WSP00530

• File Number: 8142
• Description: Trinidad Reservoir
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 4/1/1961
• Author: US DoI BoR
• Title: Special Report on Irrigation Function Trinidad Project Colorado
• Water Supply Pro - Doc Type: Report/Study

301;)

.

Monthly distribution of the headgate irrigation requirement
was based on a report compiled by C. W. Thornthwai te Y entitled
"An /lpProach Towards a Rational Classification of Climate". The
mean monthly temperatures at Trinidad C .A.A. Airport Station near

Hoehne, Colorado, based on the total period of record, were converted

from degree Fahrenheit to degree Centigrade and a heat index was

obtained from Mr. Thornthwaite's Table IV, page 92. The monthly

heat index figures were then adjusted by the correction factors,

expressed in units of 30 days of 12 hours each for 370 north lati-

tude, found in Table V, page 93. The adjusted index figures were

then converted to percentages of the annual total. The small per-

oentage distributio~ for February and March were included in the

.

April amount and the small November percentage was included in the

October amount as the average growing season was determined to be

April through October. An average monthly distribution of the

headgate irrigation requirement through the growing season was

estimated as follows:

Month

Headgate irrigation
requirement
(acre-feet per acre)

Percent

April.

0.22
0.34
0.56
0.68
0.62
0.40
0.28

7
11
18
22
20
13
9

May.. .;

.

June .
July.
August
September.
October. . .

.

.

.

Growing season total

3.10

100

.

Y Thornthwaite, C.W. -Jan. 1946, An Approach Towards a
Rational Clas5ification of Climate. (Pages 55 through 94 of the
Geographical Review for Jan. 1946) U.S. Department of Agriculture.

25