Irrigation Water Management: Opportunities and

ResultsPresented by:

Paul Stoker, Executive Director

Columbia Basin Ground Water Columbia Basin Ground Water Management AreaManagement Area

Columbia Basin GWMA

Grant County

Lincoln County

Adams County

Franklin County

Irrigated Acreage by Crop in the Columbia Basin

Red – Low Value

Green – High Value Crops

Crop Acres Percent

Alfalfa 263,237 28.4%

Grain** 157,628 17.0%

All Other 109,370 11.8%

Late Potatoes 100,404 10.8%

Orchard* 96,768 10.4%

Peas-Dry 49,418 5.3%

Field Corn 45,951 5.0%

Sweet Corn 30,633 3.3%

14Grass Seed*** 27,275 2.9%

Onions 16,509 1.8%

Vineyard 15,218 1.6%

Early Potatoes 9,159 1.0%

Mint 6,605 0.7%

Total 928,175 100.0%

Irrigation Water Management (IWM) Encourages Irrigators To:

Implement irrigation water management technologies.

Conserve water and energy.

IWM Saves Water & Power Resources

“Old irrigation methods were slow, inefficient, and more often than not, guess work. IWM real-time technology reduces our water and energy costs, and increases our crop quality and yield.” ---Wes Boorman, Boorman

Farms, George, WA.

Example of Evapo-Example of Evapo-Transporation (ET) Based Transporation (ET) Based

Irrigation SchedulingIrrigation Scheduling

1993 Growing Season, Grant County Irrigation Project Evaluation, J.D. Miller, March 1994, Pacific N.W. Laboratory

POTATO (Late Russet)

Acres KwH/Acre Inches/Acre Yield Ton/Acre

Non-Participant 1356 851.80 36.8329.95

Participant 1690 717.75 24.4631.94

Total 134.05 12.37 1.99

IWM Savings 15%

IWM Soil Moisture Graph

Nitrate Movement in SoilNitrate Movement in SoilNative Soil

6 5 4 6 7 4 3 3 4 30

50

100

150

200

1 2 3 4 5 6 7 8 9 10

Native Soil shows consistent low levels of nitrate.

Nitrate Movement in SoilNitrate Movement in SoilContinuous High Leaching

17

59

98

68 73

106130

162

126

89

0

50

100

150

200

1 2 3 4 5 6 7 8 9 10

Excessive irrigation leaches nitrate into the soil profile.

Nitrate Movement in SoilNitrate Movement in Soil

Maximum Management Potential

100

11 16 14 20 23 21 18

0

50

100

150

200

1 2 3 4 5 6 7 8

1 2 3 4 5 6 7 8 9 10

Proper irrigation water management saves water and keeps fertilizer in root zone.

“I believe in the time it takes to do moisture monitoring. IWM has given me a better understanding of my farming practices.”

-- Bob Ransom, Benson & Ransom Farms Pasco, WA

IWM 10-Point Plan CriteriaIWM 10-Point Plan Criteria

1. Measure and document the PCC value for 1. Measure and document the PCC value for each each

irrigation system.irrigation system.

2. Determine amount of water delivered to an 2. Determine amount of water delivered to an area. area.

Know the application rate.Know the application rate.

3. Determine when irrigation water should be 3. Determine when irrigation water should be applied, based on: applied, based on:

crop usage rate, crop usage rate, stage of plant growth, stage of plant growth, cooling, cooling, frost control or frost control or salt leaching.salt leaching.

IWM 10-Point Plan CriteriaIWM 10-Point Plan Criteria

44. Be aware of average time needed for soil to absorb required amount of water.

5. Know application rate, irrigation time, rotation time, or stream size to compensate for changes in such factors as intake rate or the amount of water to be applied.

6. Understand distribution uniformity and application efficiency concepts and their implications on IWM:

Have an in-field uniformity evaluation.

Have an Operations and Maintenance Plan.

IWM 10-Point Plan CriteriaIWM 10-Point Plan Criteria

7. Know how to recognize water (and 7. Know how to recognize water (and nitrogen) movement past the crop nitrogen) movement past the crop rooting zone.rooting zone.

8. Maintain records of irrigation applications.8. Maintain records of irrigation applications.

9. Have a soil moisture monitoring system 9. Have a soil moisture monitoring system in place and in place and maintain records.maintain records.

IWM 10-Point Plan CriteriaIWM 10-Point Plan Criteria

10. Average measured irrigation 10. Average measured irrigation application total application total

(seasonal) should not exceed crop (seasonal) should not exceed crop consumptive use by more than 10% … consumptive use by more than 10% …

as as determined by use of :determined by use of :

Agrimet, Agrimet, PAWS,PAWS, Personal weather station evapo- Personal weather station evapo-

transporation (ET) data, transporation (ET) data, Crop water use coefficient curves.Crop water use coefficient curves.

Why the 10-Point Plan is Why the 10-Point Plan is SuccessfulSuccessful

Contract signed pre-season – payment only upon completion.

Site specific to each field. Program implementation oversight. Credibility with agricultural

community Required documentation forces

grower to actively participate 50% cost share by growers buys

grower involvement.

Why the 10-Point Plan is Why the 10-Point Plan is SuccessfulSuccessful

Why the 10-Point Plan is Why the 10-Point Plan is SuccessfulSuccessful

Reimbursement based on actual cost encourages competition among providers

Simple, realistic and easily understandable by growers and consultants

Covers all important aspects of IWM – not just SIS.

Requires growers to sign-up and commit individually in person.

Monetary incentives can provide significant conservation investment returns.

Variable rate cost-share program specifies savings by crop and location.

Incentive payments are based on potential savings.

IWM saves power and water at the field.

Water not diverted from Lake Roosevelt

for irrigation has high value.

Columbia Basin IWM Benefits

Conservation Benefits Conservation Benefits SpreadsheetSpreadsheet

Spreadsheet calculates the potential water and power savings by using Irrigation Water Management in the Columbia Basin.

Four main variables can be entered to customize the spreadsheet to a given scenario.

Spreadsheet creates a variable cost-share value based on different crops and locations.

Summary on the spreadsheet can demonstrate total conservation benefits available. (See Spreadsheet)