Nile RiverTHE Basin WATER, AGRICULTURE, GOVERNANCE AND LIVELIHOODS EDITED BY Seleshi Bekele Awulachew Vladimir Smakhtin David Molden Don Peden THE NILE RIVER BASIN Water, Agriculture, Governance and Livelihoods The Nile is the world’s longest river and sustains the livelihoods of millions of people across ten countries in Africa. It provides fresh water not only for domestic and industrial use, but also for irrigated agriculture, hydropower dams and the vast fisheries resource of the lakes of Central Africa. This book covers the whole Nile Basin and is based on the results of three major research projects supported by the Challenge Program on Water and Food (CPWF). It provides unique and up-to-date insights on agriculture, water resources, governance, poverty,productiv- ity, upstream–downstream linkages, innovations, future plans and their implications. Specifically,the book elaborates the history,and the major current and future challenges and opportunities, of the Nile River Basin. It analyses the basin characteristics using statistical data and modern tools such as remote sensing and geographic information systems. Population distribution, poverty and vulnerability linked to production systems and water access are assessed at the international basin scale, and the hydrology of the region is also analysed.The book provides in-depth scientific model adaptation results for hydrology, sediments, benefit sharing, and payment for environmental services based on detailed scientific and experimental work of the Blue Nile Basin. Production systems as they relate to crops, livestock, fisheries and wetlands are analysed for the whole Blue and White Nile Basin, including their constraints. Policy, institutional and technological interventions that increase productivity of agriculture and use of water are also assessed.Water demand modelling,scenario analysis and trade-offs that inform future plans and opportunities are included to provide a unique, comprehensive cover- age of the subject. Seleshi Bekele Awulachew was, at the time of writing, Acting Director in Africa for the International Water Management Institute (IWMI),Addis Ababa, Ethiopia. He is now Senior Water Resources and Climate Specialist at the African Climate Policy Center (ACPC), United Nations Economic Commission for Africa (UNECA),Addis Ababa, Ethiopia. Vladimir Smakhtin is Theme Leader – Water Availability and Access at IWMI, Colombo, Sri Lanka. David Molden was, at the time of writing, Deputy Director General – Research at IWMI, Colombo, Sri Lanka. He is now Director General of the International Centre for Integrated Mountain Development (ICIMOD), Kathmandu, Nepal. Don Peden is a Consultant at the International Livestock Research Institute (ILRI), Addis Ababa, Ethiopia. THE NILE RIVER BASIN Water, Agriculture, Governance and Livelihoods Edited by Seleshi Bekele Awulachew, Vladimir Smakhtin, David Molden and Don Peden First edition published 2012 by Routledge 2 Park Square, Milton Park,Abingdon, Oxon OX14 4RN Simultaneously published in the USA and Canada by Routledge 711 Third Avenue, New York,NY 10017 Routledge is an imprint of the Taylor & Francis Group, an informa business © 2012 International Water Management Institute All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. Trademark notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging-in-Publication Data The Nile River basin : water, agriculture, governance and livelihoods / edited by Seleshi Bekele Awulachew ... [et al.]. p. cm. Includes bibliographical references and index. 1.Watershed management–Nile River Watershed. 2.Water resources development–Nile River Watershed. 3.Water-supply–Nile River Watershed–Management. 4. Nile River Watershed–Economic conditions. 5.Agriculture–Nile River Watershed. 6. Nile River Watershed–Environmental conditions. 7. Nile River Watershed–History– 20th century. I.Awulachew, Seleshi Bekele. TC519.N6N56 2012 333.91620962–dc23 2012006183 ISBN: 978-1-84971-283-5 (hbk) ISBN: 978-0-203-12849-7 (ebk) Typeset in Bembo by FiSH Books, Enfield CONTENTS List of figures and tables vii Acknowledgements xiv Abbreviations xv Contributors xviii 1 Introduction 1 Seleshi B.Awulachew,Vladimir Smakhtin, David Molden and Don Peden 2 Nile water and agriculture: past, present and future 5 Karen Conniff, David Molden, Don Peden and Seleshi B.Awulachew 3 The Nile Basin, people, poverty and vulnerability 30 James Kinyangi, Don Peden, Mario Herrero,Aster Tsige,Tom Ouna and An Notenbaert 4 Spatial characterization of the Nile Basin for