Implementing Scientific Irrigation Scheduling

to Improve the On-Farm Water Use Efficiency

Marie-Hélène Bernier M.Sc. Student, Department of Bioresource Engineering

June 9th, 2008

Overview

Water Situation in Ontario

Research Problem & Solution Explored

Irrigation Scheduling

Study Area

Data Collection

Results

Conclusions

20% of the world’s freshwater surface supply is stored in the Great Lakes!

The agricultural sector is highly drought-susceptible & frequently suffers from water shortages

But why is it so?

Only 1% is renewable; theremaining part being left from the last ice age

Southern part of the province Competition & localized conflicts

“Apparent” Water Wealth

Sources: Gabriel & Kreutzwiser (1993) & Dolan et al. (2001)

Farm Cash Revenues for 2001

16.1%

14.4%

11.3%7.3%

2.6%2.9%4.4%

10.5%

10.1%

5.3% 15.1%

Dairy products

Cattle and calves

Hogs

Poultry

Eggs

Tobacco

Corn

Fruit and vegetables

Floric and nursery

Soybeans

Other products

Gross Annual Sales of $6.8 billionFarming is Ontario’s second

largest economic sector

Sources: Marshall Macklin Monaghanm et al. (2003) & Statistics Canada (2006)

The province with largest land area under fruit (25 780 ha ) and vegetables (62 967 ha) production

81.3%

11.1%

5.8% 0.6%

0.5%

0.3%0.3%

0.1%Industrial Thermal Power

Industrial Manifacturing

Municipal

Agriculture

Rural Residential

Aquaculture

Industrial Mining

Golf Courses

Ontario's Total Water Withdrawals

Source: Marshall Macklin Monaghanm et al. (2003)

Manufacturing

Water Supply

Ontario's Total Water Consumption

37.7%

28.3%

20.2%

3.9%

3.4%

3.4%

3.2%Municipal

Industrial Manifacturing

Agriculture

Golf Courses

Industrial Mining

Industrial Thermal Power

Rural Residential

Relatively high rate of consumption (79%) compared to other sectors, agriculture is

the 3rd largest water consumer

Sources: de Loë et al. (2001) & Marshall and Macklin Monaghanm et al. (2003)

Manufacturing

Water Supply

In Southern Ontario, horticultural production faces competition especially during summer

Exacerbating Factors

- Expansion of the agricultural sector

- Increasing urban development & tourism

- Potential climate change impacts

Water conservation strategies for horticultural irrigation High priority

Research ProblemSolutions Explored

Assessing Irrigation Performance

- Current irrigation water consumption patterns

- Crop water needs

- Irrigation Water use efficiency

Improving Current Irrigation Scheduling (IS) Practices

- Soil moisture monitoring

- Limit guesswork

- Realize water savings

“Determining accurately WHEN and HOW MUCH

water to apply to a field.”

“To MAXIMIZE irrigation efficiency”

Subjective

- “By the seat of their pants”

Scientific - Soil moisture monitoring

Irrigation Scheduling

Source: Broner (2005)

When and How Much Water to Apply?

Source: Werner (1993)

Soil Moisture Profile

Management Allowable Depletion

(MAD)

Field Capacity

Permanent Wilting Point

Management Allowable Depletion

Crop grown

Irrigation System

Crop Development Stage

Sources: Sanders (1993) & Werner(1993); Ley et al. (1994); Nyvall (1998); Nyvall (2002); Planner (2003); Hanson et al.(2004); OMAFRA (2004); Bierman (2005); Broner (2005); Nyvall & Tam (2005); AgriMet (2007) & LeBoeuf et al. (2007)

Crop Type MAD (%)

Tomatoes 25

Peppers 25

Strawberries 25

Peaches 50

Southern Ontario High Value Horticultural Production

Dresden

3

Source: Mehdi et al., (2007)

3

4

5

Soil Water Content Soil Water Potential-Volumetric Water Content (%)- -Tension or Suction (cbars)-

Time Domain Reflectometry (TDR) Tensiometry

Electrical Conductivity & Capacitance Devices Electrical Resistance Blocks

Survey

- Current IS practices & perceived water needs

- Individual interviews

- Collected data (e.g.: Irrigated acreage,irrigation system type, …)

Climate Data

- Weather Incorporated Innovated (WIN)

Soil Moisture Monitoring Data

- 8 different devices

Assessing Irrigation performance

Water Budget Method

+ -Effective Precipitation (EP) Crop Water Use (CWU)

Irrigation Water (IW) Deep Percolation (DP)

= $

∆S

Effective Precipitation

EP = (R - 5) 0.75

Crop Water Use (ETc)Penman Monteith Method

ETo = 0.408 Δ(Rn- G)+ 900 u2(es - ea)T+273 .

