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