The Impact of Farm Size on Irrigation Practices and On-Farm

Irrigation Efficiency in the Elephant Butte Irrigation District

Rhonda Skaggs&

Zohrab SamaniNew Mexico State University

Structure of U.S. Agriculture

• Majority of production on few farms

• Off-farm work

• Retirement or residential/lifestyle farms– 54% of all U.S. farms– 7.8% of value of production

• Urban fringe agriculture

• Irrigated river valleys in the West

Irrigation in the West

• 92% of consumptive water use

• Increased competition for water supplies– Municipal– Industrial– Environmental

• Increased irrigation efficiency?– Technologies or techniques

Elephant Butte Irrigation District

• Irrigated farms increased 70%, 1974-1997• Growth in small farms, urban fringe• Dualistic structure pecan production

• This research…– Relationship between farm size & irrigation

practices, efficiency– Potential responses to incentives & water

marketing– Data for 340 pecan orchards

Pecan Farm Size Distribution (2001)

220

67

24 218

0

50

100

150

200

250

2--5 5--10 10--20 20--50 >50Acres

No

. o

f F

arm

s

2001 Pecan Ac-ft vs Acreage

0

1

2

3

4

5

6

7

8

9

10

0 10 20 30 40 50 60 70 80 90 100Farm Size (Ac)

Ac-

ft

2001 Pecan Hrs/Ac/Irrigation vs. Farm Size

0

2

4

6

8

10

0 10 20 30 40 50 60 70 80 90 100

Acres

Hr/

Ac/

Irri

gat

ion

Pecan Average Hrs/Ac/Irrigation (2001)

1.57

0.97

0.76

0.47

0.30

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

2--5 5--10 10--20 20--50 >50

Acreage (ac)

Hr/

Ac/

Irri

gatio

n

Irrigation Duration…

• Hours / acre / irrigation• Indicator of irrigation efficiency

– Deep percolation losses

• Long durations due to– Highly permeable soils– Low discharge at farm turnout (infrastructure)– Surface roughness, unleveled fields

• Guideline = 0.5 hrs/ac/irrigation

Field Verification• Low flows• Small on-farm turnouts• Long fields, rough surfaces• Inadequate infrastructure• Easements, access, common property

• Irrigation≈ Recreation≈ Tradition≈ Lifestyle≈ Meditation

Findings…

• Overdelivery to small farms

• Underdelivery to large farms

• Delivery losses or on-farm application?

• Small orchard nut production– 161 lbs / acre-foot

• Large orchard nut production– 300 lbs / acre-foot

Next step…

• Not feasible to survey producers• More field measurements & “conversations” with

water users

• Programming models for different farms– “They don’t want to spend any money.”– “I’m retired, what else have I got to do?”– “I like to listen to the water.”

• Objective functions?

EBID Distribution of Crops