drainage methods, laws and legislation project presentation from 2001 used for notes 2002
TRANSCRIPT
Drainage Methods, Laws and Legislation
Project Presentation from 2001
used for notes 2002
Overview
1) Methods of Drainage
2) Drainage Effects on Water Quality
3) 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 common1) 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