Contents: Preface About the Book About the Author 1. WATER LOGGING – SOIL SALINITY AND DRAINAGE Soil and Water Related Problems Irrigation, Drainage and Associated Problems Water Logging Brief History and Extent of Water Logging Impacts of Water Logging Soil Salinization Drainage Problems in India Prevention, Management and Reclamation Artificial Drainage Types of Drainage Systems Realization of Drainage Needs Global and Indian Scene Questions (Theory) Questions (Objective) 2. SURFACE DRAINAGE METHODS Definition Surface Drainage Requirement and Crops Factors Affecting Design of Surface Drainage Design of Surface Drainage Systems Drainage Coefficient Empirical Formulae for Collector/Main Drains Design Drainage Components and Field Practices Design of Field Drains Outlet Construction Maintenance of Open Drains Field Assessment of Benefits of Surface Drainage Non-conventional Drainage Systems Questions (Theory) Questions (Objective) 3. DRAINAGE INVESTIGATIONS Introduction Stages in Drainage Investigations Reconnaissance Survey Topographic Survey Soil and Geological Survey Photogrammetric Survey Groundwater Surveys Groundwater Investigations Water Transmission Characteristics Hydraulic Conductivity Laboratory Methods Field Methods Drainable Pore Space Subsurface Drainage Coefficient Collation and Application of Data Questions (Theory) Questions (Objective) 4.DESIGN OF SUBSURFACE DRAINAGE SYSTEMS Introduction Layout Drainage Criteria Drain Depth Spacing of Lateral Drains Design Equations (Steady State) Selection of Steady State Equation Unsteady State Equations Fluctuating Water Table Recommendations on Drain Spacing Interceptor Drainage for Sloping Lands Capacity/Size of Drains Drainage of Paddy Fields Questions (Theory) Questions (Objective) 5.DRAINAGE MATERIALS Introduction Materials for Drain Pipes Testing Flexible Pipes Tests on Fittings Load on Conduits Envelopes Need of an Envelope Parameters to Assess theNeed of an Envelope Entrance Head Loss and Resistance Drain Envelope Design Criteria for Granular Envelope Design and Selection of Synthetic Envelope Tests on Synthetic Envelope Materials Organic Envelopes Questions (Theory) Questions (Objective) 6.CONSTRUCTION AND EVALUATION OF SYSTEMS Introduction Pre-installation activities Construction Methods Manual Construction Mechanical Installation Land Drainage for Peat and Muck Soils Drainage Structures Maintenance of Pipe Drainage Systems Inspection and Quality Control Tender Document Organizational Set-up Monitoring and Evaluation Drain Outflow Method to Evaluate Soil Parameters Crop Cutting Experiments Measurement of Sediment Deposits Water and Salt Balance Questions (Theory) Questions (Objective) 7.SPECIAL DRAINAGE TECHNOLOGIES Introduction Mole Drainage Mole Drainage: Indian Experiences Failures and Remedies Drainage for Seepage Interception On-farm Ponds for Seepage Interception Vertical Drainage Theory of Flow to Drainage Wells Bio-Drainage Suitability of Drainage Methods Integrated Drainage Systems Special Activities to Improve Drainage Effectiveness Questions (Theory) Questions (Objective) 8.SALT AFFECTED SOILS:RECLAMATION AND MANAGEMENT Terminology Salt Affected Soils Formation of Salt Affected Soils Extent and Distribution of Salt Affected Soils Reclamation of Alkali Soils Crops and Alkali Tolerance Determination of Gypsum Requirement (GR) Alkali tolerance and Crop Selection The Package (Alkali Lands) Phyto-remediation of Alkali Lands Reclamation of Saline Lands Cropping in Saline Soils under Reclamation Land Modifications and Planting Management The Package (Saline Lands) Reclamation of Saline-Alkali Soils Questions (Theory) Questions (Objective) 9.RECLAMATION AND MANAGEMENT OF ACID SOILS Introduction Definition, Characterization and Formation of Acid Soils Kinds of Soil Acidity Extent and Distribution Causes of Low Productivity in Acid Soils Management of Acid Soils Liming Industrial wastes as Amendments Engineering and Agronomic Measures Crop Selection: Acid Tolerant Crops Special