Δ + (1+0.34 u2)

Where: ETo = Reference evapotranspiration [mm/day]Δ = Slope vapour pressure [kPa/°C]

Rn = Net radiation at the crop surface [MJ/m2/day]G = Soil heat flux density [MJ/m2/day]

= Psychometric constant [kPa/°C]u2 = wind speed at 2 m height [m/s]es = Saturation vapour pressure [kPa]ea = Actual vapour pressure [kPa]

es - ea = Saturation vapour pressure deficit [kPa]T = Mean daily air temperature

Crop Coefficient (Kc)Crop Type Growth Stage Kc

Peaches

April 0.2

May 0.3

June (1-15) 0.4

June (16-30) 0.6

July 1

August 1

September 0.95

Tomatoes

From seeding to 1st flower 0.4

From 1st flower to maximum row fill 0.7

Remainder of crop 1

Peppers

From seeding to 1st flower 0.4

From 1st flower to maximum row fill 0.7

Remainder of crop 1

Strawberries

Initial* 0.4

Mid season* 1.05

Late season* 0.7

Source: Peaches, tomatoes and peppers crop coefficients data are taken fromOMAFRA (2004) while strawberries data are taken from Van der Gulik (2001)

Deep Percolation

Field Capacity = 11.2%

Water Budget Method - Results

Site CropRooting Depth

(mm)FC (%)

MSWS(mm)

MSWD(mm)

AE(%)

IT(mm)

IRR(mm)

IWR (mm)

Dresden Peppers 300 12.58 38 9 84 28 11 165

Simcoe-Outside Strawberries 300 18.09 54 14 84 41 16 384

Simcoe-Tunnels Strawberries 300 18.30 55 14 84 41 16 320

Leamington-Surface Tomatoes 300 13.36 40 10 84 30 12 144

Leamington-Buried Tomatoes 300 11.22 34 8 84 25 10 140

Niagara-on-the-Lake Peaches 600 15.43 93 46 68 46 68 136

Water Budget Method

DatePSWS(mm)

EP(mm)

IRR (mm)

DP (mm)

CWU (mm)

CSWS (mm)

May 30 38 0.0 0 0 1.7 36

May 31 36 0.0 0 0 2.3 34

June 1 34 0.0 0 0 1.9 32June 2 32 0.0 0 0 1.7 30

June 3 30 1.1 0 0 0.6 31June 4 31 0.0 0 0 1.2 30

June 5 30 0.0 0 0 1.0 29June 6 29 0.0 11 0 1.3 38June 7 38 0.0 0 0 2.8 36

June 8 36 6.9 0 0 2.2 40

MSWS = FC x CRD100

MSWD = MSWS x MAD

IT = MSWS-MSWD

IRR = MSWD x 100AE

0

10

20

30

40

50

60

70

80

Equ

ival

en

t W

ate

r D

ep

th (

mm

)Leamington Buried, WCR (0-30 cm)

CSWS

FC

IT

PWP

IWR

Water Savings?

SiteExtra Depth

(mm)

Area

(m2)

Extra Volume

(m3)

Volume Applied

(m3)

Extra Water Spent

(%)

Dresden 10 28 329 283 4 586 6

Simcoe-Outside 98 8 822 865 3 573 24

Simcoe-Tunnels 91 8 701 792 2 665 30

Leamington-Surface 50 12 141 607 1 341 45

Leamington-Buried 6 12 141 73 1 964 4

Niagara-on-the-Lake -75 24 282 -1 821 5 213 -35

They could have saved up to 45%!

