Sediment Problems and Sediment Management in Asian River Basins
Edited by Des E. Walling
IAHS Publ. 349 (2011) ISBN 978-1-907161-24-7, 224 + viii pp. Price £52.00
Sediment problems are assuming increasing importance in many Asian river basins and can represent a key impediment to sustainable development. Such problems include accelerated soil erosion, reservoir sedimentation and the wider impact of sediment on aquatic ecology, river morphology and water resource exploitation. They are further complicated by the impact of climate change and other components of global change in causing both increases and decreases in the sediment load of many rivers in recent years. In order to address these problems, sediment management must be seen as a central component of integrated river basin management. This volume, arising from a workshop organised jointly by the International Commission on Continental Erosion (ICCE) of IAHS, the UNESCO International Sediment Initiative (ISI) and the World Association for Sedimentation and Erosion Research (WASER), focuses on sediment problems in Asian river basins and the many difficulties involved in their effective management. The first section comprises overviews of the sediment problems experienced by individual countries or particular issues relating to the wider region; and the second documents case studies that deal with specific problems and their management. The overviews highlight the sediment problems faced by India and Iran, including soil erosion and reservoir sedimentation; recent changes in the sediment loads of the Hindu Kush-Himalayan rivers and their wider implications; the impact of human activity on the sediment loads of Asian rivers; and new challenges for erosion and sedimentation research in China linked to contemporary issues.
Preface
This Publication is based on the contributions presented at a 2-day workshop on Sediment Problems and Sediment Management in Asian River Basins, which formed part of the Scientific Assembly of the International Association of Hydrological Sciences (IAHS) and the International Association of Hydrogeologists (IAH), held in Hyderabad, India from 7 to 11 September 2009. The workshop was a collaborative venture between the International Commission on Continental Erosion (ICCE) of IAHS, the UNESCO International Sediment Initiative (ISI) and the World Association for Sedimentation and Erosion Research (WASER). The involvement of the UNESCO ISI was particularly important, because UNESCO provided funds to support the attendance of several invited speakers. Additionally the UNESCO ISI has provided funds to support the publication of this Proceedings Volume.
The workshop represented an explicit attempt to strengthen the interaction of ICCE, ISI and WASER with sediment specialists in Asia, and particularly in India and the surrounding countries, and to focus attention on the many important sediment problems faced by the region. The programme of the workshop included the presentations made by the invited speakers and by others who had offered papers to the workshop. The submitted papers provided coverage of a wide range of specific issues and problems. In compiling this collection of papers, the contributions presented at the Workshop have been supplemented by a number of additional contributions by authors who had expressed interest in the Workshop but who were unfortunately unable to attend. These additional papers provide a valuable complement to those presented at the Workshop and usefully expand the coverage of this volume.
The papers included in this publication have been subdivided into two groups. The first group comprises overview papers, which describe the sediment problems experienced by particular countries or focus on particular issues relating to the wider region. The second group comprises papers documenting case studies that deal with particular problems and their management. The overview papers include contributions highlighting the various sediment problems faced by India and Iran, including soil erosion and reservoir sedimentation; recent changes in the sediment loads of the Hindu Kush-Himalayan rivers and their wider implications; the impact of human activity on the sediment loads of Asian rivers; and new challenges for research on erosion and sedimentation in China linked to key contemporary issues.
The case studies provide valuable examples of a range of current sediment problems in Asian river basins and the development of management strategies to address these problems. Two contributions focus on soil erosion. One describes the problems of channel aggradation and reduction in drainage density encountered in many small rivers in Siberia as a result of land clearance and intensification of agricultural activity, and the other addresses the important issue of establishing the magnitude of ‘natural’ or background erosion rates, using an area of the hilly Sichuan Basin in China as an example. Such information is frequently an important requirement when defining management objectives. Problems of developing sediment measurement programmes that are capable of providing reliable information on the response of sediment loads to changing catchment conditions are addressed by two papers. One deals with a small catchment in northern Thailand subject to land-use change and the other describes the establishment of a new monitoring programme for the Upper Ramu River on New Guinea Island, aimed at documenting changes in sediment and related contaminant fluxes associated with the expansion of mining activity within the river basin. The value of using the sediment budget as a tool for characterizing the sediment response of a river basin is usefully demonstrated by a study undertaken in the 3800 km2 Lake Inle catchment in Myanmar and this contribution further demonstrates the wider socio-economic implications of the sediment budget. Taiwan is well known for its high sediment yields and another paper emphasises the sensitivity of this environment to recent climatic change, and particularly the increasing incidence of typhoons. Prediction and modelling of sediment yields are frequently important requirements for developing improved sediment management strategies, because of the need to identify key source areas within a river basin, and two papers report the development and application of such models in the Upper Citarum basin in Indonesia, where landslides are an important driver of sediment mobilisation, and in the catchment of the Sriramsagar Reservoir in India. The impact of human activity on rivers and their sediment loads provided a key theme of the Workshop and case studies of the impact of sand mining in Sri Lanka and the problems of channel degradation along the Yangtze River in China, resulting from the reduction in the sediment load of this river caused by the construction of the Three Gorges Dam, provide additional evidence of the importance of such impacts. .
