WMOD00011

• Applicant: Don Griffith North American Weather Consultants, Inc.
• Sponsor Name: City and County of Gunnison
• Project Name: Cloud Seeding Evaluation
• Title: The Development, Conduct and Evaluation of a Cloud Seeding Program for the Gunnison River Basin, Colorado During the 2003-2004 Season
• Prepared For: City and County of Gunnison
• Prepared By: North American Weather Consultants
• Date: 8/1/2004
• County: Gunnison
• Weather Modification - Doc Type: Report

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Tahle 4-4 Sno\\' waler equh"alent target sites (Site oo:s correspond to Fig. 4.5)

Site No. Site Name Sile ID Elev. (ft) Lal(N) Lon(W)
I :\1cClure Pass 07K09 9,500 39"08' 107'17'
2 N'orth Lost Trail 07KOI 9,200 39"04' 107'09'
3 Butte 06L11 10,160 3805..1' 106'57'
4 Park Cone 06L02 9.600 38'49' 106'35'
5 POrph)TY Creek 06L03 10.760 38029' 106'20'
6 Keystone 07L04 9.960 38'52' 107'02'
7 Crested Butte 07LOI 8.920 38'53' 107'00'
8 Lake City 07M08 10,160 37'59' 107'15'
9 C ochetopa Pass 06L06 10.000 38'10' 106'36'

4.2.2 Evaluation Results (Snowpack)

The April I SI average sno\',." water content for the control group was 8.25 inches. When
this observed amount was entered into equation (5). the predicted (most prohable) average snow
water content in the target area was 7.89 inches. for all target sites including McClure Pass. The
actual observed Aprills1 average water content in the target was 8.98 inches. This yielded a ratio
of 1.14. \\;hich is a 14% increase over that predicted by the control stations using equation (5).
This suggests that the average April ISl snow \".ater content from the nine target sites was
increased by 1.09 inches.

When the observed control area average snow water content increase for April I Sl (8.25
inches) was entered into equation (6) (which excludes the ~1cClure Pass site). the predicted
average April I sl snow water content in the target area was 7.74 inches. The actual observed
April ISl average water content for this targer group was 8.76 inches. This )ielded an
observed'predicted ratio of 1.13. which is a 13% increase over the value predicted by the control
stations and equation (6). This would equate to an average increase of 1.02 inches.

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