WSP00250

• File Number: 8220.700
• Description: Colorado River
• State: CO
• Basin: Colorado Mainstem
• Date: 11/1/1966
• Author: Charles J. Meyers
• Title: The Colorado River
• Water Supply Pro - Doc Type: Report/Study

[Vol. '9: Page I

ity of a subsequent

compact has some
Iter is expressed in
:d in the document.
:lear: when is there
:uired to supply to
problcms of inter-
while the compact
onment scheme, it
re, since no express
Ict'S com pass.
'es others unsolved
Jecome the subject

the 1922 compact.
, preceding section:
,ptive use," (2) the
.tion, and (3) the
are all disputes of
, resolve because of
mderlying lack of

compact, there are
,es no overt effort
egotiators: (4) the
: Lower Basin and
~oundwater tribu-

: likely to sharpen
~ation if the water
hwest Water Plan
in, the ambiguities
tion over water in
Jf the five contro-

e term "beneficial
><:tween the basins

.- ~..

~o'.<I11ber 1966]

THE COLORADO RIVER

'9

in ~tions (a) and (b) of ar~c!e III. T~ere is s~.me e:idence that the two
b;1sins disagree over the definitIOn of this term. Arllcle VI of the Upper
Color2do River Compact (the 1948 agreement of the four Upper Basin
st:Ites) provides that "the quantity of the consumptive use of water, which
i.I apportioned by Article JII hereof, for the Upper Basin [shall be deter-
mined] . . . by the inHow-out/low method in terms of man-made depic-
tions of virgin flow at Lee Ferry (net depletion) . . . ."" On the other
hand, section 4(a) of the Boulder Canyon Project Act, which governs the
di,-ision of main-stream water among the three Lower Basin states, defines
consumptive use as "diversions less returns to the river.t1Tfo
The "net depletion" formula takes account of the fact that the Colorado
River system is, on the whole, a wasting stream-that is, a stream that loses
water as it flows to its mouth. The net depletion formula does not charge
u.crs for water they apply to beneficial use if the water would have been
lost anyway in a state of nature. Two examples suffice to make the point.
Suppose a stream naturally overflows a meadow, and a farmer enters and
converts the meadow to a pasture for his livestock. This beneficial use of
water would not be charged under the "net depletion" formula. The use of
$3lvaged water is also not charged. Suppose an oxbow in the channel is
eliminated by an artificial cut, decreasing losses from evapo-transpiration
:and from percolation to groundwater. This salvaged water may be used
without charge under the net depl:tio~ for~ula. As a general proposition,
apart from the effects of ehannelizallon, mcreased consumptive use de-
creases channel losses downstream because there is less water in the stream
to be lost.
On the other hand, under the formula "diversions less return flows to
the river," ~sers are charged with actual consumption at the sites of use. The
Upper BaSIn naturally advocates the "net depletion" definition of "bene-
ficial consumptive use," while the Lower Basin contends for "diversions
Jess return flows."
T!lis disput<: over t!'e meaning of consumptive use must be resolved not
only m construm,g arllcle III (a) and (b) but also article JII (c) of the com-
pact, because arllcle III (c) defines "surplus" as the excess over the aggre-
gate of the.apportionments in article JII(a) and (b) (which of course are
expressed ill terms of "beneficial consumptive use"). As h~retofore indi-
~te?, the Special ~aster in Arizona II. California construed the compact
IJl dIctum as adoptmg the formula "diversions less return flows.""

W1tJ.~ i;e Clyde, Co~/l;c1s BdUJU1J the Upp~ and Lower Btu;ru 011 the Co/orat/o Rive:r in b.
1960). I.Vl!LOPMENT. FllONTIEU FDa RESEAkCH lJ3. IJ9-3I (Western ResourtcS eo'nfaencc
7J. 63 SUI. 35 ('949).
74- 43 U.S.c. \ 6.,,(.) ('964).
7S. Mtulfft&pC1rt 148.