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The main thrust of this book is focused on addressing the various interrelated processes, analysis and activities bearing upon sound river management. River basins are complex systems. They are open systems with sometimes ill-defined boundaries. It refers to various aspects essential to achieve a sustainable development of river basins, including water demand and river management. Intensified erosion, land water degradation and stream flow pollution which call for appropriate river restoration and training measures. A viable theory for river management must reconcile the various processes that occur at different scales in order to develop a knowledge base by synthesizing research and field studies results. The book is intended to augment the knowledge base of behaviour of rivers and analyse the issues related to rivers so as to develop river system management techniques emerging from in-depth scientific analysis as a priority. This book pools together the expertise, the in-depth knowledge and the experience of the people representing different disciplines bearing on the related aspects of analysis and management of river systems.

Audience

The book is expected to be useful to academics, practitioners, scientists, water managers, environmentalists, administrators, researchers and students who are involved and have stakes in water management and river system analysis.

Inhaltsverzeichnis

Frontmatter

1. Introduction

Water is required to ensure food security, feed livestock, and industrial production and to conserve the environment. Human population has always been dependent on the rivers for survival. Management of rivers has been attempted by humans since the ancient times as the civilizations developed in the vicinity of the rivers. As the world’s population grows, the demand for water mounts and pressure on finite water resources intensifies. But the importance of population is major factor to consider. However, the brutal challenge of climate change resulting in changes in rainfall regimes, threatening surface as well as groundwater, contributes to making water resource scarcity a reality. Changes in hydrological cycle will certainly alter the precipitation and evapo-transpiration patterns, resulting in significant changes in the discharge regime of rivers. Moreover, it may lead to greater unreliability of dry season flows that possess potentially serious risks to water and energy supplies in the lean season. Therefore, before planning and management of any long-term water resources, the assessment of climate change impacts on the hydrological resources is of prime importance. The two main policy responses to climate change are mitigation and adaptation which is necessary to deal with the impacts of climate change. Adaptation measures may be planned in advance or put in place spontaneously in response to a local pressure. Incidences of waterrelated disasters are showing an upward trend due to climate change impacts thereby increasing the frequency and intensity of extreme weather. These issues intensify the phenomenon of erosion, land–water degradation, and pollution which demand for river restoration and training, as rivers are the essential element for sediment transport from surface land to oceans. The complexity of implementing the Integrated Land and Water Resources Management (ILWRM) increases manifold when the river crosses political border, thus making it a transboundary in nature which are not regulated by ratified international laws. Hence the need for transboundary international water law is overwhelming, constant, and immediate.
Nayan Sharma, Subash Prasad Rai, Dheeraj Kumar, Harinarayan Tiwari

Sediment Transport

Frontmatter

2. Forest Impact on Flood Peak Discharge and Sediment Yield in Streamflow

Two recent studies help to define the extent to which forest cover, compared with a cover of shorter vegetation, can reduce flood peaks and sediment yields at the catchment scale as part of an integrated flood control programme. First, field data analysis and model analysis tested the hypothesis that, as the size of the rainfall event increases, the effect of forest cover on peak discharge becomes less important. Second, a systematic model analysis assessed the relationship between specific sediment yield and catchment area for various land use scenarios. The results show that the change in forest cover must apply to 20–30 % of the catchment area to affect the hydrological response; forest cover can affect the peak discharges for small to moderate floods but has little effect on large floods; increased cultivation in headwater areas can increase sediment yield, but the effect becomes attenuated over an order of magnitude increase in catchment area. In an Indian context, these results suggest that altered land use in the Himalayas has little immediate effect on flood magnitude and sediment yield in Bangladesh. However, forests can have a role in controlling floods and sediment yield in smaller headwater catchments.
James C. Bathurst, Steve J. Birkinshaw, Felipe Cisneros Espinosa, Andrés Iroumé

