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Water Resources Development Teachers Mannual WATER RESOURCES DEVELOPMENT for Engineering Degree Programme as Core Courses for all Disciplines For Department of Technical Education Govt. of Uttarakhand ALTERNATE HYDRO ENERGY CENTRE INDIAN INSTITUTE OF TECHNOLOGY, ROORKEE July 2007 CONTENTS Item Page No. 1. OCCURRENCE OF WATER ON EARTH AND ITS MOVEMENT 1 2. SURFACE WATER- DIVERSION WORKS 5 3. SURFACE AND SUBSURFACE CONSIDERATIONS IN DESIGN 26 OF HYDRAULIC STRUTURES 4. RIVER TRAINING WORKS 34 5. SEDIMENT CONTROL IN CANALS 39 6. OTHER CANAL WORKS 49 7. SURFACE WATER-STORAGE SCHEMS 56 8. GRAVITY DAMS 61 9. EMBANKMENT DAMS 66 10. SPILLWAYS 77 11. SOME SPECIAL PROBLEMS OF HILLY STREAMS 89 12. GROUND WATER 92 13. DECISION SUPPORT SYSTEMS IN WATER RESOURCES 99 LIST OF FIGURES ITEM Page No. 1. OCCURANCE AND MOVEMENT OF WATER 1.1 Hydrologic cycle 1 1.2 Water availability 3 2. SURFACE WATER- DIVERSION SCHEMES 2.1 Typical layout of a canal head works 19 2.2 Typical sections of weir and barrage 19 2.3 Fish ladder 19 2.4 Canal head regulator 20 2.5 Main canal, branch distributary etc. for an irrigation project 21 2.6 Forces on particle- in bed, on sides 20 2.7 Rounding at corner- lined channels 20 2.8 Canal mounting watershed – need of cross drainage works 22 2.9 Typical canal cross sections – in cutting, filling etc. 23 2.10 Power channel – difference in slopes of river and canal 22 2.11 Typical layout of hydropower scheme 24 2.12 Trench weir and settling chamber 25 3. SURFACE AND SUBSURFACE FLOW CONSIDERATIONS 3.1 Hydrostatic pressure distribution 31 3.2 Hydraulic jump 31 3.3 Forced hydraulic jump 31 3.4 Bed scour 31 3.5 Uplift on floor 32 3.6 Exit gradient – force on cylinder 32 3.7 Bligh’s theory 32 3.8 Khosla theory – standard profiles 33 3.9 Khosla theory – actual profile 33 4. RIVER TRAINING WORKS 4.1 Guide banks 36 4.2 Afflux bunds 37 4.3 Spurs 37 4.4 Hockey and T spurs 38 5. SEDIMENT CONTROL IN CANALS 5.1 Shear on bed 45 5.2 Shields’ curve 46 5.3 Velocity and sediment distribution 47 5.4 Helicoidal flow in bends 48 ITEM Page No. 5.5 Sediment excluder 47 5.6 Curved vanes 48 5.7 Skimming platform 48 5.8 Sediment ejector 45 5.9 Settling basin 45 6. OTHER CANAL WORKS 6.1 Ground and canal slope- need for falls 53 6.2 Vertical impact fall 53 6.3 Glacis fall 53 6.4 Aqueduct 54 6.5 Siphon aqueduct 55 6.6 Level crossing 55 7. SURFACE WATER – STORAGE SCHEMES 7.1 Mass curve & storage capacity determination 60 8. GRAVITY DAMS 8.1 Typical section and forces 65 8.2 Elementary profile 65 9. EMBANKMENT DAMS 9.1 Typical sections – homogeneous 74 9.2 Typical sections – zoned 74 9.3 Slip circle 75 9.4 Base parabola 75 9.5 Modification of base parabola 75 9.6 Phreatic line in rock toe 75 9.7 Cutoff – partial and complete 76 9.8 Horizontal blanket 76 10. SPILLWAYS 10.1 Flood routing 84 10.2 Ogee spillway 85 10.3 Chute spillway 85 10.4 Side channel spillway 86 10.5 Shaft spillway 86 10.6 Siphon spillway 87 10.7 Jump basin- appurtenances 87 10.8 Ski jump bucket 87 10.9 Roller bucket- solid and slotted 87 10.10 Gates- vertical, tainter and drum 88 ITEM Page No. 11. SOME SPECIAL PROBLEMS OF HILLY STREAMS 11.1 Types of flow 91 12. GROUND WATER 12.1 Saturated and unsaturated zones 97 12.2 Unconfined and confined aquifers 98 12.3 Cone of depression 98 13. DSS IN WATER RESOURCES 13.1 Typical decision support system 100 13.2 Schematic of a typical knowledge – based expert system 