# Presentation: 806837

## Drought Impacts

**Power Production**
**for**
**Boulder Canyon Project **
**&**
**Parker-Davis Project**

## Impacts To Date

## Slide 3

## Slide 4

## Slide 5

## Future Drought Impacts
Boulder Canyon Project

- Boulder Canyon Project

## How Is Hoover Generation Impacted If Drought Continues?

- Reduced Head as Lake Mead Storage Decreases
- Lake Mead Level Drops 10-15 ft. per year with min. objective release (8.23 MAF) from Powell
- Reduced Water Releases When Shortages are Implemented
- No Physical Restrictions But Turbine Output Decreases With Lower Elevation & Water Releases

## Hoover Key Elevations

## Turbine Operation

- Design Head for Turbine Equates to About 1160 ft. Elevation
- Turbines Probably Able to Operate Below 1050 ft. (Minimum Power Pool) at Greatly Reduced Output
- Increased Cavitation & Maintenance at Lower Elevations.  More Operational Limitations.

## Slide 10

## How Far Can Lake Mead Elevation Drop?

- Shortage Protection Criteria Determine the Elevation(s) at Which Water Deliveries are Reduced
- No Shortage Protection Criteria Adopted by Reclamation - Basin States Discussing Alternatives
- Absolute Floor Probably 1000 ft. (Nevada Intakes)

## Mitigation Measures

- Turbine Replacements
- Stainless Steel Wicket Gates
- Involvement In Shortage Protection Criteria/Basin States Discussions
- Operation of Desalter or Other Bypass Alternatives & Reducing Over-Deliveries to Mexico

## Turbine Replacements

- Increased Capacity (10-15%)
- Small Increase In Efficiency & Energy
- Reduced O&M Costs/Operational Limitations
- Cost Approximately $1.3M per Turbine
- Cost Effectiveness
- Quick Payback at Lower Elevations
- USBR Doing Preliminary Evaluation
- Replacements Done in Increments

## Stainless Steel Wicket Gates

- Increased Capacity (5%)
- Small Increase In Efficiency & Energy
- Reduced O&M Costs
- Cost Approximately $1.0M per Turbine
- Cost Effectiveness
- Quick Payback; Not Dependent Upon Elevation
- USBR Doing Preliminary Evaluation
- Replacements Done in Increments

## Shortage Protection Criteria

- Shortage Protection at Higher Elevations Equates to Higher Capacity & Energy
- Same Amounts of Water is Delivered in Long Run
- Storage Between 1000’ & 1050’ = 3 MAF

## 1100 ft. vs. 1050 ft.

- _1100 ft. vs. 1050 ft._
- Avg Capacity = 1573 MW vs 1409 MW (11.6% Diff)
- Avg Energy = 3392 GWH vs 3174 MW (6.9% Diff)
- Same Total Water Deliveries

## Other Measures

- Reducing Bypass Flows to Mexico (Desalter or Fallowing)
- Additional Storage in Yuma Area Would Reduce Over-Deliveries to Mexico
- Combined Maximum Reduction in Releases Would be 200 KAF or Less

## Future Impacts
Parker-Davis Project

- Parker-Davis Project

## Impacts on Parker-Davis Generation

- No Change in Lake Mohave & Lake Havasu Target Elevations
- Therefore Head is Not Affected at Parker & Davis Dams and Generation Varies Only With Water Releases
- Lake Mead Elevation Below 1125 ft. Results in Normal Water Year Releases
- In Normal Water Years P-D Generates About Current Contract Levels of 1346 GWh (Slightly Less Than FY03)

## Impacts on Parker-Davis Generation(Cont.)

- In Shortage Years Davis Generation Is Reduced Almost Proportionally to Water Reductions
- Parker Generation Should Be Unaffected Since Most or All Reductions are Above Parker
- Davis Generation About 80%, Parker Generation About 20 % of Parker-Davis Generation
- Example: 10% Reduction In Water Deliveries = 8% Reduction In Parker-Davis Generation

## Probable Future
Hoover & Parker-Davis
 Generation

- Hoover & Parker-Davis
-  Generation

## Recent Generation Studies

- Boulder Canyon Project Through 2017
- Average Capacity = 1637 MW
- Average Energy = 3889 MWh
- (No Modifications to Units)

## Recent Generation Studies

- Parker-Davis Generation Through 2028
- Average Energy = Approx. 1380 GWh
- (Reviewing Numbers)

## Mead Filling

- Requires Average or Greater Colorado River Basin Runoff
- Lake Powell Fills First Until Volume Greater Than Lake Mead (Equalization)
- Possible to Completely Refill in Few Years But Requires Very Unusual Runoff (Similar to Early 80’s)

## Probable Future GenerationSummary

- BCP Generation Between 3600 GWh and 4100 GWh Most Years
- P-D Generation Near Current Contract Energy of 1346 GWh Most Years
- Lake Mead Must Fill Above Elevation 1145 ft. for Generation Significantly Above These Values
- Generation Would be Significantly Below These Values Only in Water Shortage Years

## For Additional Information
Contact:  Brian Young
	byoung@wapa.gov
	or 602-352-2594

**Contact:  Brian Young**
**	****byoung@wapa.gov**
**	****or 602-352-2594**