3. On the Physical and Operational Rationality of Data-Driven Models for Suspended Sediment Prediction in Rivers

Suspended sediment remains an important variable for prediction in river studies. Knowledge of suspended sediment concentration or load at different downstream locations within a channel allows the temporal and spatial patterns of catchment sediment yield to be determined, as well as within-channel sediment budgets that provide important insight into the patterns and processes governing channel siltation and scour. However, in many rivers, the comprehensive and long-term downstream monitoring of discharge contrasts with relatively sparse and temporally discontinuous monitoring of suspended sediment. As a result, the generation of suspended sediment data through physical and empirical modelling approaches is commonplace. The emergence of a data-driven modelling paradigm in the last two decades has resulted in the adoption of new methods for suspended sediment modelling. To a large extent, these methods mirror traditional empirical approaches, except that the a priori determination of the form of the response function by the modeller is replaced by machine learning and artificial intelligence algorithms that ‘learn’ the response function (both its form and associated parameters) directly from data. Data-driven models have been shown to result in improved goodness-of-fit metric scores, but many hydrologists remain critical about the lack of attempts by data-driven modellers to demonstrate the physical rationality and operational validity of their models. In this chapter, we examine this criticism; highlight specific research challenges facing data-driven, suspended sediment modellers; and detail the research directions through which advances may be made.
Nick J. Mount, Robert J. Abrahart, Christian W. Dawson

4. Sediment Dynamics in a Large Alluvial River: Characterization of Materials and Processes and Management Challenges

Sediments of a large alluvial river often hold the key to its geoenvironmental behavior. Several physical and chemical behaviours of high sediment carrying river including water quality, bank line shifting, sediment budget and bank erosion are influenced by sediments. The current study carries out a partial evaluation on some of the key factors. Considering severity of bank erosion problem in the last few years, six locations on the river Brahmaputra were considered for this study. Role of individual bank material properties in bank erosion were studied with binary logistic regression using SPSS.
Young lithology, seismicity, unconsolidated sedimentary rocks of the Himalayas, steep slope of the Brahmaputra in the Himalayas, heavy rainfall in monsoon, deforestation and Jhum cultivation were the causes of sediment generation in the river, whereas decrease of slope in Assam plains was the main cause of sediment deposition. Steepness of the Brahmaputra River is high compared to most of the large rivers of the world including Amazon, Congo, Yangtze, Volga, Mississippi, Ganges and Indus. Slope of the Brahmaputra River created by using data of 175 points along the channel taken from GoogleEarth demonstrated a much clear picture with marked differences compared to the earlier figure based on a few points proposed by other researcher.
Erosion was more severe in the south bank whereas more deposition is taking place in the north bank of the Brahmaputra, particularly in upstream of Dibrugarh. Erosion during 1990–2008 in north bank and south bank of the Brahmaputra (within Assam) were 544 km2 and 920 km2 respectively, whereas corresponding deposition were 145 km2 and 68 km2 respectively.
An attempt was made to construct a sediment budget for the Brahmaputra River in Assam using a mass balance equation. Major tributaries were found to contribute 326 × 106 t suspended sediment in a year to the Brahmaputra. Considering 30 % of riverine sediments trapped in the river beds and flood-plains, 228 × 106 t sediments were considered in suspension at downstream, whereas 98 × 106 t was estimated to be deposited. From scouring and deposition data, mass of deposited sediment on river bed has been 69 × 106 t in a year. Area of land lost due to bank erosion in a year was found to be 81 × 106 m2. Total sediment load in the river at downstream was estimated 869 × 106 t/year. Considering 10 % of sediment load of the Brahmaputra as bed load, suspended sediment load at downstream was 782 ×3 106 t/year. Tributaries, bank erosion and scouring of river bed were found to contribute 26 %, 54 % and 20 % to suspended load of the Brahmaputra at downstream. The findings differed somewhat from previous estimates possibly due to relatively dependable volume of currently measured data.
Among the analysed parameters pH, OC, CC, CEC, ESP, d10, d50 and d90, were more fluctuating in bank materials of erosion sites than that of non-erosion sites. Low (<2 %) organic content, dominance of silt and sand sized particles, particularly in lower layer of sediment profile were the major geochemical properties of bank materials contributing to bank erosion in sites like A, B, E and F. Decrease of SAR, ESP and CEC towards deeper depth showed similarity to results of other erodible areas elsewhere. Presence of clay pocket and high organic content at lower layer of sediment profile had no role in stability of bank profile in C area due to overall dominance of silt particles in the bank.
The present study has the potential scope of study of fate and transport of sediments of a large alluvial river using more data from tributaries as well as the main stem. Inclusion of hydrological parameters can led to reliable erosion prediction in a particular area. Consideration of bank material properties and erosion behavior can be effective in site specific protection measures of erosion problem.
Chandan Mahanta, Lalit Saikia

