Irrigation in SaskatchewanIrrigation in Saskatchewan

Project Presentation from 2001

Used as notes 2002

Irrigation DesignIrrigation Design

Three basic designs– Sprinkler applied– Surface applied– Trickle applied

Choice of design dependent on irrigator’s situation.

Sprinkler Applied IrrigationSprinkler Applied Irrigation

Water is sprayed through the air in a mist and falls to the ground like rainfall.

Three configurations:– Multi-sprinkler– Single-sprinkler– Boom-sprinkler

Multi-sprinkler SystemsMulti-sprinkler Systems

one pumping unit supplies one mainline pipe unit and supplies various lateral pipe units which have sprinkler heads.

Various Techniques:– Permanent– Hand moved and Tractor Moved– Self propelled as: center pivot and lateral

moved

Single-sprinkler SystemsSingle-sprinkler Systems

gun- type sprinkler that operates under high enough pressure to irrigate 1-6 acres in circumference.

Application Techniques:– Hand moved– Tractor moved– Self Propelled

Boom Sprinkler SystemsBoom Sprinkler Systems

long lateral pipe with two nozzles evenly spaced to provide better water distribution single-sprinkler.

backpressure spins the lateral pipe.will irrigate an area of 1.0 to 2.5 acres

per setting. same techniques of application as the

single-sprinkler.

Surface Applied IrrigationSurface Applied Irrigation

Intensively level or alter land.Water is applied on the ground at

ground level and flows by gravity over the surface of the field.

Level surface applied irrigation has standing water (< 0.1% grade).

Graded surface applied irrigation has flowing water (0.1%-1.0% grade).

Surface Irrigation TechniquesSurface Irrigation Techniques

Three basic techniques of application for both level and graded:– Furrow– Level Border – Contour Levee

Trickle applied IrrigationTrickle applied Irrigation

A system of pumping filtered water directly onto or below the soil surface.

Water is carried through an extensive pipe network to each plant.

Water is expelled out emitters. Emitter differences are the applicationdifferences in technique.Emitters are prone to clogging.

Leaching Caused by IrrigationLeaching Caused by Irrigation

Irrigation water is over applied– soil erosion– leaching of nutrients– leaching of pesticides

Leaching Caused by IrrigationLeaching Caused by Irrigation

Leaching of Nutrients– nitrogen is very water soluble– over application of water can lead to N

deposited in lower soil levels– can also lead to contamination of

groundwater of N

Leaching Caused by IrrigationLeaching Caused by Irrigation

Leaching of Pesticides– Pesticides Must be

• broken down by soil microorganisms

• taken up by plants

• adsorbed to the soil particles

Leaching Caused by IrrigationLeaching Caused by Irrigation

Management– identify soil texture – irrigation schedule

• track of water losses from evapotranspiration• irrigate when 40 - 70 percent of available soil

water is depleted

Soil Water QualitySoil Water Quality IntroductionIntroduction

Water SourcesWater Sources

Surface WaterSurface WaterGroundwaterGroundwaterEffluentEffluent

– MunicipalMunicipal– AgriculturalAgricultural– IndustrialIndustrial

Water Quality GuidelinesWater Quality Guidelines

Increasing SevereProblems Problems

SalinityEC (mS/cm) < 0.70 0.70 - 3.0 > 3.0*TDS (mg/L) < 490 490 - 2100 > 2100SAR (Permeability Effect on Soil)0-3 > 0.7 0.7 - 0.2 < 0.23-6 >1.2 1.2 - 0.3 < 0.36-12 >1.9 1.9 - 0.5 < 0.512-20 > 2.9 2.9 - 1.3 < 1.320-40 > 5.0 5.9 - 2.9 < 2.9Specific IonsSodium - most annual crops use salinity tables

- trees, woody ornamentals < 3 3.0 - 9.0 > 9Chlorides (mg/L) - most annual crops use salinity tables

- trees, woody < 140 140 - 350 > 350Boron (mg/L) - general guideline < 0.70 0.70 - 2.0 > 2

Degree of Irrigation Problem

No Problem

Salinity and SARSalinity and SAR

0

1

2

3

4

0 10 20 30 40

Sodium Adsorption Ratio

Sal

inity

(dS

/m)

+ Drainage Water

Favourable Conditions

Unfavourable Conditions

Specific Ion TolerancesSpecific Ion Tolerances

BoronBoronChlorideChlorideSodiumSodium

Other ConsiderationsOther Considerations

MetalsMetalsNutrientsNutrientsBiological OrganismsBiological Organisms

RemarksBACTERIASalmonella most common; causes gastroenteritis;usually spread by eating contaminated meat;

no reported diseases from irrigation with secondary effluent, but reported outbreaks

with raw sewage.

Esherichia Coli normally present, causes diarrhea in children and gastroenteritis and urinary

infections in adults; not expected to be a problem in treated wastewater

Mycobacteria tuberculosis, skinulcers and leprosy; baclli must be ingested; resists disinfection

and persists for months; little evidence of infection from land application

VIRUSES generally host-specific and cannot replicate outside most cells; tend to concentrate

in sludge; little evidence to indicate a health hazard in effluent of other irrigation water

HELMINTHSNematodes parasitic intestinal worms; eggs are biologically resistant; reported to survive for up

to 7 years in soil; important in sludge (not effluent)

Cestodes usually associated with ingestion of improperly cooked affected meat; usually

Taenia saginata (beef) associated with sludge and would require direct ingestion; not considered an

T. solium (pork) irrigation problem

PROTOZOA enteropathogen protozoa cysts are resistant to disinfectant and environment stress; associated with sludge; direct ingestion required

Irrigation and Soil QualityIrrigation and Soil Quality

VastIntegratedcomplex

Major factors controlling irrigation’s affect on soil qualityStructure and textureBiotic factorIrrigation constitution

Structure and Texture

Foundation of irrigation’s affect on soilRunoff/ erosion/ nutrient loss/ Soil

removalInfiltration/ Structure

Biotic FactorBiotic Factor

Most important and most affected by water

Microbes are the soil MafiaSaline irrigate waterwater loggingcompaction

NutrientsNutrients

LeachingTransformation

Disease Disease

Suppressed incidenceEncouraged incidenceNo affect

Impurities in irrigate water

Many sortsSaltsEffluent