Economic Considerations for Conveyance & Supply: The Sacramento Delta. Richard Howitt U C Davis American Society of Farm Managers & Appraisers

Transcription

1 Economic Considerations for Conveyance & Supply: The Sacramento Delta Richard Howitt U C Davis American Society of Farm Managers & Appraisers

2 Comparing Futures for the Sacramento-San Joaquin Delta Supported with funding from Stephen D. Bechtel, Jr. David and Lucile Packard Foundation Engineers: Jay Lund, UC Davis* William Fleenor, UC Davis Economists: Ellen Hanak, PPIC* Richard Howitt, UC Davis Biologists: Peter Moyle, UC Davis William Bennett, UC Davis Geologist: Jeffrey Mount, UC Davis *Lead authors 2

3 Outline Problems of the Delta Evaluating water export alternatives Decision analysis What s best? Conclusions 3

4 Problems of California s Sacramento-San Joaquin Delta 4

5 Problems of California s Sacramento-San Joaquin Delta Physical instability Land subsidence Sea level rise Floods Future earthquakes Ecosystem instability Invasive species Habitat alteration Prohibitive costs for maintaining all islands Worsening water quality for agric. & urban users 5

6 Delta of Tomorrow Will be Different Large bodies of open water and higher sea level Increased salinity, habitat variability Higher water quality costs even if all islands remain intact Based on economic value of land and assets, many islands not worth repairing after flooding (blue) 6

7 One future Delta 7

8 Outline Problems of the Delta Evaluating water export alternatives Decision analysis What s best? Conclusions 8

9 Comparing Water Export Strategies Long-Term (to Mid-Century) Current Strategy: through the Delta Peripheral Canal: around the Delta Dual Conveyance: both through and around the Delta No Exports: use other water sources and use less 9

10 Evaluation Criteria: Co-Equal Goals Delta ecosystem Delta Vision: sustainable environment Our report: viability of native fish populations Expert judgment Water supply Delta Vision: reliable water supply Our report: statewide economic costs Construction & operations, water quality, supply cutbacks Use ranges to capture uncertainty 10

11 Fish Population Viability Estimates Probability of Viable Fish Populations (Current Conditions) Proba bility Delta Smelt Striped Bass Longfin Smelt Sacramento R. Salmon 0.00 In-Delta Intakes No Exports Periphe ral Conveyance Dual Inta kes In-Delta Intakes No Exports Peripheral Conveyance Dual Intakes In-De lta Intakes No Exports Peripheral Conveyance Dual Intake s In-Delta Intakes No Exports Peripheral Conveyanc e Dual Intakes 11

12 Outline Problems of the Delta Evaluating water export alternatives Decision analysis What s Best? Conclusions 12

13 Decision Tree for Economic Cost Fish recover Peripheral canal cost No recovery Peripheral canal cost + Reduced export costs Initial Decision Peripheral Canal Dual Facility End water exports Fish recover No recovery Peripheral canal cost + through-delta cost Peripheral canal cost + through-delta cost Reduced export costs Continue through-delta exports Cost of ending all exports Range of sea level rise Never fails Time to major failure Through-Delta cost + Reduced export costs + Water quality costs End water exports Through-Delta cost + Discounted failure & ending export costs Initial Decision Peripheral Canal Continue through- Delta exports Fish Recovery No recovery Through-Delta cost + Discounted failure & peripheral canal costs Follow-up Decision Chance point Through-Delta Cost + Discounted present & future failure and repair costs, reduced export costs and water quality costs Through-Delta cost + Discounted failure, peripheral canal & reduced export costs 13