Reservoir sedimentation represents an important problem in many areas of Asia and four papers provide valuable perspectives on different aspects of this problem. One paper focuses on the potential for using satellite remote sensing imagery to support reservoir sedimentation surveys in India, and another reports on sedimentation in the Akdarya Reservoir in Uzbekistan and its implications for water resource management. The problems of managing reservoir sedimentation in a reservoir constructed on a large river with a high sediment load are well illustrated by a paper describing the development of a sediment management strategy for the Xiaolangdi Reservoir on the Lower Yellow River in China, and the local problems associated with the development of oblique flows in close proximity to many barrrages on Indian rivers are described by a further case study. The deltas and estuaries located at the outlets of river basins frequently face many problems associated with sediment management and their significance is emphasised by a final case study that describes the problems of managing the densely populated Meghna Estuary in Bangladesh, which channels water from the Ganges, the Brahmaputra and the Meghna River into the Bay of Bengal and which is highly sensitive to floodwater and sediment inputs from the contributing river basins as well as potential changes in sea level.
Thanks are extended to all those who helped in the organisation of the workshop, including Manfred Spreafico, Jim Bogen, Chunhong Hu and Anil Mishra, who were co-convenors with myself, and Bhanu Neupane, Ramasamy Jayakumar and Anil Mishra from UNESCO, who worked behind the scenes to secure financial support for several participants and to make their travel and accommodation arrangements. Anil Mishra, from the UNESCO Division of Water Sciences in Paris, is also thanked for his encouragement and support throughout the production of this publication. Finally, very special thanks are due to Penny Perrins and Cate Gardner at IAHS Press in Wallingford for coordinating the production and publication of this volume.
Des E. Walling
Geography, College of Life and Environmental Sciences, University of Exeter
Amory Building, Rennes Drive, Exeter, EX4 4RJ, UK
Contents
1 / Overview Papers
Sediment problems and sediment management in the Indian Sub-Himalayan region Umesh C. Kothyari / 3
An overview of sediment problems and management in Iran
Seyed Hamidreza Sadeghi / 14
The changing sediment loads of the Hindu Kush-Himalayan rivers: an overview X. X. Lu, S. R. Zhang, J. C. Xu & J. Merz / 21
Human impact on the sediment loads of Asian rivers Des E Walling / 37
New challenges in erosion and sedimentation research: a Chinese perspective Zhaoyin Wang, Lijian Qi, Guoan Yu & Cheng Liu / 52
2 / Case Studies
Agricultural activity as cause of aggradation of small Siberian rivers
Valentin Golosov, Nadezda Ivanova & Svetlana Ruleva / 73
Natural erosion rates and sediment delivery ratios in the Hilly Sichuan Basin, southwest China, since the Mid-Pleistocene Hongwei Zhu, Xinbao Zhang, Anbang Wen, Yunqi Zhang, Yangchun Wang, Yongqing Qi & Xiubin He / 80
Sediment load monitoring in the Mae Sa catchment in northern Thailand
Alan D. Ziegler, Lu Xi Xi & Chatchai Tantasarin / 86
River sediment monitoring for baseline and change characterisation: a new management tool for the Ramu River Communities in Papua New Guinea
Nick A. Chappell, Wlodek Tych, Phil Shearman, Barbara Lokes & John Chitoa / 92
Placing sediment budgets in the socio-economic context for management of sedimentation in Lake Inle, Myanmar Takahisa Furuichi & Robert J. Wasson / 103
The changing rainfall–runoff dynamics and sediment response of small mountainous rivers in Taiwan under a warming climate Shuh-Ji Kao,
J. C. Huang, T. Y. Lee, C. C. Liu & D. E. Walling / 114
Spatially-distributed assessment of sediment yield and shallow landslide potential area in the upper Citarum River basin, Indonesia Apip, Kaoru Takara & Yosuke Yamashiki / 130
Sediment yield investigations for controlling sedimentation in the catchment of the Sriramsagar reservoir, India B. Venkateswara Rao, K. Srinivasa Reddy &
