WMOD00446

• Title: Utah Cloud Seeding Program - Increased Runoff/Cost Analyses
• Date: 2/1/2000
• Weather Modification - Doc Type: Report

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Table 1.
CLOUD SEEDING PROJECT AREA ESTIMATED AVERAGE ANNUAL RUNOFF
1941-1990
Annual Runoff
Project Runoff Areas Project (acre-feet)
Cache County NUP 424,000
West Box Elder NUP 57,800
Tooele County CSUP 43,300
Sevier River CSUP 653,000
Cedar-Beaver CSUP 135,000
West Colorado CSUP 41'1,500
Virgin River CSUP 192,400
Total 1,917,000
Northern Utah Project (NUP) 481,800
Central and Southern Utah Project (CSUP) 1,435,200

Appendix A. The annual runoff for the Northern Utah project areas is 481,800 acre-feet.
The annual runoff for the Central and Southern Utah project areas is 1,435,200 acre-feet.
The total annual runoff for both projects is 1,917,000 acre-feet.

Precipitation Increase from Cloud Seeding

Most of the cloud seeding activity in the Utah project areas occurs during the
December-March period. Target and control analyses, using precipitation gages in the
cloud seeding project areas (target areas) and control precipitation gages in upwind
unseeded areas located in Idaho, Nevada and Arizona, have been made and published
(see References) by North American Weather Consultants. The data and analyses have
been reviewed and confirmed by the Division of Water Resources. In addition, target and

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