WSPC00493

• File Number: 8230.100.10
• Description: Colorado River - Interstate Litigation - Arizona Vs California
• State: AZ
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 6/3/1963
• Title: AZ Vs CA - Determination of Rights of States of the Lower Colorado River Basin to Waters of the Main Stream of the Colorado River - Opinion of the Supreme Court of the US - RE AZ Vs CA
• Water Supply Pro - Doc Type: Report/Study

002188

14

ARIZONA v. CALIFORNIA.

argument would be much more water for California and
much less for Arizona. California also argues that the
Act neither allocates the Colorado River waters nor gives
the Secretary authority to make an allocation. Rather
she takes the position that the judicial doctrine of equi-
table apportionment giving full interstate effect to the
traditional western water law of prior appropriation
should determine the rights of the parties to the water.
Finally, California claims that in any event the Act does
not control in time of shortage. Under such circum-
stances, she says, this Court should divide the waters ac-
cording to the doctrine of equitable apportionment or the
law of prior appropriation, either of which, she argues,
should result in protecting her prior u~es.
Our jurisdiction to entertain this suit is not challenged
and could not well be since Art. III, ~ 2, of the Constitu-
tion gives this Court original juri~iction of actions in
which States are parties. In exercising that jurisdiction,
we are mindful of this Court's often expressed preference
that, where possible, States settle their controversies by
"mutual accommodation and agreement." 32 Those cases
and others '3 make it clear, however, that this Court does
have a serious responsibility to adjudicate cases where
there are actual, existing controversies over how inter-
state streams should be apportioned among States. This
case is the most recent phase of a continuing controversy
over the water of the Colorado Hiver, which the States
despite repeated efforts have been unable to settle.
Resolution of this dispute requires a determination of
what apportionment, if any, is made by the Project Act
and what powers are conferred by the Act upon the Secre-
tary of Interior. Unless many of the issues presented

32 Colorado v. Kamas, 320 U. S. 383, 392 (1943); Nebraska v.
Wyoming, 325U. S. 589, 616 (1945).
33 E, g,; Kansas v, Colorado, 185 U. S. 125 (1902); New Jersey v.
New York, 283 U. S, 336 (1931).