Cases of Acid Soils Questions (Theory) Questions (Objective) 10.CHARACTERIZATION AND MANAGEMENT OF SALINE WATER Introduction Origin of Salts in Irrigation Water Extent and Distribution of Saline Water Chemical Characteristics to Characterize Water Quality Salinity Hazard: Electrical Conductivity (EC) Sodium/Alkali Hazard Toxicity Hazard Combination of Parameters to Assess Water Quality Infiltration Problems Soil Salinization Water and Salt Balance of the Root Zone Leaching Requirement Leaching Fraction and Soil Salinization Management Strategies for Saline/Alkali Water Chemical Amendments Water Quality Guidelines for Irrigation Disposal of saline Drainage Effluents Management of Toxic Water Management of Waste Water Questions (Theory) Questions (Objective) 11.ECONOMIC ANALYSIS ANDSOCIO-ENVIRONMENTAL ISSUES Costs Investment on Machinery Benefits Economic Analysis Evaluation Indices Calculation of Indices Case Studies of Economic Analysis Comparison of Two Drainage Systems Cost Recovery Documenting Indirect Benefits Environmental Impact Assessment Farmers’ Participation Land Drainage: Current Status and Issues Questions (Theory) Questions (Objective) Annexures I - VI Annexure I: Bill of Quantities for Surface and Subsurface Drainage Systems Construction Annexure II: Ground Water Balance Annexure III: Irrigation Water Salinity Limitsfor Selected Crops Annexure IV: Farmer's Consent /Agreement Annexure V:MOA for Farmer Drainage Societies (FDS) Annexure VI: Handing over the Block to Drainage Society Glossary References Answers to Objective Type Questions Conversion Tables Subject index The current book attempts to fill the gap in one of the major subject of land drainage that will have a major impact on production and productivity of irrigated lands. The book Titled `Drainage Engineering: Principles and Practices` deals with the subject of surface and subsurface drainage to reclaim waterlogged salt affected soils. Based on the course curricula as suggested by Deans´ committee constituted by ICAR, the current publication has been divided into 11 Chapters covering all the facets of land drainage as applied to agriculture. Each chapter covers one of the related issues beginning with general introduction to water logging, soil salinity and land drainage in Chapter 1.Surface drainage methods, an essential intervention in monsoon climatic regions and as supplement to the subsurface drainage are included in Chapter 2. Drainage investigations, a precursor to problem diagnosis and to assemble the drainage design parameters are included in Chapter 3. The drainage design procedures such as assessment of drainage depth, spacing and capacity of drains forms the subject matter of Chapter 4. While drainage materials are discussed in Chapter 5, drainage construction procedures and methodologies to monitor and evaluate completed projects are included in Chapter 6. Some of the new drainage techniques such as mole, interceptor, vertical and bio-drainage have been included in Chapter 7 since these can either be applied singly or in integration with horizontal subsurface drainage. Chapters 8-10 deal withreclamation of salt affected soils,acid soils and management of saline water. Eco-friendly reuse and disposal of saline drainage wateralso form the subject matter of discussion of Chapter 10. Cost calculations, socio-economic and environmental issues associated with drainage projects have been included in final chapter 11. Glossary of terms has been added for quick overview of the terms used in the book. Clearly, each and every aspect of surface and subsurface drainage for agricultural lands has been covered in the book.Besides covering the principles of land drainage, field practices have been included making the book a handy tool for specialized training programmes on land drainage. It is believed that the book will find its place in the shelves of students and teachers, field functionaries and libraries of state agricultural universitiesand civil engineering colleges.