WSPC01494

• File Number: 8064.100
• Description: Ute Tribes
• State: CO
• Basin: San Juan/Dolores
• Water Division: 7
• Date: 12/1/1986
• Author: Boyle Engineering
• Title: Southern Ute and Ute Mountain - Ute Indian Reservations - Agronomy Study - Sections 1-5
• Water Supply Pro - Doc Type: Report/Study

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18f8f7 , h' l' b'l't d btaln
o ers an opportunlty to overcome t lS unre la 1 1 Y an 0 '

maximum crop yield under the given growing environment. Given the

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availability of an adequate water supply, it would appear desirable

to develop potential or existing dry land farming areas to

irrigation. However/ careful economic analyses are required to

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demonstrate the feasibility of such a venture since the cost of

developing irrigation water can more than offset the benefits

derived from increased crop production.

Precipitation occurs during each month of the year in the project

area. The summary of average precipitation at several NOAA weather

stations located in the vicinity of reservation lands is shown in

Table 3.5.

Figure 3.7 shows precipitation isohyets.

Average

amounts of precipitation increase from south to north and west to

east.

Approximately 35 to 50 percent of the average annual rainfall

occurs in the 6 month period encompassing April to September. The

project area is considered semi-arid.

A semi-arid region is

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arbitrarily designated as one with annual precipitation averaging

from 10 to 20 inches.

An additional characteristic of the semi-arid

climate is the wide variability of precipitation and temperature

from year .to year.

Deviations from the average may be as large as the

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average. For example, the annual precipitation at Mesa Verde varied

from less than 13 to more than 30 inches over a 20 year period.

Generally, 20 inches is arbitrarily chosen as the dividing line where

non-irrigated agriculture is possible.

The ",our Corners area on the

Ute Mountain Ute Indian Reservation averages less than 10 inches of

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