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Drainage Methods, Laws and Legislation. Project Presentation from 2001 used for notes 2002. Overview. Methods of Drainage Drainage Effects on Water Quality Laws and Regulations for Drainage. Introduction. Purpose: to remove excess water Benefits: Reduced salinity under irrigation
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Drainage Methods, Laws and Legislation Project Presentation from 2001 used for notes 2002
Overview • Methods of Drainage • Drainage Effects on Water Quality • Laws and Regulations for Drainage
Introduction • Purpose: • to remove excess water • Benefits: • Reduced salinity under irrigation • Reduced soil erosion • Better seed germination and establishment • Better plant growth, health, and yield • Less wear and tear on machinery • Early seeding date and more flexibility
Methods of Drainage • An agricultural system of draining fields commonly consists of: 1) A Field Drainage System 2) A Main Drainage System • move water from field system to outlet 3) An Outlet • terminal point of discharge into open water system
Field Drainage System • Removes excess water from soil: • use of one or more drains • possible use of pump to promote flow • Two main types of systems common 1) Subsurface drainage 2) Surface drainage • Type of system chosen depends on problems present
Subsurface Drainage • Used on soils where excess water easily infiltrates into ground, raising the water table • ie: sandy soils under irrigation soils with high water table • Three main field drains used; 1) Pipe Drains 2) Deep Ditches 3) Well Pumping
Subsurface Drainage1) Pipe Drain Systems • Most common method in temperate agriculture • Used for salinity control for irrigation • System consists of field and collector drains • single-sided entry collector pipes • double-sided entry collector pipes • Singular system • Composite system
Subsurface Drainage1) Pipe Drain Systems • Three common layouts: • 1) Natural system • common when a few larger depressions present • 2) Herringbone system • common when more smaller depressions present • on sloping land where only partial drainage required • 3) Parallel grid system • fairly level and uniform fields with uniformly high water table
Subsurface Drainage1) Pipe Drain Systems • Pipe drain materials: • concrete and clay tile • concrete pipe • corrugated metal pipe • bituminous-fibre pipe • plastic pipe • Option of pipe envelope
Subsurface Drainage2) Deep Ditch System • Ditches can be used to remove excess ground and surface water • Cheaper to install • Deep ditches restrict machinery operations • Loss of up to 10% land with ditches • Higher maintenance required to maintain good grade for discharge
Subsurface Drainage3) Pump Drainage • Not very common, effective under one or more of following conditions: • flat land with high water table • permeable aquifers exists • aquifer deep enough for installation of well • ground water under artesian pressure • ground water high quality for irrigation • cheap power
Surface Drainage • Used on agricultural land with high tendency of water ponding due to slow infiltration rate • fine textured soils • impermeable soil layer close to surface • land unevenness causing collection in depressions
Surface Drainage • Drainage commonly through open ditch systems or mole systems • Four types of open shallow ditch systems: 1) Depression ditch 2) Parallel non-passable ditch 3) Parallel passable ditch 4) Cross-slope ditch
Surface Drainage- Open Ditch Systems 1) Depression ditch system: • fields with limited number of pronounced, elongated depressions • depressions drained individually or connected 2) Parallel non-passable ditch system: • fields that are fairly flat to highly uneven • ditches run parallel in field, spaced to amount of water collected • ditches non-passable with machinery
Surface Drainage- Open Ditch Systems 3) Parallel passable ditch system: • soils with similar characteristics as parallel non-passable ditch system • ditches passable with machinery 4) Cross-slope ditch system: • applicable to gently sloping land • ditches placed perpendicular to slope • land cultivated down slope
Surface Drainage- Mole Systems • Used for soils with impermeable soil layers, allowing shallow drainage of excess water • Mole plough pulled behind tractor creating tunnels • Promotes shallow flow of water
Drainage Effects on Water Quality • Reasons for drainage of cropland • Need for concern • Contamination of water bodies • rivers, creeks, estuaries
Nutrients • Nitrate (NO3-) tied up in water through runoff from surface • Subsurface leaching through soil profile • Tolerable to rate when weeds stimulated to grow
Nutrients • Phosphorus (PO4-2) • Tolerable to 0.05mg/L
Chemicals • Herbicide residue • ends up in water bodies • Pesticides • DDT scare
Aquatic Life • Major concern as microorganisms are very important • Mutations, disease and death of aquatic animals
Rainfall • Intensity and duration of rainfall can wash contaminants down drainage ditch/canal • Excess rainfall • Surface drainage • Subsurface drainage
Salinity • Concern as salt can move from one area to another • High water table years
Drainage Laws and Legislation • Legislation History • Present Day • Drainage Approval Process • Drainage Complaints
Legislation History • “Common Law doctrine” • hindered any drainage schemes that would involve the deposit of excess water into a water course or neighbor’s property • flowing water a common resource, not an article of property • did not work well
North West Territories Irrigation Act - 1894 • Government retained ownership of water • only people who have a title from crown grant before 1894 can have possession today • Crown owns virtually all bodies of water, past and present
Water Rights Act of 1931 • First regulatory water resource statute • Transferred jurisdiction from federal to provincial • after amendments, all drainage projects need license • can now sue for losses incurred
Drainage Control Act of 1980 • Prohibits the construction or continued operation of any drainage systems without a permit • replaced all common law • provided a mechanism for settling disputes • lacked resources for proper enforcement
Water Corporation Act - 1984 • Better known as “Sask. Water” • monitors and grants permits for drainage, irrigation and all other uses • still a lot of unapproved drainage
“No person shall commence the construction, alteration, or operation of any works unless he/she has first obtained the written approval of Sask. Water to do so”
But you can…... • channel clear • consolidate sloughs • install culverts
Drainage Approval Process • Pick up application • return with $ • review for potential conflicts • surveying • advertise intentions • “Approval to Construct Works” • “Approval to Operate Works”
Drainage Complaints • make a “reasonable effort” to resolve conflict • informal complaint • formal complaint with $ • notice of filing • investigation (topographic surveys, hydrology study, final report)
Drainage complaints (cont’d) • formal hearing (if requested) • final decision • ruling passed and compliance is mandatory