WSPC05058

• File Number: 8040.950
• Description: Section D General Studies - General Water Studies
• State: CO
• Basin: Statewide
• Date: 7/25/1978
• Author: Unknown
• Title: Draft Publication for Water Study
• Water Supply Pro - Doc Type: Report/Study

001377

Secondly, the amount of water available to Colorado is a function

of interstate compacts and U.S. Supreme Court decisions which apportion

the flow of Colorado rivers between this state and several downstream

states.

Since 1922, Colorado has become a party to nine such inter-

state agreements, and is subject to one Supreme Court decree. These

compacts have removed most uncertainties about the division of water

between Colorado and its neighboring states. However, there are

several unresolved questions about the Colorado River Compact, which

covers all the surface water arising on the western slope.

Given compact limitations on the amount of water Colorado can

use; and present patterns of water consumption, it is clear that the

native supplies of the North Platte, Arkansas, and Rio Grande river

basins are, for all practical purposes, already full~ utilized. Only

about 300,000 acre feet of water per year remain, on the average, for

Colorado to consume in the South Platte, and hydrologic conditions

probably prevent use of more than two thirds of that. On the western

slope, favorable interpretations of the Colorado River Compact, coupled

with estimates of virgin flows dating from 1906, indicate that up to

one million acre feet of water per year, on the average, may remain

for consumption in Colorado. However, an unfavorable interpretation of

the compact, or downward revisions of virgin flow estimates, could

result in a substantial reduction in that figure. In addition, on-

going litigation concerning salinity standards under the Federal

Water pollution Control Act could result in restrictions on future

consumption of water from the Colorado River.

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