WSP06362

• File Number: 8210.470
• Description: Pacific Southwest Interagency Committee
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 11/1/1971
• Author: PSIAC
• Title: Pacific Southwest Analytical Summary Report on Water and Land Resources based on Framework Studies of Four Regions - November 1971
• Water Supply Pro - Doc Type: Report/Study

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1965 19BO 2000 2020

Figure 8.-Irrigation water requirements (depletion).

Upper Colorado, and measures to improve water
quality.
Land. - To meet the projected needs for the
products of irrigated agriculture will require the
acreages of irrigated land shown in figure 9, represent-
ing the net area for which water is provided. Actually,
more new land (approximately I million acres) will
be brought under irrigation than is indicated in figure
9. This is so because irrigation enterprises displaced
by urban growth and other high priority uses will
move to newly developed land without necessarily
affecting the overall total of irrigated acreage.
The regional framework plans include land
management programs for irrigated lands described in
the Land Management section of this report.
Suitability of land for irrigation has been appraised
in the four regions through the use of irrigation land
classes. These consider iimitations imposed by physi.
cal characteristics of the soil and certain economic
factors that would increase development costs. In

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Irrigation

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PACIFIC SOUTHWES~
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1965 1980 2000 2020
Figure 9.-Area to be irrigated.

addition to suitability, the factor of availability has
been applied to eliminate from consideration those
areas already in a high priority use and not likely to
be released within the planning period.

Irrigation land available in the Pacific Southwest is
shown on figure 10.

Each of the four regions has more land suitable
and available for irrigation than will be needed. The
excess of 41 million acres of suitable land is a major
resource of the United States, available for irrigation
if needed and when water can be supplied.

Costs

The installation costs and the annual operation
and maintenance costs for irrigation in the regions of
the Pacific Southwest are shown on figures 11 and
12, respectively.

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