WMOD00575

• Title: Suitability of the Upper Colorado River Basin for Precipitation Management
• Date: 10/1/1969
• Weather Modification - Doc Type: Report

uniform. However, the major part of the runoff occurs
during the spring and early summer months, which is due
primarily to snowmelt.

The design of a moderate scale pilot program of
operational seeding is in progress, serving as a bridge
between experimental programs and the large-scale opera-
tion of the Colorado River Basin [5,11]. The following
two areas were selected by the Bureau of jZeclamation*
for a pilot program.

(1) The San Juan Mountains including drainage
areas from Lake Fork, Colorado, to the New Mexico
border, and

inch per
unit area

I'
I
I

(2) The Upper Basin of the Colorado River including
drainage from Williams Fork, Colorado, to Troublesome
Creek, Colorado.

These regions are shown in Fig. 6. The suitability
of grouped basins from these regions for weather modifi-
cation is discussed in Chapter V, Section 5.

The next chapter discusses the question of defini-
tion and calculation of suitability criteria. Based on
these criteria, the overall suitability of the Upper
Colorado River Basin is assessed in general and for the
pilot areas in particular in Chapter V, Section 5.

IL
Cv
-
~

Mean
Coefficient of Variation
Spring Runoff
Remaining Season Runoff

I . , "--' '. , ~
<D <D <D <D i:D <D i:D
.I> N UJ .I> ()l (1) (1)
0 0 0 0 0 .j>
Water Year

Fig. 3 Annual and spring runoff at Lees Ferry, Arizona

/"
cv
~
c::::J

Mean
Coefficient of Variation
Winter Precipitation
Remaining Season Precipitation
Standard Deviation

~~061
4 P'
3
2 r
/ ,
I .,,' '

ozoc...."'Tl ~)>s: c....c....):>U)
(")Orr1)>ITll>"U:t> CCCfT1
----l<OZCD :::o:::u-< ~~G1"'U

I~

~ 0.64
P

4

OzOc...."T'l~l>:!1:c....c....l>(J)
~~~~~~~~~~~ta

30

20

10

<1J
Ui

csu 1010758400

- Valleci to Dam

/,,024,80

<1J <1J
N N
o '"

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o

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c3

a;
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a;
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<D
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/,,0 29!l1
--Cvo,28

__~01870
Cvo.30

Fig. 4(a) Annual, winter, and monthly precipitation (in inches) for stations
Vallecito Darn and Cascade. P /P represents the ratio of mean winter
precipitation to mean annual ~recipitation.

* Since the initiation of this study the plans of the Bureau were modified. Currently (45) only one area
is.considered: the San Juan Mountains region.

5