5. Sediment Runoff Modelling Using ANNs in an Eastern Himalayan Basin, India

The amount of sediments transported by headwater rivers plays a crucial role in planning of water resources. Most widely used methods of estimating the sediment in rivers are the empirical methods, and in India, the rating curve technique is most popular. The present study is focused on the application of artificial neural network (ANN) technique for sediment-discharge modelling of a headwater river. For ANN development, daily discharge and suspended sediment concentration data of Subansiri River (an eastern Himalayan river) in India have been used. Rating curves have also been developed with similar data, and comparison of the two techniques has been carried out. It has been observed that the estimates of suspended sediment concentration obtained by ANNs compared to the rating curve technique were much closer to the observed values.
Archana Sarkar, Nayan Sharma, R. D. Singh

Land Use and Climate

Frontmatter

6. River Basin Impact Assessment of Changing Land Use and Climate by Applying the ILWRM Approach in Africa and Asia

Methodological aspects of scale-related impact assessment from changing land use/land cover (LULC) management and climate on river basin water resources and their management are discussed. Both control the interactive hydrological process dynamics that transfer precipitation input on the landscape to the different surface and subsurface water resources components and ultimately to river runoff draining the river basin. As the integrated water resources management (IWRM) concept does not sufficiently account for the landscape-related process dynamics associated with LULC management, it is enhanced to the integrated land and water resources management (ILWRM) approach. The latter requires, firstly, a consistent methodological concept and, secondly, a toolset for its implementation. The DPSIR (D = Drivers, P = Pressures, S = State, I = Impacts, R = Responses) approach is a suitable analysis concept in this regard and is enhanced by a Decision Information Knowledge System (DIKS). Both are implemented by means of the integrated land management system (ILMS) toolset developed at the University of Jena, Germany, and tested in numerous research projects in Africa, Asia, Australia, Europe and South America. The majority of river catchment studies focus on a particular scale. Upscaling and downscaling of the hydrological knowledge they generate requires the separation of the generic knowledge components from their modifying local specifications. The interdisciplinary ILWRM applications presented in this paper from two projects in South Africa and SE Asia address this challenge by applying a multi-scale nested catchment approach (NCA) and respective upscaling and downscaling techniques to regionalize hydrological knowledge between scales.
Wolfgang-Albert Flügel

7. Analysis of Climate Variability in a Part of Brahmaputra River Basin in India

Regional specific study of the most important climatic variables is essential to reduce the adverse effects of climate change in developing countries. In the present study, an attempt has been made to detect the trends in rainfall and temperature (past and future) time series and the possibility of any rational relationship between the trends and elevation over study region. The study was mainly focused on a part of Brahmaputra river basin in Northeast India, i.e., the Dikhow catchment (area = 3100 km2). The Dikhow catchment is a set of unique composite catchment topography comprising fairly higher altitude hills as well as alluvial plains at much lower elevation. Historically (from the year 1901 to 2002), annual precipitation and monsoon precipitation are decreasing significantly (5 % level of significance), whereas significant rise was observed on annual and seasonal basis for both maximum and minimum temperature time series. Further, during the entire time series (1901–2002), significant negative correlation was obtained between precipitation (annual and monsoon) trend magnitude and elevation of the study region. Significant rise for future precipitation was identified over the region for both A2 and B2 SRES scenarios, and winter precipitation is likely to increase more (59.18–69.44 % under A2 and 47.71–54.90 % under B2 over the catchment) than summer and monsoon precipitation. The maximum temperature has higher rate of rise than the minimum temperature for annual, summer, and monsoon temperature time series, while winter season shows higher rate of rise rather than the maximum temperature (1.02 °C over 102 years). For diurnal temperature range (DTR), monsoon season shows the significant rising which varies from 0.0016 to 0.0021 °C/year. Extreme temperature indices (TXx, TXn, TNx, and TNn) also show the significant warming picture over the catchment. Trend magnitude of extreme temperature indices and elevation shows significant relationship, while trend magnitude of the average maximum and minimum temperature and DTR does not show the noticeable connection between warming rate and elevation of the study area. Future Tmax and Tmin are increasing sharply for both A2 and B2 scenarios. A2 scenario shows higher rate than the B2 scenario.
Pratibha Warwade, Nayan Sharma, Ashish Pandey, Bodo Ahrens

