Opportunities and Threats of Irrigation Development in Kenya's Drylands
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Opportunities and Threats of Irrigation Development in Kenya’s Drylands OPPORTUNITIES AND THREATS OF IRRIGATION DEVELOPMENT IN KENYA’S DRYLANDS Volume VI: Turkana County 201 3 Funded by Implemented by European Union Volume VI: Turkana County Final Report 2013 i Opportunities and Threats of Irrigation Development in Kenya’s Drylands DISCLAIMER The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) or European Union (EU) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO or EU in preference to others of a similar nature that are not mentioned. The views expressed in this information product are those of the author(s) and do not necessarily reflect the views or policies of FAO or EU. Volume VI: Turkana County Final Report 2013 ii Opportunities and Threats of Irrigation Development in Kenya’s Drylands ACKNOWLEDGEMENTS The work done by Ocra Company Ltd. in carrying out the study and compiling this report was possible through the efforts of many people whose dedication ensured the success of the study. Firstly, the study was made possible through the generous funding by the European Union, through the FAO Kenya Office. Secondly, Ocra Company Ltd. extends gratitude to FAO Kenya Office for the consultancy contract to conduct this study. The FAO Kenya Office provided effective management and coordination of the study. This study was primarily based on review and analysis of existing secondary data and information. Many agencies and institutions provided valuable data and information on the study areas that made this work possible. We are indebted to the personnel of the County and Sub-county Irrigation, Agriculture and Livestock Offices in Turkana, Isiolo, Garissa, Wajir, Mandera and Tana River for availing their respective sector and sub- sector data and information. In addition, we thank the respective Water Resources Management Authority (WRMA) offices for providing the hydrological data that was a key input in this study. We are also grateful to the respective county National Environmental Management Authority (NEMA) officers for providing insightful information on environmental and social aspects of irrigation development. The study benefitted immensely from the inputs in form of literature, suggestions, critique and recommendations of the following experts of FAO Kenya Office: Robert Allport and Michael Gitonga, and Abdi Ahmed (formerly of FAO). We also appreciate their commitment and patience in reading through the many draft reports that culminated in the production of this final technical report. In addition, Mike provided substantial editorial input in the report for which we are greatly indebted. Finally but not least, we acknowledge the contribution of Mr. Eric Kimani of FAO for his invaluable input in editing, laying out and formatting the report. Ocra Company Ltd. Technical Team Eng. Bernard M. Maina – Irrigation Engineer and Project Manager Phares K. Ragwa – Irrigation Expert and Team Leader Prof. Raphael G. Wahome – Livestock Expert Dr. Rebecca Karanja – Environmental Expert Humphrey Mwathe - Irrigation Water Users Expert Godfrey M. Ndirangu – Agro-Economist John Kinya – Hydro-Geologist Moses Muriuki – GIS Expert Purity Muthoni – Environmental Assistant Volume VI: Turkana County Final Report 2013 iii Opportunities and Threats of Irrigation Development in Kenya’s Drylands LIST OF ABBREVIATIONS ASALS Arid and Semi-Arid lands DM Dry Matter EC Electrical Conductivity EIA Environmental Impact Assessment ESIA Environmental and Social Impacts Assessment ESMP Environmental and Social Management Plans ESP Exchangeable Sodium Percentage ETO Potential Evapotranspiration EU European Union FAO Food and Agriculture Organization of the United Nations GDP Gross Domestic Product GIS Geographical Information Systems HWSD Harmonized World Soil Database KNBS Kenya National Bureau for Statistics KWS Kenya Wildlife Service MCM Million Cubic Metres MWI Ministry of Water and Irrigation NEMA National Environmental Management Authority NDMA Drought Management Authority NGO Non-Governmental Organization O&M Operation and Maintenance RGS River Gauging Station RWUA River Water Users Association SAR Sodium Adsorption Ratio UNESCO United Nations Educational, Scientific and Cultural Organization USA United States of America USDA United States Department of Agriculture TDS Total Dissolved Solids TLU Tropical Livestock Units TOR Terms of Reference WFP World Food Programme WHO World Health Organization WRMA Water Resources Management Authority Volume VI: Turkana County Final Report 2013 iv Opportunities and Threats of Irrigation Development in Kenya’s Drylands TABLE OF CONTENTS ACKNOWLEDGEMENTS ................................................................................................... iii LIST OF ABBREVIATIONS ................................................................................................ iv LIST OF PLATES .............................................................................................................. viii LIST OF FIGURES ............................................................................................................ viii LIST OF TABLES.............................................................................................................. viii EXECUTIVE SUMMARY ..................................................................................................... ix 1. INTRODUCTION ........................................................................................................ 1 1.1 Objectives of the Study .................................................................................................... 1 1.2 Scope of Works ................................................................................................................. 1 2. DESCRIPTION OF TURKANA COUNTY .................................................................. 2 2.1 Location and Size .............................................................................................................. 2 2.2 Human Population ............................................................................................................. 2 2.3 Climate ................................................................................................................................ 2 2.4 Socio-Economic Activities ................................................................................................ 5 3. LAND RESOURCES .................................................................................................. 6 3.1 Land Tenure and Land Use ............................................................................................. 6 3.2 Topography ........................................................................................................................ 7 3.3 Major Soils and Distribution ............................................................................................. 7 3.4 Land Suitability for Irrigation Based on Slope and Soil Characteristics ................... 9 3.5 Soil Salinity Management and Control ......................................................................... 11 4. WATER RESOURCES ............................................................................................. 12 4.1 Surface Water Resources Availability and Reliability ................................................ 12 4.1.1 Turkwel river .......................................................................................................... 12 4.1.2 Kerio river .............................................................................................................. 14 4.1.3 Surface water quality ........................................................................................... 15 4.1.4 Surface water abstraction technologies ............................................................ 16 4.2 Groundwater Resources ................................................................................................ 16 4.2.1 Groundwater availability ...................................................................................... 16 4.2.2 Groundwater quality ............................................................................................. 16 4.3 Conclusions on Water Resources ................................................................................ 17 4.3.1 Irrigation water availability................................................................................... 17 4.3.2 Water quality ......................................................................................................... 17 4.3.3 Potential abstraction methods ............................................................................ 18 5. IRRIGATION POTENTIAL ....................................................................................... 19 5.1 Area Currently under Irrigation along Kerio and Turkwel Rivers ............................. 19 5.2 Proposed Crops and Cropping Patterns ..................................................................... 19 Volume VI: Turkana County Final Report 2013 v Opportunities and Threats of Irrigation Development