P. Ravi Babu / 141
River sand mining and associated environmental problems in Sri Lanka
Ranjana U. K. Piyadasa / 148
Channel degradation in the Yangtze River after the impoundment of the Three Gorges Project Y. T. Li J. Y. Deng / 154
Assessment of reservoir sedimentation using remote sensing Sharad K. Jain & Sanjay K. Jain / 163
Sedimentation of reservoirs in Uzbekistan: a case study of the Akdarya reservoir, Zerafshan River Basin Shavkat Rakhmatullaev, Frédéric Huneau, Masharif Bakiev, Mikael Motelica-Heino & Philippe Le Coustumer / 171
Research on key technology for sediment management in large-scale reservoirs Dongpo Sun, Mingquan Geng & Cheng Liu / 182
Sedimentation behind barrages and oblique river flow Kapileswar Mishra & Dhrubajyoti Sen / 193
Sediment dispersal processes and management in coping with climate change in the Meghna Estuary, Bangladesh Maminul Haque Sarker, Jakia Akter,
Md Ruknul Ferdous & Fahmida Noor / 203
Key word index / 219
Author index / 221
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Sediment Problems and Sediment Management in Asian River Basins
(Proceedings of the Workshop held at Hyderabad, India, September 2009). IAHS Publ. 349, 2011, 3-13.
Sediment problems and sediment management in the Indian Sub-Himalayan region
Umesh C. Kothyari
Dept. of Civil Engineering, Indian Institute of Technology, Roorkee-247667, India
Abstract Alluvial rivers as well as gravel- and boulder-bed rivers in the Indian Sub-Himalayan region pose many problems for the inhabitants of the region. Landslides and floods triggered by heavy rainfall result in colossal damage to life and property. The design, construction and maintenance of dams, reservoirs, bridges and other infrastructure pose important challenges due to the complex role played by the sediment transported by the rivers of the region. This contribution reviews the current status of sediment management in the region by means of illustrative examples and sample data.
Key words sediment; sediment problems; sediment management; Indian sub-Himalayan region
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Sediment Problems and Sediment Management in Asian River Basins
(Proceedings of the Workshop held at Hyderabad, India, September 2009). IAHS Publ. 349, 2011, 14-20.
An overview of sediment problems and management in Iran
Seyed Hamidreza Sadeghi
Department of Watershed Management Engineering, College of Natural Resources and Marine Sciences,
Tarbiat Modares University, Noor 46417-76489, Mazandaran, Iran
Abstract As a developing country, Iran currently faces many sediment-related problems. The high potential sensitivity of much of the country to erosion, inappropriate and unnecessary infrastructure development, land-use change, and unlawful exploitation of resources all contribute to increased soil erosion and sediment mobilisation and associated increased sediment fluxes. However, lack of recognition of the long-term value of soil, the limited numbers of hydrometric stations, the short duration of most records, unreliable and inconsistent data and information, lack of understanding of sediment yield processes and the apathy of both the population in general and experts in the field, serve to mask the severity and intensity of the problem. This contribution attempts to identify and describe the existing sediment problems in the country and presents a number of examples of major changes in sediment fluxes due to natural and human-induced controls. In the present paper an attempt is firstly made to identify and describe the existing problems in the country. Appropriate solutions aimed at combating or minimising the problems and developing effective sediment management strategies are proposed.
Keywords soil erosion; land degradation; sediment management; sediment problems; Iran
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Sediment Problems and Sediment Management in Asian River Basins
(Proceedings of the Workshop held at Hyderabad, India, September 2009). IAHS Publ. 349, 2011, 21-36.
The changing sediment loads of the Hindu Kush-Himalayan rivers: an overview
X. X. LU1, S. R. ZHANG2, J. C. XU3 & J. MERZ4