River Hydraulics

Frontmatter

8. Local Scour

Flow in a channel with a mobile bed is usually accompanied by a transport of sediments; erosion and deposition might be the consequence. Additional erosion of sediments will be caused, where there is a local change in the geometry of the channel or in the flow.
Different kinds of local scour are encountered in fluvial hydraulics. Positioned in the flow, a pier or an abutment will locally alter the flow and cause erosion (deposition) in the vicinity of the obstacle. Constriction scour is encountered, if the width of a channel is reduced. Flow over and/or under a hydraulic structure has a considerable potential to cause scour at the downstream.
Walter H. Graf, Mustafa S. Altinakar

9. Emerging Methodologies for Turbulence Characterization in River Dynamics Study

River engineering study consists of large variation in time and spatial scales. Timescale of river varies from years to second, and, similarly, the variation of spatial scales is from kilometre to millimetre. Spatial scales can be divided into river basin scale and hydraulic scale, and temporal scale can be divided into hydrological, hydraulic and turbulence. Each spatio-temporal scale has fixed contextual uses. In general, turbulence plays the most key role with respect to the influences that rivers have on their channels and beds. Turbulent flows are characterized by asymmetrical patterns, irregular behaviour and the existence of various spatio-temporal scales. To extract better turbulence events and flow structure using point velocity measurements (Eulerian approach) in river, we are proposing generalized three-dimensional octant events instead of conventional two-dimensional quadrant events. Beyond that, we characterize the transitional probability of octant event occurrence in the case of unsteady flow condition. In the field, there is the assumption of steadiness of the flow under high unsteady conditions. Basically, river discharges and all the associated processes are physically unsteady, and river channel flows are typically non-uniform. In this chapter we are mainly discussing the new emerging methodological aspects to characterize the river turbulence using state-of-the-art technology. In this chapter, some of the major issues and developments linked with river dynamics and turbulence study have also been discussed with two case studies. The case studies have been presented and discussed using experimental data and their interpretation in light of river dynamics. The study has significant importance because the turbulent motion is the natural state of river engineering problems.
Harinarayan Tiwari, Amir Khan, Nayan Sharma

River Modelling

Frontmatter

10. Prospects of Modeling and Morpho-dynamic Study for Brahmaputra River

The Brahmaputra River in the Northeastern State of Assam in India is characterized by its exceedingly high discharge with enormous sediment load, spatio-temporal variation in channel morphology, substantially high bed aggradations, and severe bank line erosion. The river maintains almost continuous channel braiding in most of its segments in the alluvial floodplains of Assam. One-dimensional (1-D) flow models are insufficient to tackle problems of braided streams due to lack of information with regard to transverse flow field. Hence, for better and more realistic flow field assessment, two-dimensional (2-D) or three-dimensional (3-D) numerical models are to be used. 3-D models are numerically too expensive for macro scale river reaches. Hence, 2-D enhanced model with secondary flow corrections in governing equations may be used. After successful implementation of 1-D mathematical model for a braided stretch of Brahmaputra River, 2-D enhanced numerical model with boundary-fitted coordinate system for the same stretch has been developed and verified. A new planform index is proposed namely braid power. It increases with decrease in incoming discharge into the reach in a particular instance of time. The measured braiding indicator, namely, Plan Form Index (PFI) using high-resolution satellite data application, is found to be quite useful for the monitoring and analysis of persistent and complex braiding behavior of a large river like the Brahmaputra. The erosion study based on satellite data based analysis conclusively identifies three to four major geological channel nodal points present along the Brahmaputra River. The variability of stream power with bank erosion and braiding process is investigated. A distinct behavioral pattern between these is observed. For example, with low stream power, braiding appears to intensify which in result may reflect a higher possibility of bank erosion.
Nayan Sharma, M. P. Akhtar

