WSP10942

• File Number: 8021
• Description: Section D General Correspondence-Western States Water Council
• Date: 2/19/1966
• Title: Western States Water Council Meeting Attachment No 10-Montanas Water Conservation Measures
• Water Supply Pro - Doc Type: Report/Study

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The 1959 u. S. CenSU3 of Agriculture ,ho"'3 that of Montana's
approximately 2 million acres of irrigated land, 72". is irrigated

by "'ater distributing organizations such as the state ~'ater

Conservation Board, the U. S. Bureau of ~eclamation, the U. S.

Bureau of Indian Affairs, and private irrigation districts and

ditch companies. Organizations such as these do, of cour3e,

exercise some controls over the quantities of ,,'ater used by their

irrigators. In addition, the CenSU3 sho'.'s that the average

annual quantity of ,.'ater delivered to irrigated land in io1o:ntana

by these '.'ater distributing organizations is 3.2 acre-feet Fer

acre and this is slightly less than the average for the eleven

17estern States.

The U. S. Soil Con3ervation Service reports that on farms

and ranches in Montana there are approximately 135 miles of

ditches and cana13 '.'hich have been lined '.'ith either bentonite or

concrete. In addition, there are approximately 280 miles of

irrigation pipelines employed by private users throughout the

State. Although the total irrigated acreage under sprinkler

systems is unkno','n, sprinklers usually conserve considerably more

irrigation water than do gravity systems and Montana has 1,900

sprinkler systems in use at the present time.

'I'he U. S. Bureau of ~eclamation delivers ,,'ater to approxi-

mately 12~ of :~ntana's irrigated land and 73 miles of canals on

Bureau rcrojects have been lined primarily ','i th buried asphalt

membranes. On 17% of the Bureau projects "'ithin N.-ntana, 100%

of the ','ater delivered to the land is measured ~ on 25% of the

projects, 60% of the "'ater is measured ~ on 34% of the project.s,

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