102 13.3 A typical multiplayer ANN 102 13.4 Schematic of learning agents (after russell and norvig) 103 PREFACE Lecture notes for the proposed Engineering Degree Level Course entitled ‘Water Resources Development’ for branches in Electrical, Mechanical, Instrumentation and Electronic Engineering is in accordance with the approved syllabus. These have been prepared by Prof PK Pande, Former Provice Chancellor, Head and Professor of Hydraulics Deptt. of Civil Engg., University of Roorkee (1960-2000) who has been enclosed in various water resources projects in the country. Modern trends in design are brought out. Copies of some relevant published/ unplublished papers on various aspects of design are included. It may be noted that published design papers are relevant to the design practice at the time of publication/ design and must be used/ modified with relevant to current practice at the time of publication/ design and must be used/ modified with relevant to current practice as per reference given in the text. The material in these notes is also part of a book entitled ‘Hydro-electric Engineering Practice in India’ being complied by author. (ARUN KUMAR) Head, AHEC, IIT, Roorkee FOR ENGINEERING DIPLOMA LEVEL COURSE For the branches in Civil, Electrical, Mechanical, Industrial, Agriculture, Environmental, Production, Electric Engg. 1. Course Title: Water Resources Development 2.* Contact Hours: L:48 T:0 P:0 3.* Examination Duration (Hrs.): Theory : Practical : 4.* Relative Weightage : CWS PRS MTE ETE PRE 5.* Credit: 6.* Semester: Autumn Spring Both 7. Pre-requisite: NIL 8. Details of Course: Sl. Contact No. Particulars Hours 1. Government Hydropower policies, environmental issues, SWOT- 3 (Strength weakness opportunity threatening) of hydropower projects, type of clearance required for Hydropower project, master plan, topography, catchments area, types of streams, allotment of site-(Open bid, Mou, Joint venture). 2. Survey & investigation, PFR-(Pre-feasibility report), DPR (Detailed 4 Project Report), Process of development of site (announcement, allotment, clearance, agreement, commissioning).Types of survey- Topographical, metrological, hydrological, ecological, geological. Arial Rainfall Measurement, Type of flow measurement Devices- (Notch, weir, flume), dilution method, and Flow duration curve (important), flood – discharge estimation kripitech formula, dickens formula, English formula, hydrograph, unit hydrograph. 3. Financial institution, SOI Map, Cost / Estimation – wheeling charges, 2 Banking, Moratorium, PPA-(Power purchase agreement), SERC- (State electricity regulatory commission) Hydrological cycle. 4. WATER RESOURCES PLANNING—Water Resources in India, 2 Purpose & Classification of Water Resources Development Projects, Functional Requirements of Multipurpose Projects, Strategies for the Future. 5. HYDROLOGY—Hydrologic Cycle, Precipitation, Runoff, 3 Hydrograph Analysis. 6. PRECIPITATION & PRECIPITATION LOSSES—Forms & Types 3 of Precipitation, Rainfall in India, Measurement of Rainfall, Design Storm, Evaporation & its Estimation, Reducing Reservoir Evaporation, Evapotranspiration, Interception, Storage in Depression, Infiltration, Watershed Leakage. * These are to be decided by the respective University/Board Sl. Contact No. Particulars Hours 7. GROUND WATER—Subsurface Zoning, Water Bearing Material, 5 Aquifers, Steady, unsteady & Ground Water flow. Well Hydraulics, Well Losses, Stream & Seawater Intrusion, Groundwater Investigation. 