Definition, need and advantages of irrigation and drainage
Disadvantages of over irrigation and waterlogging
Status, need and challenges of irrigation development in Nepal
Crops, their seasons and periods, cropping pattern and intensity
Commanded areas and irrigation intensity
Methods of field irrigation and their suitability
Planning of irrigation and drainage projects
Irrigation Water Requirements and Water Availability (6 hours)
Relation between duty, delta and crop periods
Crop water requirements by Penman's method
Operational water requirements; Losses due to seepage and evaporation
Effective rainfall
Irrigation efficiencies and irrigation water requirements
Soil-moisture-irrigation relation
Depth and frequency of irrigation
Design discharges for canals
Water available at source compared to irrigation requirement
Canal Irrigation System and Design of Canals (10 hours)
Classification of canals
Components of a canal irrigation system
Alignment of canals
Canal standards and balancing canal depth
Canal distribution system and methods of water distribution
Sediment transport in canals and tractive force approach
Design of non-alluvial stable canals
Silt theories and design of alluvial canals by Lacey and Kennedy
Design of lined canals with economic analysis
Diversion Headworks (14 hours)
River stages and suitable location of headworks
Component parts of weir/barrage (Detail drawing)
Bligh's, Lane's and Khosla's seepage theories for foundation
Design of weir and barrage with sloping glacis
Design of under sluice and silt excluder
Design of head regulator
Design considerations of settling basin and silt ejector
River Training Works (4 hours)
River characteristics and need of river training
Classification and methods of river training
Design of guide bund and launching apron
Spurs (Types and design considerations)
Flood control (Structural and non-structural methods)
Canal Regulating Structures (8 hours)
Alignment of the off-taking channels
Function of head and cross regulators, outlets, drops and escapes
Design of regulators and escapes
Types of outlet; Design of pipe outlet (Free and submerged)
Types of drop; Design of vertical drop
Cross-Drainage Structures (6 hours)
Need of cross-drainage works
Types and selection of cross-drainage structures with sketch
Design of siphon aqueduct (Detail drawing, drainage waterway and barrel, canal waterway and transition, RCC aqueduct, protection works)
Waterlogging and Drainage (8 hours)
Causes and effects of waterlogging
Symptoms of waterlogging and their detection
Preventive and remedial measures of waterlogging in irrigated land
Drainage of irrigated field and land reclamation
Surface drainage systems and their design (layout planning, internal drainage of bunded fields, external drainage, design of surface drains, remodeling existing natural drains)
Subsurface drainage systems and their design (layout, flow of groundwater to drains, spacing of tile drains, economic diameter of tile drains)
