In 1948, the Upper Basin states entered into a compact which
apportioned among themselves the waters of the Colorado River
available to the Upper Basin by the 1922 Colorado River Compact.
In 1948, the Upper Basin states entered into a compact which
apportioned among themselves the waters of the Colorado River
available to the Upper Basin by the 1922 Colorado River Compact.
The 1948 Compact apportioned to Arizona 50,000 acre-feet per year
while the other Upper Basin states received a percentage of the
remaining apportionment as follows:
Colorado . . . . . . . . . . . . . . . . . . . . . 51.75%
Utah . . . . . . . . . . . . . . . . . . . . . . . 23.00%
Wyoming. . . . . . . . . . . . . . . . . . . . . . 14.00%
New Mexico . . . . . . . . . . . . . . . . . . . . 11.25%
Under this formula, if 7.5 million acre-feet were available to
the Upper Basin annually, Colorado's apportionment would provide
for the consumptive use of 3,855,375 acre-feet of water annually.
As of 1985, Colorado only beneficially consumed an average of 2.3 million acre-feet of Colorado River water annually.
The 1948 Compact also provides that consumptive uses under the
1922 La Plata River Compact shall be charged to the
apportionments made to the states under Article III of the 1948
Upper Colorado River Compact.
It also apportions water between
Colorado and Wyoming on the Little Snake River in a manner that
gives preference to pre-Compact water rights.
Further, it
requires that Colorado will not cause the flow of the Yampa River
at the Maybell gaging station to be depleted below an aggregate
of 5 million acre-feet for any period of ten consecutive years
reckoned in a continuing progressive series beginning in 1949.
The Compact also provides that any of the Upper Basin states may exceed the
basic apportionment provided that it does not deprive another
state of its apportionment.