11. Development of a Fuzzy Flood Forecasting Model for Downstream of Hirakud Reservoir of Mahanadi Basin, India

Floods occurring at delta of Mahanadi are mostly due to contribution of downstream catchment of Hirakud reservoir of Mahanadi basin. Controlling flood through other structural measures is inadequate and difficult. The downstream part is devoid of a sound flood forecasting method. In order to protect the life and property, a nonstructural measure like a workable flood forecasting model is needed to mitigate the destruction at delta by enhancing appropriate and timely relief measures. Establishment of a physical base model requires a lot of meteorological and physical information of the catchment. When such detailed information or data are not available, an alternative method based on soft computing technique may play an important role. Therefore, in this paper, a soft computing-based flood forecasting model using fuzzy inference system is attempted at Mundali station in Mahanadi river and the results compared with observed values. The input and output peaks are grouped into low, medium, high, medium high, and very high categories and operated by nine fuzzy rules.
The discharge at Mundali (forecasting station or FS) is forecasted using the discharge of Khairmal (base station or BS) and Barmul (intermediate station or IS) gauge and discharge sites. The base station is 115 km downstream of Hirakud reservoir and forecasting station is just before starting of delta zone. Forecasting stations are 200 km away from the base station. Peak discharges of 10 years (2001–2010) are considered as input to the model. The output of the model is encouraging with good efficiency and lower RMSE values. The travel time has been finalized adopting clustering techniques, thereby differentiating as per five types of peaks. The model gives better forecasting for high peaks rather than medium and low peaks.
Anil Kumar Kar, Anil Kumar Lohani, N. K. Goel, G. P. Roy

12. Distributed Hydrological Modelling Under Hypothetical Climate Change Scenario for a Sub-basin of the Brahmaputra River

A process-oriented hydrological model J2000 was employed on daily and monthly time steps for run-off simulation under Indian condition for the years 2003–2010. Further, a validated model was used for water balance assessment of the basin under both present scenario and hypothetical variations in precipitation and temperature. The regional sensitivity analysis (RSA) approach was employed for sensitivity analysis to determine the critical input parameter of the study area. It is inferred that recession coefficient for overland flow (soilConcRD1) is the most sensitive parameter, followed by recession coefficient for interflow (soilConcRD2) and linear reduction coefficient for AET (soilLinRed). Four evaluation criteria, i.e. coefficient of correlation (R), Nash-Sutcliffe efficiency (NSE), percent bias (PBIAS) and root-mean-square error (RMSE) observation standard deviation ratio (RSR), were adopted, for judging the model’s performance. For daily time steps, the PBIAS, R, NSE and RSR were found to be 4.73, 0.85, 0.67 and 0.45, respectively, during calibration and −1.50, 0.92, 0.85 and 0.29, respectively, during validation of the model. For monthly time steps, the PBIAS, R, NSE and RSR were found to be 4.73, 0.88, 0.7 and 0.43, respectively, during calibration and −1.50, 0.94, 0.89 and 0.26, respectively, during validation of the model. Further, model-simulated run-off components are overland flow (RD1), model’s interflow components (RD2 and RG1) and baseflow component (RG2), and the percent contribution was found to be 43.1 %, 35.8 % and 21.1 %, respectively. The water balance analysis carried out in the study demonstrated that the annual average precipitation in the basin is about 1,388 mm, out of which about 21 % flows out as run-off, 22 % as groundwater and about 56 % as evapotranspiration. The higher value of evaluation criteria indicates that the model is efficient in imitating the hydrological phenomenon of the Kopili River basin fairly well and can be cogitated as a promising tool to understand the constantly changing hydrological processes of Northeast (NE) India. Moreover, the hypothetical temperature increases due to the lowest emission scenario (1.1–2.9 °C), and the highest emission scenario (2.4–6.4 °C) of the IPCC (Climate change 2007: the physical science basis. Contribution of working group I. In: Solomon S, Qin D, Manning M, Chen Z, Marquis M, Averyt KB, Tignor M, Miller HL (eds) Fourth assessment report of the intergovernmental panel on climate change. Cambridge University Press, Cambridge, UK, 2007) indicates that the higher evapotranspiration is mainly resulting in low surface run-off and groundwater contribution. The run-off fluctuations resulting from ±10 % variation in precipitation were also analysed and were found to be approx. ±18 % deviation from simulated run-off. This analysis will be useful to understand the verge of hydrological processes in anticipation of global climate change (CC) and finally for sustainable water resource management in the NE region of India.
Dheeraj Kumar, Ashish Pandey, Wolfgang-Albert Flügel, Nayan Sharma

