1. WEATHER MODIFICATION An Upper Basin Perspective On Winter Cloud Seeding

2. BACKGROUND Colorado River Basin Growth and Water Demand Population Increase Population Increase Current Level of Development Current Level of Development Drought Drought Uncertain Hydrology Uncertain Hydrology

3. Basin States Growth Projections Population in 1000s Population in 1000s state20052025 state20052025 Arizona52306412 Arizona52306412 California34,44149,285 California34,44149,285 Nevada20702612 Nevada20702612 Total41,74158,009 Total41,74158,009 39% increase – 16 million people 39% increase – 16 million people

4. Basin States Growth Projection state20052025 state20052025 Colorado44685188 Colorado44685188 New Mexico20162612 New Mexico20162612 Utah24773487 Utah24773487 Wyoming559702 Wyoming559702 total952011,989 total952011,989 26% increase – 2 1/2 Million people 26% increase – 2 1/2 Million people

6. Lower Basin Uses Arizona, California and Nevada using nearly 100% of their apportionment Arizona, California and Nevada using nearly 100% of their apportionment Lake Mead Inflow (normal) 9.1MAF Lake Mead Inflow (normal) 9.1MAF Lake Mead Outflow+ Evap 10MAF Lake Mead Outflow+ Evap 10MAF Declining Lake Mead Storage Declining Lake Mead Storage Current Uses May Exceed Inflow Current Uses May Exceed Inflow

7. THE DROUGHT 5 years of extreme drought (2000- 2004) 5 years of extreme drought (2000- 2004) Unregulated inflows 62,59,25,51,49 % Unregulated inflows 62,59,25,51,49 % Powell fell to 33% capacity; 145 ft< full Powell fell to 33% capacity; 145 ft< full 2005 - 105% of ave. Powell + 31 feet 2005 - 105% of ave. Powell + 31 feet 2006 – 73% of ave. 2006 – 73% of ave. Is the drought over??? Is the drought over???

11. UNCERTAINTY OF FUTURE NATURAL FLOW Tree Ring Hydrology Predicts More Significant Droughts Tree Ring Hydrology Predicts More Significant Droughts Climate Change – Warming could reduce the natural flow Climate Change – Warming could reduce the natural flow

12. Basin States Initiative Shortage plan Shortage plan Coordinated reservoir operations Coordinated reservoir operations Efficiency Efficiency Conservation Conservation Augmentation Augmentation –Weather modification

13. THE NEED FOR AUGMENTATION Shortage Plan Shortage Plan Coordinated Reservoir Operations Coordinated Reservoir Operations Efficiency Efficiency Conservation Conservation Augmentation – every alternative Augmentation – every alternative –Weather Modification

14. Upper Colorado River Commission Study Potential Use of Winter Cloud Seeding to Augment the Flow of the Colorado River Potential Use of Winter Cloud Seeding to Augment the Flow of the Colorado River North American Weather Consultants in Sandy Utah North American Weather Consultants in Sandy Utah Don Griffith - Meteorologist Don Griffith - Meteorologist

16. Recent seeding programs

17. Identification of Cloud Seeding Potential Existing Areas – to be enhanced and extended Existing Areas – to be enhanced and extended New Potential Areas To Be Seeded New Potential Areas To Be Seeded

19. Previous Cloud Seeding Studies Namedatewater yield Namedatewater yield –BOR 681.87maf –Stanford Res In 721.15maf –North Am Wea 731.31maf

20. Study Conclusions Range of expected increase in snowpack 5%-15% Range of expected increase in snowpack 5%-15% Increase in flow from existing seeded areas @10% = 575,000 ac-ft/yr Increase in flow from existing seeded areas @10% = 575,000 ac-ft/yr Increase in flow from new seeded areas @ 10% = 650,000 ac-ft/yr Increase in flow from new seeded areas @ 10% = 650,000 ac-ft/yr Total increase @ 10% 1.4 Maf/yr Total increase @ 10% 1.4 Maf/yr

21. STUDY CONCLUSIONS CONT. Estimated cost for new programs – $4.8 million Estimated cost for new programs – $4.8 million Estimated upgrades to existing programs - $2.1 million Estimated upgrades to existing programs - $2.1 million Total cost - $7million Total cost - $7million Cost per acre foot - $5 Cost per acre foot - $5

22. RECOMMENDATIONS Just Do It Just Do It