to surmount. The requirements include the development of academic research capacity and technical skill for both the private and public sector at a variety of levels. Some of the constraints that exist include a lack of adequate funding, lack of follow-up after short training courses, lack of institutional support to continue training, and competition for major water resources development projects from organizations outside the region. One of the main conclusions is that to sustain both educational and practical expertise in hydrology and water resources science within the region there is a need to build a "critical mass" of local expertise. Part of this could be achieved by increasing networking within the region and promoting the sharing of information, tools and expertise. There is also a need to promote institutional support.

Evaluation of future flow variability in ungauged basins: Validation of combined methods

Predicting future flow variability and changes in ungauged basins remains a challenging task not only because of data limitation, but also the various sources of uncertainty involved. However, for future water resources development projects, reliable estimate of future flow variability is essential. In this study, future flow variability and changes are estimated in 90 selected basins across the Province of Ontario using a multi-model approach combining bias correction and regional climate models (RCMs), downscaling and global climate models (GCMs), dual regionalization method and hydrologic model. Raw RCM outputs, bias corrected RCM data, and downscaled GCM outputs are compared to identify the most accurate predictor (precipitation, temperature) series when compared to the observed data for the current period. It is found that the bias correction approach can reduce monthly precipitation and daily temperature errors of regional climate models by about 90% and provides the most accurate precipitation and temperature time series. The bias-corrected RCM data are used with a rainfall-runoff model and a coupled regionalization method to simulate continuous streamflow in both gauged and ungauged basins. It is found that consistent streamflow and baseflow estimate can be obtained whatever the RCM data used. In general, positive (increasing) changes in streamflow are observed for all seasons except for March, April and May where negative (decreasing) trends are dominant in some basins. Future changes in baseflow are mostly positive with smaller amplitude whatever the season for almost all the 90 selected basins. Overall, it is shown that for northern, central and southern regions of Ontario, the amplitude of the variability and changes of future streamflow and baseflow in ungauged basins should be in the range of −10 to +10 mm per month based on most recent RCM simulations.

Mindset Change Needed for China’s Water Crisis

Mindset Change Needed for China’s Water Crisis

Effective watershed management; Case study of Urmia Lake, Iran

Limited water resources with uneven distribution and growing demands are the main challenges of water management in Iran. The government has planned several water resources development projects. The complex technical, socio-economical and environmental outcomes of these projects require a comprehensive evaluation. To select more adaptive and accountable projects, suitable group decision support systems are needed. In this research, 4 proposed routes of water transfer schemes to Urmia Lake in Iran, which is in danger of completely drying out, are evaluated with respect to different criteria. The criteria and weights were obtained from an organization responsible for major water infrastructures in the basin. By using an efficient multi-criteria decision making method of compromise programming, the 4 alternatives were ranked, and the most robust water transfer route was selected. This best alternative transfers about 300 million cubic meters per year from another basin in the north of the lake. Results show the importance of using decision support systems for participatory and effective lake management.

Evaluation of irrigation and drainage systems of (Southeastern Anatolia Project) GAP, the Turkey's largest integrated water resource development project

The Southeastern Anatolia Project (GAP), the Turkey’s largest integrated water resource project, is among the world’s most important regional development projects in terms of numeric size and influence. In the present study, irrigation systems and drainage requirements within the scope of GAP in the Euphrates and Tigris Basins are investigated. With the data collected, an attempt was made to determine the potential operational problems in terms of present requirements by investigating water resources, irrigation systems, and water distribution methods, efficient use of water control structures, valves, and water, and drainage requirements and systems based on field observations. In order to solve these problems and ensure that similar problems are not experienced in future projects, recommendations related to needs are made on subjects such as management and operation models that will achieve optimum use of resources, institutional and legal contents, social and cultural behaviors, environmental interaction potential, and economic requirements. A summary of wide-ranging research carried out in the study area, problems and recommendations are presented together. Key words: GAP region, water resources, irrigation systems, drainage.

Deliberation and Scale in Mekong Region Water Governance

Understanding the politics of deliberation, scales, and levels is crucial to understanding the social complexity of water-related governance. Deliberative processes might complement and inform more conventional representational and bureaucratic approaches to planning and decision-making. However, they are also subject to scale and level politics, which can confound institutionalized decision-making. Scale and level contests arise in dialogues and related arenas because different actors privilege particular temporal or spatial scales and levels in their analysis, arguments, and responses. Scale contests might include whether to privilege administrative, hydrological, ecosystem, or economic boundaries. Level contests might include whether to privilege the subdistrict or the province, the tributary watershed or the international river basin, a river or a biogeographic region, and the local or the regional economy. In the Mekong Region there is a recurrent demand for water resources development projects and major policies proposed by governments and investors to be scrutinized in public. Deliberative forms of engagement are potentially very helpful because they encourage supporters and critics to articulate assumptions and reasoning about the different opportunities and risks associated with alternative options, and in doing so, they often traverse and enable higher-quality conversations within and across scales and within and between levels. Six case studies from the Mekong Region are examined. We find evidence that scale and level politics affects the context, process, content, and outcomes of deliberative engagement in a region where public deliberation is still far from being a norm, particularly where there are sensitive and far-reaching choices to be made about water use and energy production.