River Training

Frontmatter

13. River Management with Submerged Vanes

Submerged vanes are an unobtrusive and cost-effective way for river engineers to address many problems associated with river management. The vanes are small flow-training structures designed and installed on the riverbed to modify the near-bed flow pattern and redistribute flow and sediment transport within the channel cross section. The structures are laid out so they create and maintain a flow and bed topography that is consistent with that of a stable channel creating optimum conditions for managing the river. A relatively new technology, submerged vanes are a low-impact method for restoring river banks, stabilizing or re-meandering river reaches previously modified (straightened) by humans, increasing flood flow capacity, reducing sediment deposits, and helping maintain or enhance the ecosystem in and around rivers. Following laboratory research and feedback from field installations, guidelines are now available for designs that are effective and sustainable. The experience summarized herein suggests that vanes are an attractive technology for managing streams of all sizes ranging from small creeks to large, braided rivers like Brahmaputra.
A. Jacob Odgaard

14. Behaviour and Training of River Near Bridges and Barrages: Some Case Studies

Large numbers of bridges and barrages are being constructed across innumerable rivers in India and abroad to serve different purposes for the benefit of the people. It is important to understand the river behaviour before and after the construction of bridges and barrages for their proper planning, design, construction, operation and maintenance. Costly protective measures are often needed to train the river against uncontrolled scouring, silting, meandering, anabranching and many other problems for the safety of the structures as well as the approach and marginal/afflux embankments. Breaching of embankments, outflanking of the structures, river avulsion, etc. cause disruption of traffic, unprecedented damages and unimaginable sufferings of the people and often defeat the very purpose of the structures. In this paper, the author has discussed with figures and photographs about the morphological changes that were found to occur upstream and downstream of some bridges and a barrage and the protective measures adopted to train the rivers in the Himalayan region of India.
S. K. Mazumder

15. Design Development and Field Application of RCC Jack Jetty and Trail Dykes for River Training

While river training structures are important tools to provide solutions to river engineering problems, conventional structures can be expensive and can create adverse environmental impacts. There is a need to develop affordable permeable river training structures. Jack jetties have been in use in the USA for various purposes, although there was no scientific methodology to support design of the structures when used for river training works. Therefore, laboratory studies have been carried out to develop this design methodology, which was verified by field-testing. Trail dykes were also tested in a similar fashion. Both types of structures show promise for use as inexpensive river engineering works.
Anupama Nayak, Nayan Sharma, Kerry Anne Mazurek, Alok Kumar

