High Plains States Groundwater Demonstration ProgramParts1&2

• Description: Part I - Overview, Results and Findings; Part II- Cooperative Sponsored Investigation
• State: CO
• Basin: South Platte
• Water Division: 1
• Date: 6/1/2000
• Author: U.S. Department of the Interior Bureau of Reclamation
• Title: High Plains States Groundwater Demonstration Program - Program Summary Report, Parts I & II
• Water Supply Pro - Doc Type: Report/Study

Groundwater Use Trends
Estimates of groundwater use for irrigation are shown in table 4. The three sets of data
columns show the total estimated acre -feet (AF) of fresh surface water and groundwater
used, the percent that is groundwater, and the percent of the total U.S. irrigated acreage
within each State at the 10 -year intervals indicated.
Preparing these estimates over large areas is a major undertaking, and compiling data may
rely on certain assumptions. Individual values can depend on a number of variables and
techniques applied to derive the estimate (USGS, 1977; 1988; 1998). Shifts in water use
can occur with changes in crop patterns, water use efficiency, and conservation measures
applied in response to drought, energy costs, or other factors. Nevertheless, the estimates
are helpful to review the overall magnitude and general trends in water resources.
2.7 U High Plains States Groundwater Demonstration Program
Table 4. Groundwater Use for Irrigation in the Western United States
Estimated
Use 1975*
Estimated Use 1985*
Estimated Use 1995*
* *Total Use
GW
Area
* *Total Use
GW
Area
* *Total Use
GW
Area
(1,000 AF)
% Use
% Total
(1,000 AF)
% Use
% Total
(1,000 AF)
% Use
% Total
Texas
12,600
79.4
15.9
9,100
66.8
11.8
10,600
69.1
10.9
Nebraska
8,200
72.0
10.4
8,140
71.3
13.1
8,460
76.6
12.9
Colorado
10,300
27.2
5.7
13,890
17.2
5.9
14,300
15.8
5.7
Kansas
5,570
93.4
5.6
5,310
94.5
5.2
3,790
93.4
5.3
Wyoming
7,600
3.9
3.1
6,340
5.3
3.2
7,390
2.7
3.4
New Mexico
3,300
45.5
2.0
3,160
41.5
1.7
3,360
42.6
1.7
Oklahoma
1,280
85.9
1.9
499
85.4
0.8
969
88.6
1.0
South Dakota
375
14.7
0.4
516
24.6
0.7
301
31.6
0.5
The High
Plains States
49,225
54.6%
45.0%
46,955
45.7%
42.2%
49,170
45.1%
41.4%
California
38,000
47.4
16.7
34,400
33.7
16.7
32,400
37.3
16.4
Idaho
16,900
23.1
7.0
23,100
16.1
7.2
14,600
19.3
5.2
Montana
12,120
1.0
4.4
9,310
1.0
4.0
9,580
1.0
3.1
Oregon
6,700
14.9
3.9
6,400
8.3
3.6
6,910
14.3
3.2
Washington
6,160
4.2
3.0
5,540
12.7
2.8
7,250
12.7
3.7
Utah
3,840
14.1
3.1
4,020
10.7
1.9
3,960
11.1
2.0
Arizona
7,800
60.3
2.6
6,180
45.3
2.3
6,360
37.6
1.9
Nevada
3,490
16.9
1.6
3,750
22.4
1.5
1,840
39.1
1.0
North Dakota
184
29.3
0.2
173
41.6
0.4
131
50.4
0.3
Other Reclamation
Act States
95,194
30.6%
42.6%
92,873
22.4%
40.4%
83,031
24.7%
36.7%
Total
17 Western States
144,419
38.8%
87.6%
139,828
30.2%
82.6%
132,201
32.3%
78.1%
Total * **
All 50 States
157,000
40.1%
100.0%
153,200
33.4%
100.0%
150,000
36.7%
100.0%
Source: Estimated
Water Use in the United States, (USGS, 1977; 1988; and 1998).
Fresh surface water and groundwater only- does not include reclaimed water, return
flows, etc.
Total estimated irrigated acres in the U.S. were 54 million in 1975, 57.2 million in 1985, and 57.9 million in 1995.
Preparing these estimates over large areas is a major undertaking, and compiling data may
rely on certain assumptions. Individual values can depend on a number of variables and
techniques applied to derive the estimate (USGS, 1977; 1988; 1998). Shifts in water use
can occur with changes in crop patterns, water use efficiency, and conservation measures
applied in response to drought, energy costs, or other factors. Nevertheless, the estimates
are helpful to review the overall magnitude and general trends in water resources.
2.7 U High Plains States Groundwater Demonstration Program