History of Water Management in Japan from the End of World War II

The history of Japan after the Second World War is a dramatic story, which ranges from miserable poverty to an economic prosperity that reached a surprisingly high economic level, but is now suffering from a difficult downturn. To cope with the changing socio-economic transformation over 60 years, water management has also undergone a radical development, with large-scale river projects for flood control, water resources development and environmental measures. The Japanese experience would benefit current developing countries, especially Asian monsoon countries, because they are now actively developing flood control measures, water resources development projects and also conservation work.

Modeling Monthly Mean Flow in a Poorly Gauged Basin by Fuzzy Logic

AbstractThe estimation of the monthly mean flow is a critical issue in many water resource development projects. However, in practice the mean flow is not easily determined in ungauged and poorly gauged basins. Therefore, in the literature, various flow estimation methods have been developed recently for mountainous regions which are generally ungauged or poorly gauged basins. In this study a fuzzy logic model based on the Mamdani approach was developed to estimate the flow for poorly gauged mountainous basins. This model was applied to the Solakli Basin which is located in the Eastern Black Sea Region of Turkey. Limited rainfall and flow data are available for this basin. In addition to these variables, the stream and time coefficients were introduced and used as variables for modeling. The data was divided into training and testing phases. The model results were compared with the measured data. The comparison depends on seven statistical characteristics, four different error modes and the contour map method. It was observed that the fuzzy model developed in this study yielded reliable results.

STAKEHOLDERS, SPATIAL LOCATIONS AND TIME HORIZONS IN AN EXTENDED SOCIAL COST-BENEFIT ANALYSIS: A CASE OF PIPALPANKHA WATER RESOURCE PROJECT

Cost-Benefit Analysis (CBA) has been serving as an important tool for decision making with regard to the development projects involving large investments. The Social Cost-Benefit Analysis (SCBA) is an extension of the CBA to certain social impacts, which hitherto were not measured. As the impacts of development projects on ecology and environment assumed importance, measuring the corresponding costs and benefits also began to assume significance. With the advancement in economic valuation techniques over time, measurement could be done and the framework of SCBA has been extended to incorporate the same. Moreover, unlike the CBAs, which do not account for the distributional aspects, the SCBA can potentially account for these. This paper presents a case study of extending the SCBA framework to include social and environmental impacts of a large water resource development project in India. It emphasises the distribution of project benefits and costs over stakeholders, spatial locations and time horizons so as to demonstrate the utility of extended SCBA in project decision making. It is observed that both the numeraire measure i.e. cost-benefit ratio, as well as the distributional analysis present a favourable case for the project.

Malaria and water resource development: the case of Gilgel-Gibe hydroelectric dam in Ethiopia

BackgroundEthiopia plans to increase its electricity power supply by five-fold over the next five years to fulfill the needs of its people and support the economic growth based on large hydropower dams. Building large dams for hydropower generation may increase the transmission of malaria since they transform ecosystems and create new vector breeding habitats. The aim of this study was to assess the effects of Gilgel-Gibe hydroelectric dam in Ethiopia on malaria transmission and changing levels of prevalence in children.MethodsA cross-sectional, community-based study was carried out between October and December 2005 in Jimma Zone, south-western Ethiopia, among children under 10 years of age living in three 'at-risk' villages (within 3 km from dam) and three 'control' villages (5 to 8 km from dam). The man-made Gilgel-Gibe dam is operating since 2004. Households with children less than 10 years of age were selected and children from the selected households were sampled from all the six villages. This included 1,081 children from 'at-risk' villages and 774 children from 'control' villages. Blood samples collected from children using finger prick were examined microscopically to determine malaria prevalence, density of parasitaemia and identify malarial parasite species.ResultsOverall 1,855 children (905 girls and 950 boys) were surveyed. A total of 194 (10.5%) children were positive for malaria, of which, 117 (60.3%) for Plasmodium vivax, 76 (39.2%) for Plasmodium falciparum and one (0.5%) for both P. vivax and P. falciparum. A multivariate design-based analysis indicated that, while controlling for age, sex and time of data collection, children who resided in 'at-risk' villages close to the dam were more likely to have P. vivax infection than children who resided farther away (odds ratio (OR) = 1.63, 95% CI = 1.15, 2.32) and showed a higher OR to have P. falciparum infection than children who resided in 'control' villages, but this was not significant (OR = 2.40, 95% CI = 0.84, 6.88). A classification tree revealed insights in the importance of the dam as a risk factor for malaria. Assuming that the relationship between the dam and malaria is causal, 43% of the malaria occurring in children was due to living in close proximity to the dam.ConclusionThis study indicates that children living in close proximity to a man-made reservoir in Ethiopia are at higher risk of malaria compared to those living farther away. It is recommended that sound prevention and control programme be designed and implemented around the reservoir to reduce the prevalence of malaria. In this respect, in localities near large dams, health impact assessment through periodic survey of potential vectors and periodic medical screening is warranted. Moreover, strategies to mitigate predicted negative health outcomes should be integral parts in the preparation, construction and operational phases of future water resource development and management projects.