16. Kusaha Breach Closure of Kosi River: A Case Study

The eastern afflux bundh upstream of Kosi Barrage situated at Bhimnagar in Nepal near Birpur in India got breached at Kusaha (Nepal) on 18 August 2008. The Kosi floodwater gushed out to the countryside and caused large-scale devastation lower down in one district of Nepal and five districts of Bihar. A population of about 3.3 million in India (Bihar) and 100,000 in Nepal got flood inundated. They suffered extreme damages to their lives, properties and standing crops. About 500 persons lost their lives. Important infrastructures such as railways, eastern Kosi canal systems, roads, electric transmission lines, public and private tube wells, lift and surface minor irrigation schemes, public and private buildings, etc. got severely damaged. On a rough estimate, the colossal damage to properties was of the order of about Rs. 15,000 crores. Thus, it was one of the biggest tragedies due to flood fury in the recent history.
After the breach, discharge of the Kosi approaching the Barrage about 13 km downstream became almost negligible, and the entire river avulsed into a new course through various old abandoned streams (dhars) of the river.
The gigantic task of bringing the river back to the original course was taken up on war footing, and 1.73 km-wide breach was finally closed on 30 January 2009. The allied flood protection works such as spurs, bedbars, slope, apron pitching, etc. were also completed by 1 May 2009. Thus, the Kosi River was again brought back to flow along its established course through the Barrage.
The story of this nature’s fury versus human grit which has been acclaimed as one of the most challenging engineering endeavours of our time has been described in this paper as a case study.
D. P. Singh

Water Quality and Ecology

Frontmatter

17. Preliminary Assessment and Attempt to Maintain Minimum Ecological Flows in Upper and Middle Ganga River

The impact of releasing additional water from Tehri Dam (114 m3/s), and subsequent releases downstream barrages at Bhimgoda, Bijnor, Ramganga feeder canal (from Kalagarh Dam on Ramganga River), and Narora Barrage (71 m3/s) particularly during Kumbh bath festival for cultural/spiritual/ecological reasons during lean flow months (December–March) to augment river flows at Har ki Pauri (Hardwar) and at Sangam (Allahabad before confluence of Ganga with Yamuna River) at the cost of irrigation water seems to be unattractive due to negative water balance during non-monsoon period between Hardwar downstream catchment and Allahabad. The better option to raise water level at Sangam appears to be closing of lift pump canals situated between Kanpur and Raebareli (34 m3/s) and escaping Sharda Sahayak canal water (11 m3/s) from Bhadri escape into the Ganga River 40 km upstream of Allahabad. The other option may be construction of barrages at suitable places – Chhatnag (d/s Sangam nose, Allahabad), Kalakankar (Pratapgarh), and Bhitaura (Fatehpur) – to augment 64 m3/s water at 75 % dependability to maintain water depth 1.2 m at Sangam. Dredging of the active channel may provide adequate depth of water for bathing and navigation.
The combined effect of low flow and discharge of polluting effluent into the Ganga has caused severe deterioration in the quality of water, sediment, and aquatic biodiversity in the river. But the Ganges’ pollution and low flow issues are two entirely different things. Similarly, trade-off between food security and river ecological services has to be decided on objectives of the society. The preliminary assessment of environmental flows (EFs) for the Upper Ganga basin by WWF-India (2012 assessment of environmental flows for the Upper Ganga Basin, HSBC Water Programe) at Kaudiyala (rafting site 30 km u/s Rishikesh), Kachla bridge (d/s Narora), and Bithoor (u/s Kanpur Lav Kush barrage) suggests 72 %, 45 %, and 47 % MAR natural, respectively, using building block methodology (BBM). This study further needs refinement based on actual flow regimes.
Ravindra Kumar

Transboundary River Issues

Frontmatter

18. Opportunities and Challenges in the Trans-boundary Koshi River Basin

The Koshi river basin is shared between China, Nepal and India and is one of the key trans-boundary river basins in the Hindu-Kush Himalayas (HKH). The basin drains an area of about 88,000 km2 and is a river system with a high potential for investments in hydropower development as well as irrigation in the downstream areas. In addition the basin contains important ecosystems and protected areas which provide a range of biodiversity and related ecosystem services and sustain livelihoods. The basin is home to over 40 million people with agriculture as the dominant activity. However, the diverse topography, young geological formations, degree of glaciation and monsoon system make the basin particularly prone to water-related hazards like extreme flooding and landslides. Droughts are also experienced in the rain-fed tributaries of the basin during the dry season. Urbanisation and floodplain encroachment have also added pressures on the water bodies and ecosystems of the basin. Climate change will likely exacerbate these pressures with consequences for seasonal water availability, and food and energy security, highlighting the need for appropriate water management and disaster risk reduction strategies. A river basin approach, through the application of integrated water resources management (IWRM) principles, is essential to address the trans-boundary nature of many of these multifaceted issues. A conceptual framework for addressing these challenges within an integrated water and land resources management perspective for the Koshi basin is presented in this paper.
Shahriar M. Wahid, Garrett Kilroy, Arun B. Shrestha, Sagar Ratna Bajracharya, Kiran Hunzai

