WMOD00432

• Title: Colorado River Augmentation Demonstration Program - Finding of No Significant Impact
• Date: 9/1/1985
• Weather Modification - Doc Type: Report

I. Purpose and Need

Public ~anning and policy decision have recognized that the existing water
yield of the Colorado River basin will not be sufficient to meet the future
needs of the basin's beneficiaries. Shortages have been predicted for soon
after the turn of the century, a 1 ittl e more than two decades from now.

..

Most of the fl ow of the Colorado Ri ver origi nates from seasonal snowpack in
alpine and subalpine watersheds above 9000 feet in elevation, where winter
precipitation amounts are high and evapotranspiration losses low. In the
region, only a small percent of the available water content in the
atmosphere reaches the surface as snow. The remaining moisture stays in
the atmosphere and disperses wi thout. ever changi ng to snow or rai n. Cloud
seeding can sometimes improve the efficiency of the natural precipitation
process and, under favorable conditions, increase seasonal precipitation by
10 to 15 percent.

The Colorado River Augmentation Demonstration Program is a research program
to obtain basic climatological and cloud physics data to improve the
understanding of the potential of cloud seeding as a water resource manage-
ment option in the Upper Colorado River Basin. It would be carried out on
Grand Mesa, which is located in west-central Colorado in part of Mesa,
Delta, and Gunnison Counties.

The Bureau of Reclamation has conducted winter climatological studies on
Grand Mesa since January of 1983 at sites on top of the mesa. The proposal
now is to continue the climatological data collection and to begin studies
of cloud seeding effects, as part of the Bureau's ongoing analysis of the
potential of precipitation augmentation in the Upper Colorado River Basin.
The data would also be available for other scientific studies to governmen-
tal agencies and to universities and the private sector. The level of
seeding proposed is quite limited in extent and duration, for a research
program, and the Bureau would not seed clouds for the primary purpose of
increasing the snowpack.

.

This environmental assessment has been prepared in compliance with the NEPA
(National Environmental Policy Act) of 1969 and Department of the Interior
and Bureau of Reclamation Instructions. The proposed research would be
conducted by the Bureau in accordance with the Colorado River Basin Act of
1968 (Public Law 90-537), the Colorado River Basin Salinity Control Act of
1974 (Public Law 93-320), and the 1981 House Oversight Hearing on Colorado
River Augmentation, which set out the law and policy for management of the
Colorado River system.

1