Too Little and Too Much Water and Development in a Himalayan Watershed
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Too Little and Too Much: Water and Development in a Himalayan Watershed Editors Hans Schreier Sandra Brown Jennifer Rae MacDonald Too Little and Too Much Water and Development in a Himalayan Watershed Editors Hans Schreier Sandra Brown Jennifer Rae MacDonald Institute for Resources and Environment University of British Columbia August 2006 Copyright @ 2006 Institute for Resources and Environment (IRES) Publisher: IRES-Press, 2202 Main Mall, Vancouver, B.C. V6T 1Z4, Canada Printed in Canada Allegra Print & Imaging 211 W 2nd Ave. Vancouver, B.C. V5Y 3V5 Canada The views and interpretations in this publication are those of the authors. They are not attributable to IRES or the granting agencies (IDRC or SDC) or ICIMOD. Product named does not imply promotion or legal endorsement. ni Acknowledgements We would like to thank the many people who made a major contribution to the Jhikhu Khola watershed project. These include our Nepali team members and field staff, the farmers, all national and international students and various different organizations that provided valuable input and assistance. A major recognition goes to the International Development Research Centre (IDRC, Ottawa) which in 1989 provided the initiative financial support and continued their support throughout the length of the project. Over the 16 year span we collaborated with the following IDRC project officers: Ken Riley, N. Mateo, M. Beaussart, E. Rached, Joachim Voss, Ronnie Vernooy, John, Graham, and Liz Fabjer. They all made a special effort to help us through good and bad times but a special thank you goes to John Graham who was our true supporter, advisor, and friend over the entire length the project. In 1996 the Swiss Agency for Development and Cooperation (SDC-Bern) became the principal donor as part of the expanded PARDYP project. We would like to thank Peter Maag, Christine Grieder, Carmen Thonnissen, Felix van Sury and Karl Schuler for their support and assistance. Initially the project was housed in the HMG Topographie Survey Branch and 1994 ICIMOD became the home base for the project. While it was not easy being a field-based research project in an institution that focuses primarily on information dissemination, we benefited significantly from being associated with an international institution. We would like to thank for following individuals for their collaboration and assistance. They all made a major contribution to the project and enriched our experience: Richard Allen and his successor Roger White, the PARDYP project coordinators 1996-2006 The leader for the other PARDYP watershed teams J. Xu (China), H. Shah (Pakistan), P.B. Kothiary and S. Bhuchar (India) Our Swiss colleages from the University of Bern particularly: Jurg Merz, Bruno Messerli, Rolf Weingartner and Eve Wymann Brian Carson (Roberts Creek, B.C. previously LRMP) A special thank-you goes to the original Nepali team. Without their enthusiasm and dedication the project would never have succeeded. P.B Shah was our inspirational leader. Without his integrity, dedication, enthusiasm, local knowledge, and organizational capacity this project would have never survived the political, logistical and management difficulties encountered over the years. Gopal Nakarni engineered the production of all iv infrastructure and was the committed organizer of field based activities. Bhuban Shrestha has been incredibly loyal as our database / GIS / multi- media creator and manager, and excelled in all field and office tasks. Pathak was instrumental in helping us in the early stages to get hydrometric and erosion monitoring off the ground. All four were dedicated and delightful people to work with, and they all enriched our lives. Jurg Merz played a pivitol role in keeping the research program alive during the political conflict. Words are insufficient to measure the contribution and enthusiastic support provided by Sandra Brown. The final thank you goes to Jennifer MacDonald for lier valiant effort in editing and producing the book. Vancouver, BC. August 1, 2006 V TABLE OF CONTENTS Acknowledgements ............................................................................................iii List of Figures ......................................................................................................x List of Tables .................................................................................................... xvi List of Plates .................................................................................................... xxi CHAPTER 1: OVERVIEW OF THE PROJECT 1.1 A Historic Perspective .................................................................1 1.2 Introduction and Objectives ....................................................... 3 CHAPTER 2: AN INTEGRATED APPROACH TO WATERSHED MANAGEMENT IN THE HIMALAYAS 2.1 Why a Watershed Approach ....................................................... 7 2.2 Biophysical Setting ..................................................................... 8 2.2.1 Geology and Soils ............................................................................... 8 2.2.2 Climatic Conditions ............................................................................ 9 2.2.3 Land Use ........................................................................................... 11 2.3 The Socio-Economic Characteristics of the Watershed........... 11 2.3.1 People ................................................................................................ 11 2.3.2 Land .................................................................................................. 12 2.3.3 Livelihoods ........................................................................................ 13 2.3.4 Interrelationships: People, Land and Livestock ............................... 16 CHAPTER 3: DYNAMIC CHANGES OVER TIME: 1989-2004 3.1 Population and Socio-economic Trends .................................... 19 3.1.1 Population Dynamics ....................................................................... 19 3.1.2 Economic Well-being ......................................................................... 22 3.1.3 Production System Dynamics .......................................................... 23 3.1.4 Farm Gross Margins ........................................................................ 24 3.1.5 Farm Size and Food Security .......................................................... 27 3.1.6 Subsistence versus Commercial Production .................................... 28 3.1.7 Conclusions ....................................................................................... 29 VÎ 3.2 Land Use Dynamics 1947-2004 ................................................ 31 3.2.1 Changes in Land Use Categories between 1947 and 2004 ............. 31 3.2.2 Changes in Land Use Intensification .............................................. 36 3.3 Soil Nutrient Dynamics ............................................................ 40 3.3.1 Nutrient Status in the Watershed .................................................... 40 3.3.2 Factors that Influence Soil Nutrients .............................................. 42 3.3.3 Soil Nutrient Changes Ouer Time .................................................... 45 3.3.4 Calculating Nutrient Balances for Individual Fields .................... 49 3.3.5 Conclusions ....................................................................................... 53 3.4 Water Demands, Uses and Supplies ........................................ 54 3.4.1 Water Demand .................................................................................. 54 Domestic use .................................................................................. 55 Agricultural use ............................................................................. 56 Livestock ........................................................................................ 59 Overall demand for human activities .......................................... 60 3.4.2 Water Supp ly ..................................................................................... 60 Domestic supply ............................................................................ 61 Agricultural supply ....................................................................... 63 Perceived changes in water supply .............................................. 65 3.4.3 Su m mary ........................................................................................... 66 3.5 Hydrology and Sediment Transport ........................................ 68 3.5.1 Monitoring Network ......................................................................... 68 Data collection ............................................................................... 69 3.5.2 Water Auailability ............................................................................. 70 Precipitation dynamics ................................................................. 70 Evapotranspiration ....................................................................... 73 Flow regime ...................................................................................75 Storage ........................................................................................... 77 3.5.3 Synthesis of Water Accounting ......................................................... 80 3.5.4 Flooding ............................................................................................ 83 Descriptive flood hydrology .........................................................