19. Hydropolitics in Transboundary Water Conflict and Cooperation

Water is a fundamental human need and key to economic development. Since the beginning of civilization, people have faced problems associated with river and freshwater sharing. To add on to the precarious situation, most of the freshwater rivers are transboundary rivers, i.e. they cross at least one political border, either a border within a nation or an international boundary. Water politics, commonly known as hydropolitics, are politics affected by the availability of water and water resources, which play an important role in transboundary water management. Hydropolitics relate to the ability of geopolitical institutions to manage shared water resources in a politically sustainable manner, i.e. without tensions or conflict between political entities. As the pressures of population and economic growth increase, water resources are under increasing stress. As the stress on water resources increases, the risks associated with the management of transboundary rivers increase exponentially given the hegemonic disparities of the riparians. This gives rise to risks of conflict while generating opportunities of cooperation which can be analysed with the help of risk-opportunity index developed using fuzzy synthetic evaluation technique proposed by Rai et al. (J Hydrol 519:1551–1559, 2014). It has been proposed to formulate a hydropolitical sustainability index (HypSI) keeping in view the circles of blue sustainability (blue indicates water in this chapter) which considers the social desirability, political legitimacy, economical viability, environmental sustainability and technical feasibility aspects of shared water resources.
Subash Prasad Rai, Aaron T. Wolf, Nayan Sharma, Harinarayan Tiwari

Disaster Management

Frontmatter

20. Flood Disaster Management

Over the past several years, the intensity and frequencies of both riverine and urban flooding are showing increasing trends. In many of the Asian countries including India, flooding due to inundation in low lying areas along river channels as well as localized unprecedented precipitation has become a common feature that has gained the status of disasters causing devastations in terms of loss of lives and huge economic losses every year. The number of people affected by riverine and urban floods is more than any other type of natural disasters. The J&K Floods in 2014, Uttarakhand Floods in 2013 and the mega flood of Chennai (Tamil Nadu) in December 2015 highlight the vulnerability status of India.
The prime reasons of flooding being the reduced carrying capacity of river channels, unusual amount and intensity of rainfall in a localized area, climate change over the past decades, poorly managed land use planning, faulty drainage design, construction & management, lack of real time warning etc. Sometimes, sudden release of water from dams along with other localized phenomena also creates flooding. The increasing ramifications of such disasters have afflicted policy planners, scientists, researchers, academicians and others concerned across the world to find out ways and means to deal with the emerging threats of this typical hydro-meteorological phenomena.
The present chapter discuss in details about the fundamental concept of the management of disasters due to floods. The flood vulnerability status in SAARC countries is also discussed along with the existing vulnerabilities of Indian states. In addition the flood management and mitigation strategies are also suggested along with do’s and don’ts.
R. Ranjan
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Die B2B-Firmensuche für Industrie und Wirtschaft: Kostenfrei in Firmenprofilen nach Lieferanten, Herstellern, Dienstleistern und Händlern recherchieren.

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- ANZEIGE -

Systemische Notwendigkeit zur Weiterentwicklung von Hybridnetzen

Die Entwicklung des mitteleuropäischen Energiesystems und insbesondere die Weiterentwicklung der Energieinfrastruktur sind konfrontiert mit einer stetig steigenden Diversität an Herausforderungen, aber auch mit einer zunehmenden Komplexität in den Lösungsoptionen. Vor diesem Hintergrund steht die Weiterentwicklung von Hybridnetzen symbolisch für das ganze sich in einer Umbruchsphase befindliche Energiesystem: denn der Notwendigkeit einer Schaffung und Bildung der Hybridnetze aus systemischer und volkswirtschaftlicher Perspektive steht sozusagen eine Komplexitätsfalle gegenüber, mit der die Branche in der Vergangenheit in dieser Intensität nicht konfrontiert war. Jetzt gratis downloaden!

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