Irrigation

R. Nolan ClarkUSDA-Agricultural Research ServiceBushland, TX

Top 10 States - Irrigated AcresState USDA USGS

California 8,139,834 10,100,000

Nebraska 5,692,215 7,820,000

Texas 5,237,584 6,490,000

Arkansas 4,043,382 4,510,000

Idaho 3,188,406 3,750,000

Colorado 2,942,230 3,400,000

Kansas 2,650,486 3,310,000

Montana 1,740,873 1,720,000

Florida 1,613,719 2,060,000

Washington 1,554,813 1,570,000

Source of Water

Wells49%

Off-farm40%

Surface11%

Irrigation Water Use (ac-ft)

State USDA USGS

California 25,153,495 34,200,000

Texas 7,473,880 9,680,000

Idaho 6,030,447 19,100,000

Arkansas 5,516,603 8,870,000

Colorado 5,052,612 12,800,000

Nebraska 4,975,330 9,860,000

Arizona 4,117,652 6,060,000

Kansas 3,589,226 4,160,000

Washington 3,364,585 3,400,000

Oregon 3,255,501 6,810,000

Application Rate (ac-ft/ac)State USDA USGS

Arizona 4.7 6.2

California 3.1 3.4

Washington 2.2 2.2

Oregon 2.1 3.1

Idaho 1.9 5.1

Colorado 1.7 3.8

Arkansas 1.4 2.0

Kansas 1.4 1.3

Texas 1.4 1.5

Nebraska 0.9 1.3

The Ogallala Aquifer

Total Irrigated AcresCensus of Agriculture

0

1

2

3

4

5

6

7

Colorado Kansas New Mexico Oklahoma Texas

States

Irri

gat

ed A

cres

(m

illio

n a

c)

1979

1988

1994

1998

Sprinkler

Applications

SurfaceApplications

Efficiencies of Irrigation Methods

Irrigation Method

Typical

Efficiency

Water Application Needed to Add

4 inches To Root Zone

Water Savings Over

Conventional Furrow

(percent) (inches) (percent)

Conventional Furrow

60 6.7

Furrow with Surge Valve

80 5.0 25

Low-Pressure Sprinkler

80 5.0 25

LEPA Sprinkler

90- 95 4.2 37

Drip 95 4.2 37

Method of Distribution

Sprinkler44%

Gravity51%

Sub-irrigation1%Drip

4%

Colorado

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

Sprinkler Gravity flow Drip or trickle Subirrigation

Irrigation Method

Acr

eage

(in

mill

ion

s)

1979198819941998

Texas

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

Sprinkler Gravity flow Drip or trickle Subirrigation

Irrigation Method

Acr

eage

(in

mill

ion

s)

1979

1988

1994

1998

5%

1%

75%

19%

Diesel Gasoline Electric LP or Natural Gas

Colorado, Percent by Acres

75%

10%

15%

Diesel Gasoline Electric LP or Natural Gas

Kansas, Percent of Acres

35%

1%

30%

34%

Diesel Gasoline Electric LP or Natural Gas

Texas, Percent by Acres

Colorado

0

20

40

60

80

100

120

140

160

Diesel Gas Elec Propane Nat Gas

Power Unit Type

Ave

rage

Pu

mp

ing

Acr

es

1979

1988

1994

1998

Texas

0

20

40

60

80

100

120

140

160

Diesel Gas Elec Propane Nat Gas

Power Unit Type

Ave

rage

Pu

mp

ing

Acr

es 1979

1988

1994

1998

0

100

200

300

400

500

600

Required E

nerg

y -

kW

hrs

(m

illions)

0

100

200

300

400

500

600

Win

d E

nerg

y A

vailable

- k

Whrs

/m^2

JanFebMarAprMayJuneJulyAugSepOctNovDec

Irrigation Energy Needed

Wind Energy Available

Irrigation Energy Needed &Wind Energy Available (1997-2000)

0

1

2

3

4

5

6

7 A

vg. Ir

rigation W

ate

r N

eeded -

inches

0

100

200

300

400

500

600

700

Win

d E

nerg

y A

vailable

- k

Whrs

/m^2

JanFebMarAprMayJuneJulyAugSepOctNovDec

Corn Cotton

Wheat Wind Energy

Irrigation Water Needed &Wind Energy Available

Powering Electric Pumps

• Average size 40-50 kW

• Existing electric grid 480V, 3-phase

• Issues:– Market for off-season electric power– Meeting peak demand in summer

Powering Gas/Diesel Pumps

• Average size 120-140 kW

• Existing electric grid 120-240V, single-phase

• Issues:– Weak grid for excess power generated– Stand-by generator to meet peak demand

in summer