But what about peaches?∆S = IWA + EP – CWU – DP

IWA = ∆S – EP + CWU + DP

Conclusions

Ontario has water issues too; threaten horticultural production

Solutions explored

- Assessing Irrigation Performance- Improving Current Irrigation Scheduling Practices

Improve irrigation water use efficiency & water savings

In the end, these solutions have the potential to reduce the vulnerability of the industry to increasing competition and drought frequency

Any Questions?

References

AgriMet. (2007). Managing Water in the West. The Pacific Northwest Cooperative Agricultural Weather Network. US Department of the Interior.

Benninghoff, B. D. (2000). An Evaluation of Ontario's Water Allocation System: The Perspectives of Water Users. M.A Thesis. Department of Geography, University of Guelph, Guelph, ON.

Bierman, P. (2005). Managing Irrigation for High-Value Crops. University of Alaska Fairbanks Cooperative Extension Service. FGV-00649.

Broner, I. (2005). Irrigation Scheduling. Colorado State University – Agriculture. No. 4.708. Retrieved December 3rd, 2007 from http://www.ext.colostate.edu/PUBS/crops/04708.html

de Loë, R..C., Kreutzwiser, R. and Ivey, J. (2001). Agricultural Water Use in Ontario. Canadian Water Resources Journal, 26 (1):17-42

Dolan, A. H., Kreutzweiser, R. and de Loë, R. (2001). Rural water use and conservation in southwestern Ontario, Journal of Soil and Water Conservation, 55 (2): 161-171.

ReferencesGabriel, A. and Kreutzwiser, K. (1993). The Ontario drought hazard: a review of

impacts, 1960-1989, and management implications. Canadian Water Resources Journal, 18: 17-132.

Hanson, B., Schwankl, L. & Fulton, A. (2004). Scheduling Irrigations: When and How Much Water to Apply. Water Management Series publication number 3396. Davis, California, Department of Land, Air and Water Resources, University of California.

LeBoeuf, J., Shortt, R., Tan, C. & Verhallen, A. (2007). Irrigation Scheduling for Tomatoes - An Introduction. Ministry of Agriculture, Food and Rural Affairs (OMAFRA).

Ley, T. W., Stevens, R.G., Topielec, R.R., & Neibling, W.H. (1994). Soil Water Monitoring and Measurement. Pacific Northwest Cooperative Extension bulletins – Washington. Oregon and Idaho. (PNW0475).

Marshall Macklin Monaghan, de Loë, R. and Kreutzweiser, R. (2003). Analysis of Agricultural Water Supply Issues. National Water Supply Expansion Program, Province of Ontario. Final Report presented to Agriculture and Agri-Food Canada (AAFC-PFRA)

ReferencesNyvall, J. (1998). Irrigation Scheduling with Tensiometers. Water Conservation

Factsheet, Ministry of Agriculture and Food of British Columbia. No. 577.100-2.

Nyvall, J. (2002). Soil water storage capacity and available soil moisture. Food andFisheries of British Columbia. Ministry of Agriculture. Agdex 550.

Nyvall, J., & Tam, S. (2005). Irrigation System Assessment Guide. Food andFisheries Resource Management Branch. British Columbia Agriculture Council.British Columbia Ministry of Agriculture.

OMAFRA. (2004). Best Practices Management Series: Irrigation Management.Revised Edition. Agdex#700.

Ontario Ministry of Environment. (2005). Guide to Permit To Take WaterApplication Form, Ontario Ministry of the Environment

Planner, B. (2003). Furrow Irrigation Management Plan. Natural ResourcesConservation Service, United States Department of Agriculture.

Shortt, R., Caldwell, W.J., Ball, J. and Agnew, P. (2006). A Participatory Approach toWater Management. Irrigation Advisory Committees in Southern Ontario.Canadian Water Resources Journal, 31(1): 13-24.

Statistics Canada. (2006). The 2006 Census of Agriculture. Retrieved November 12th, 2007, from http://www40.statcan.ca/l01/cst01/agrc31g.htm.

ReferencesVan der Gulik, T. (2001). Crop Coefficients for Use in Irrigation Scheduling, Ministry

of Agriculture, Food and Fisheries of British Columbia. Agdex 561.

Werner, H. (1993). Checkbook Irrigation Scheduling, Irrigation ManagementManual for South Dakota, Cooperative Extension Service, South Dakota StateUniversity, US Department of Agriculture.