14 16 Questions with 32 Answers Question Low High Sea level rise (ft) 1) How much will sea level rise by 2050? Probability of extensive Delta failure (annual failure probability in parentheses) (%) 2) With the minimum sea level rise? 34 (1) 88 (5) 3) With the maximum sea level rise? 57 (2) 95 (7) Population viability in 2050 for delta smelt (Chinook salmon in parentheses) (%) 4) Probability of viable fish pop. with continued through-delta exports? 5 (10) 30 (30) 5) Probability of viable fish populations with no Delta exports? 30 (40) 60 (80) 6) Probability of viable fish populations with a peripheral canal? 10 (20) 40 (50) 7) Probability of viable fish populations with dual conveyance? 10 (20) 40 (50) 8) % exports reduced with continued through-delta pumping? ) % reduction in PC exports if fish continue to decline? Economic and financial costs ($ billion) 10) What is the construction cost of a peripheral canal? ) Additional water quality cost from using Delta water? 0.3/year 1.0/year 12) What is the annualized cost of ending Delta exports? 1.5/year 2.5/year 13) Annualized cost to maintain continued through-delta pumping? 0.15/year 0.4/year 14) Cost to water users of a sudden extensive failure of Delta levees? ) Average cost to repair an extensive Delta levee failure? ) What exponent relates export reduction to economic cost?*

15 Through-Delta Pumping: Low Chance of Restoring Fish, High Costs Likelihood of Fish Viability (%) Delta smelt Through-Delta Exports Economic Cost ($Billions/year) 15

16 Ending Exports: Better for Fish, But Even More Costly Likelihood of Fish Viability (%) Delta smelt Through-Delta Exports No Exports Economic Cost ($Billions/year) 16

17 Peripheral Canal: Mid-range for Fish Viability, Least Costly Delta smelt 100 Likelihood of Fish Viability (%) Peripheral Canal Through-Delta Exports No Exports Economic Cost ($Billions/year) 17

18 Is there a better tradeoff? Delta smelt 100 Likelihood of Fish Viability (%) Peripheral Canal Peripheral Canal? Through- Delta Exports No Exports Economic Cost ($Billions/year) 18

19 Dual Conveyance: Similar to PC for Fish, Probably More Costly Likelihood of Fish Viability (%) Peripheral Canal Delta smelt Dual Conveyance Through- Delta Exports No Exports Economic Cost ($Billions/year) 19

20 Similar Ranking for Chinook Salmon Likelihood of Fish Viability (%) Peripheral Canal Chinook salmon Dual Conveyance Through- Delta Exports No Exports Economic Cost ($Billions/year) 20

21 Outline Problems of the Delta Evaluating water export alternatives Decision analysis What s best? Conclusions 21

22 What s best? Alternatives Delta Smelt Statewide Cost Both Objectives* Through-Delta better than peripheral canal Through-Delta better than dual conveyance Through-Delta better than no exports Peripheral canal better than no exports Peripheral canal better than through-delta Dual conveyance better than no exports Dual conveyance better than through-delta No Exports better than peripheral canal No Exports better than through-delta

23 Outline Problems of the Delta Evaluating water export alternatives Decision analysis What s best? Conclusions 23

24 Conclusions The Delta will inevitably be more saline with more open water, for any water export strategy. Changes harm water users, but are likely better for fish especially if export pumping is removed. Peripheral canal seems best for co-equal fish and water supply. No exports best for fish alone. Move expeditiously from Delta levees to protect water supply. 24

25 Build a Peripheral Canal for Economic, Environmental Goals Export users commit up front to pay for facilities Export water users and upstream diverters should contribute funds/water for ecosystem Use water quality savings from a canal Expand PC diversions with fish conditions Do not arbitrarily limit canal size Better environmental operations Use governance & ownership safeguards Use PC benefits to help fund environment 25

26 Actively Prepare for a Changing Delta Ecosystem Habitat conservation plans should prepare for Climate change Rising sea levels Permanent levee failures New invasive species Ecosystem management should favor diverse habitat and flow for multiple species Experimentation and detailed modeling needed Include flooding at least one island 26

27 Develop a New Framework for Delta Governance and Regulation Build a more centralized, decision-capable system State leadership (governor and legislature) is required; stakeholders cannot negotiate on their own Address regulatory consequences of sea level rise, climate warming, and island failures now 27

28 For More Information Research Brief, main report, technical appendices, and movies available at: Photo credit: Harold E. Malde, courtesy of The Nature Conservancy 28