improved water management 47 Solomon S. Demissie, Seleshi B.Awulachew, David Molden and Aster D.Yilma 5 Availability of water for agriculture in the Nile Basin 61 Robyn Johnston 6 Hydrological processes in the Blue Nile 84 Zachary M. Easton, Seleshi B.Awulachew,Tammo S. Steenhuis, Saliha Alemayehu Habte, Birhanu Zemadim,Yilma Seleshi and Kamaleddin E. Basha 7 The Nile Basin sediment loss and degradation, with emphasis on the Blue Nile 112 Tammo S. Steenhuis, Zachary M. Easton, Seleshi B.Awulachew,Abdalla A.Ahmed, Kamaleddin E. Bashar, Enyew Adgo,Yihenew G. Selassie and Seifu A.Tilahun v Contents 8 Nile Basin farming systems and productivity 133 Poolad Karimi, David Molden,An Notenbaert and Don Peden 9 Livestock and water in the Nile River Basin 154 Don Peden,Tilahun Amede,Amare Haileslassie, Hamid Faki, Denis Mpairwe, Paulo van Breugel and Mario Herrero 10 Overview of groundwater in the Nile River Basin 186 Charlotte MacAlister, Paul Pavelic, Callist Tindimugaya,Tenalem Ayenew, Mohamed Elhassan Ibrahim and Mohamed Abdel Meguid 11 Wetlands of the Nile Basin: distribution, functions and contribution to livelihoods 212 Lisa-Maria Rebelo and Matthew P.McCartney 12 Nile water governance 229 Ana Elisa Cascão 13 Institutions and policy in the Blue Nile Basin: understanding challenges and opportunities for improved land and water management 253 Amare Haileslassie, Fitsum Hagos, Seleshi B.Awulachew, Don Peden, Abdalla A.Ahmed, Solomon Gebreselassie,Tesfaye Tafesse, Everisto Mapedza and Aditi Mukherji 14 Simulating current and future water resources development in the Blue Nile river basin 269 Matthew P.McCartney,Tadesse Alemayehu, Zachary M. Easton and Seleshi B.Awulachew 15 Water management intervention analysis in the Nile Basin 292 Seleshi B.Awulachew, Solomon S. Demissie, Fitsum Hagos,Teklu Erkossa and Don Peden Index 312 vi LIST OF FIGURES AND TABLES Figures 2.1 The Nile River Basin 6 2.2 Placement of early dams on the Nile 19 3.1 Population growth in the Nile Basin 32 3.2 Water resources in the basin 33 3.3 Poverty levels in the Nile Basin 38 3.4 Biophysical vulnerability 42 3.5 Social vulnerability 43 3.6 Water-related risks 44 4.1 Topographic patterns of the Nile Basin 50 4.2 Climatic patterns of the Nile Basin from the Koppen-Geiger climate classification and humidity zones derived from the International Water Management Institute climate atlas 51 4.3 Water sources and sinks in the Nile Basin 52 4.4 Soil properties in the Nile Basin 53 4.5 Vegetation profiles in the Nile Basin 53 4.6 Environmentally sensitive areas 54 4.7 The dominant principal components of the biophysical factors 56 4.8 Water management classification framework for the Nile Basin 57 4.9 The hydronomic zones of the Nile Basin 58 5.1 The Nile Basin, showing major tributaries and sub-basins 63 5.2 Mean annual precipitation, mean annual potential evapotranspiration and humidity index for the Nile Basin 64 5.3 Schematic of Nile flows 66 5.4 Spatial patterns of seasonal flow in the Nile sub-basins, displayed as proportion of annual flow in each calendar month 67 5.5 Monthly variation in humidity index for Nile sub-basins 1951–2000, illustrating spatial variability of timing and duration of growing season 68 5.6 Land cover in the Nile Basin 69 vii List of figures and tables 5.7 Water account for the Nile, showing partitioning of rainfall into ET (by land use category) and locally generated run-off for each sub-catchment and the basin as a whole 72 6.1 Biweekly summed rainfall/discharge relationships for Andit Tid,Anjeni and Maybar 89 6.2 Probability of soil infiltration rate being exceeded by a five-minute rainfall intensity for the Andit Tid and Anjeni watersheds 90 6.3 Average daily water level for three land uses calculated above the impermeable layer superimposed with daily rainfall and for three slope classes in the Maybar catchment 93 6.4 Piezometric water-level data transect 1 in the upper part of the watershed where slope is even 94 6.5 Plot run-off coefficient computed from daily 1988, 1989, 1992 and 1994 rainfall and run-off data for different slopes in the Maybar catchment and run-off depths for various slope classes in the Andit Tid catchment 95 6.6 Calibration results of average monthly observed and predicted flow at the Gumera gauge using SWAT 99 6.7 Framework of the coupled Water Balance Simulation Model–Ethiopia and Self- Organizing Map models 100 6.8 Digital Elevation Model, reaches, sub-basins and sub-basin outlets initialized in the Blue Nile Basin SWAT model 101 6.9 Land use/land