8. STREAM FLOW—Terminology, Factors Influencing Runoff, Runoff 4 Computation, Runoff Simulation Models, Storage, Discharge Measurements. 9. HYDROGRAPHS—Concepts & Components, Unit Hydrograph, S- 3 Hydrograph, Distribution Graph. 10. DESIGN FLOODS—Introduction, Design Floods, Flood Estimations, 3 Analysis of Regional Flood Frequency. 11. RESERVOIR PLANNING & DAM PLANNING—Investigation, Site 6 Selection, Zones of Storage, Storage Capacity, Sedimentation & Control, Single & Multipurpose Reservoir, Flood Routing. Classification of DAMS, Factors Influencing selection of Dam, Site Selection. 12. SPILLWAYS & DIVERSION HEADWORKS—General, Types, 4 Energy Dissipation, Indian Standards Criteria, Gates, Outlet works. Diversion Headwork Components, Weirs, Khoslas Theory, Silt Control, Site Selection, Effect of Weir on Regime of River. 13. WATER POWER ENGINEERING—General, Classifications, 4 Principle Components, Site Selection of Hydro-Power Plants, Turbines Power House, Water Power Potential Assessment, Design of Hydel Channel. 14. REMOTE SENSING APPLICATION on WATER RESOURCES - 2 Preliminary Concepts Suggested Readings: 1. Arakeri, H.R., Donahue, Roy, “Principles of Soil Conservation & Water Management”. 2. Bower, H., “Ground Water Hydrology”. 3. Central Water Commission, India, “Water Sources of India”, Publication No.30/88,CWC, New Delhi, 1988. 4. Indian Institute of Remote Sensing, Publications on Water Resources. 5. Karanth, K.R., “Ground Water Assessment Development & Management”. 6. Patra, K.C., “Hydrology &Water Resources Engineering”. 7. Sharma, R.K., “A Text Book of Hydrology & Water Resources”. 1. OCCURANCE OF WATER ON EARTH AND ITS MOVEMENT Water is an essential ingredient for sustenance of life. The total quantity of water available on earth is estimated to be about 1400 million cubic kilometer, which is enough to cover the earth with a layer 3 km deep. However, 97.3% of this is saltwater in oceans, thereby leaving only 2.7% freshwater. Again, about 75% of the freshwater lies frozen in the Polar Regions and about 22.6% is groundwater- some of it very deep to be economically extractable. The surface freshwater is thus only about 0.07% of the total water occurring on earth. With increasing population, while the demand for water increases, anthropogenic pressures are rendering many water sources unfit for use because of the high level of pollution. Development and management of water resources is thus one of the important aspects of development at the present time. HYDROLOGIC CYCLE The conceptual model describing the movement and storage of water on earth is known as the Hydrologic Cycle. The energy of the sun is responsible for this cycle (Fig.1.1). There are six processes taking place in the Hydrologic Cycle viz.: 1. Evaporation and Transpiration (Evapotranspiration) 2. Condensation 3. Advection 4. Precipitation 5. Surface Runoff 6. Infiltration and Percolation 1 Water is evaporated from the oceans, inland water bodies and land surface because of the energy supplied by sun. Water vapour also enters the atmosphere due to transpiration by plants and animals. Condensation of this vapour on the nuclei present in atmosphere results in the formation of clouds. The clouds are transported by winds (Advection) and under appropriate conditions result in precipitation in the form of rain, sleet, hail or snow.
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