Using RiverWare to Support the Ongoing Bi-National Discussions for Management of the Colorado River

Transcription

1 Kevin Wheeler P.E. Using RiverWare to Support the Ongoing Bi-National Discussions for Management of the Colorado River Russ Callejo

2 Purpose of Discussions Joint Cooperative Measures for Colorado River Management Mutual Benefits for United States and Mexico

3 Background 1944 Treaty Allotment of Water to Mexico Minute 317 June 2010 Conceptual Framework for U.S. Mexico Discussions on Colorado River Cooperative Actions Minute 318 December 2010 Adjustment of Delivery Schedules for Water Allotted to Mexico as a matter of international comity as a Result of Infrastructure Damage

4 Background 2007 Colorado River Interim Guidelines for Lower Basin s and Coordinated Operations for Lakes Powell and Mead Proactive System Management Reductions of Water Allocation for Lower Basin States Volumes Based on Lake Mead Elevations Only Pertains to Unites States

5 Hydrology Sub-Workgroup United States and Mexico Participants Explore Alternatives Mexico Triggers Mexico Triggers

6 Alternative Trigger Mechanisms 1. Reservoir Storage Triggers 2. Climate-Based Triggers 3. Combination Storage/Climate Triggers 4. Unique Index Value Colorado River Index (CRI) Key Assumptions Historical Hydrology Fixed and Values Time Horizon

7 APPROACH Colorado River Simulation System (CRSS) Multiple Runs using Index Sequential Method Rule-Based Policy Modifications Reductions of Mexico Demands During Increases of Mexico Demands During Data Objects Control Panel Internal RiverWare Analyses External GPAT Analysis

8 Scenarios Studied 100+ Exploratory Scenario Runs 38 Unique Scenarios Reported 18 Storage Triggered Scenario 5 Climate Triggered Scenarios 10 Storage/Climate Combination Triggered Scenarios 5 Index Triggered Scenarios

9 1,219.6 ft 25.9 maf 1,200 ft Flood Control or Quantified Condition 22.9 maf 1,195 ft 1,170 ft 1,145 ft 12 Lake Mead Trigger Scenarios 1,105 ft Domestic or ICS Condition Normal or ICS Condition 15.9 maf 11.9 maf (7/20/2011, 46% of live capacity) 1,075 ft 1,050 ft 1,025 ft 1,000 ft 895 ft Not to scale Condition Condition Condition Dead Pool (2.0 maf) 9.4 maf 7.5 maf 5.8 maf 4.3 maf 0 maf

10 1,219.6 ft 6 Combined Storage Trigger Scenarios Lake Mead Lake Powell Threshold Threshold < 10% > 90% < 20% > 80% < 30% > 70% < 40% > 60% < 50% > 50% < 43% > 64.5% Not to scale

11 Climate Indicator Trigger Standardized Precipitation Index (SPI) Fits a Precipitation Data to a Gamma Distribution 7-Year SPI 7 Best Correlated with Reservoir Elevations 3.0 Probability Distribution of SPI Values using Precipitation Data SPI Values Category > 2.00 Extremely wet to 1.99 Very wet to 1.49 Moderately wet 0.0 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% to 0.99 Near normal to Moderately dry to Severely dry -3.0 < Extremely dry

12 5 Standardized Precipitation Index (SPI 7 ) Scenarios Threshold Threshold < 0 > 0 < -0.5 > -0.5 < -1.0 > -1.0 < -1.5 > -1.5 < -2.0 > -2.0 SPI Values Category > 2.00 Extremely wet 1.50 to 1.99 Very wet 1.00 to 1.49 Moderately wet to 0.99 Near normal to Moderately dry to Severely dry < Extremely dry

13 10 Combination Storage AND/OR Precipitation Scenarios Condition Threshold SPI 7 > 0 AND Mead > 1145 SPI 7 < 0 AND Mead < 1075 SPI 7 > +0.5 AND Mead > 1145 SPI 7 < -0.5 AND Mead < 1075 SPI 7 > +1.0 AND Mead > 1145 SPI 7 < -1.0 AND Mead < 1075 SPI 7 > +1.5 AND Mead > 1145 SPI 7 < -1.5 AND Mead < 1075 SPI 7 > +2.0 AND Mead > 1145 SPI 7 < -2.0 AND Mead < 1075 SPI 7 > 0.0 OR Combined > 70% SPI 7 < 0.0 OR Combined < 30% SPI 7 > +0.5 OR Combined > 70% SPI 7 < -0.5 OR Combined < 30% SPI 7 > +1.0 OR Combined > 70% SPI 7 < -1.0 OR Combined < 30% SPI 7 > +1.5 OR Combined > 70% SPI 7 < -1.5 OR Combined < 30% SPI 7 > +2.0 OR Combined > 70% SPI 7 < -2.0 OR Combined < 30%

14 Colorado River Index Developed through a Principal Component Analysis of: SPI 7 Lake Powell Storage Lake Mead Storage Combined Lake Powell and Lake Mead Storage Lake Powell Water Year Release Equalization Release from Lake Powell Natural Flow at Lee s Ferry Gaging Site Basin-wide Consumptive Use

15 5 Colorado River Index Scenarios SPI PowellStor MeadStor ComStor LFNatFlow PowellRel Equalization ConUse SPI PowellStor MeadStor ComStor LFNatFlow PowellRel Equalization ConUse CCC = A B C D E A = SSS CC ii MMM MMM B = 8.59 MMM LL ii MMM MMM C = 2.70 MMM D = E = PP ii MMM MMM 2.22 MMM CC ii MMM MMM 1.01 MMM

16 Evaluation of Scenarios Determine Probability of s and to Mexico for Compare with Projections for the United States Determine Frequency of Alignment of and Conditions

17 40% 35% Probability of vs. Probability of United States Status 30% Probability of 25% 20% 15% Less Equitable 10% 5% 0% 0% 2% 4% 6% 8% 10% 12% 14% 16% 18% 20% Probability of Less Equitable

18 Probability of Alignment or or United States 1 Mexico United States Mexico Alignment = = Both Countries in Either Country in 1 Σ{1,6,8,3,5} Normal Normal United States Mexico Alignment = = Both Countries in Either Country in 2 Σ{2,4,5,7,8}

19 80% Probability of vs. Probability of Probability of 70% 60% 50% 40% 30% 20% 10% United States A1-A4 A5-A8 A9-A12 A13-A17 A18 B1-B5 C1-C5 C6-C10 D1-D4 D5 0% 0% 10% 20% 30% 40% 50% 60% Probability of

20 Primary Task of the Hydrology Workgroup is Completed Decision Makers Have a Full Suite of Options Stay Tuned for the Results Questions?