Preparing for the Future Near-Term Shortage and Long-Term Challenges

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1 Preparing for the Future Near-Term Shortage and Long-Term Challenges Coconino Plateau Watershed Partnership June 26, 2015 Dennis Rule Manager, CAGRD

2 Central Arizona Project 336-mile aqueduct stretches from Lake Havasu to Tucson 14 pumping plants lift water nearly 3,000 feet 8 siphons, 3 tunnels Lake Pleasant/New Waddell Dam Annually delivers approx. 520 billion gallons (1.6 million acre-feet) Delivery of Colorado River water began in 1985

3 Historical Colorado River Flow 25 Unregulated Colorado River Inflow into Lake Powell ( ) of the last 15 years ( ) had below average Colorado River flow Flow (MAF) Mean = Year

4 Probability of Shortage (before Miracle May ) Year Probability of Shortage Probability of Tier 1 Shortage Probability of Tier 2 Shortage Probability of Tier 3 Shortage % 33% 0% 0% % 71% 4% 0% % 45% 28% 1% % 36% 24% 10% % 29% 23% 14% Source: BOR May month study

5 Miracle May May 2015 precipitation in Upper Colorado River watershed was extraordinary Many weather stations recorded % of average precipitation Projected April July inflows into Lake Powell increased from 2 MAF to 5.0 MAF June forecast for January 1, 2016 Lake Mead water elevation is now above 1,081, an increase of 5 from May forecast Usage/diversions dropped throughout basin Probability of 2016 shortage now negligible, improved outlook for 2017

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7 Probability of Shortage (after Miracle May ) Year Probability of Shortage Probability of Tier 1 Shortage Probability of Tier 2 Shortage Probability of Tier 3 Shortage 2016 N% 0% 0% 0% % 47% 0% 0% % 46% 19% 0% % 40% 21% 5% % 34% 20% 9% Source: BOR June month study

8 What Happens During a Shortage? The Secretary of the Interior reduces the amount of Colorado River water available to Arizona, Nevada and Mexico The amount of reduction depends on the elevation of Lake Mead Within Arizona, the reduction in the near term will be to CAP

9 Shortage Sharing Agreement Basin States agreement in 2006 on conjunctive management of Lakes Powell and Mead and shortage sharing in the Lower Basin Adopted by Secretary in 2007 Effective through water year 2026 Renegotiation to start by 2020

10 AZ/NV/Mexico Shortage Sharing Arizona, Nevada & Mexico share shortages to the Lower Colorado River Elevation in Lake Mead Shortage Arizona Share Nevada Share Mexico Share < 1, ,000 AF 320,000 AF 13,000 AF 50,000 AF < 1, ,000 AF 400,000 AF 17,000 AF 70,000 AF < 1, ,000 AF 480,000 AF 20,000 AF 125,000 AF If Lake Mead is projected to fall below 1000 elevation, the Secretary will consult with Basin States to discuss further measures

11 2016 Projected CAP Deliveries 1,600,000 Low Other Excess 127 KAF 1,400,000 CAP Delivery Priority 1,200,000 Ag Pool 400 KAF Excess Water 1,000,000 Acre Feet NIA Priority 178 KAF 800, , ,000 Indian Priority 326 KAF M&I Priority 441 KAF High 200,000 0 Priority 3-68 KAF Long-term Contract Water

12 Near-term Tier 1 Shortage Impact Low Other Excess Shortage 1,400,000 Ag Pool Shortage 192 KAF 1,200,000 CAP Delivery Priority Ag Pool 208 KAF 1,000,000 Acre Feet NIA Priority 178 KAF 800, ,000 High 400,000 Indian Priority 326 KAF M&I Priority 441 KAF 200,000 0 Priority 3-68 KAF 320,000 1,600,000

13 Near-term Tier 2 Shortage Impact Low Other Excess Shortage 1,400,000 Ag Pool Shortage 223 KAF 1,200,000 CAP Delivery Priority Ag Pool 77 KAF Acre Feet 1,000,000 NIA Priority 222 KAF 800, ,000 High 400,000 Indian Priority 326 KAF M&I Priority 448 KAF 200,000 0 Priority 3-68 KAF 400,000 1,600,000

14 Near-term Tier 3 Shortage Impact Low Other Excess Shortage 1,400,000 CAP Delivery Priority 1,200,000 Acre Feet 1,000,000 Ag Pool Shortage 300 KAF NIA Priority 219 KAF 800, ,000 High 400,000 Indian Priority 326 KAF M&I Priority 448 KAF 200,000 0 Priority 3-68 KAF 480,000 1,600,000 3,000 AF short to NIA Pool

15 A Risk to All Colorado River Users Without equalization from Lake Powell or corrective action, Lake Mead could fall below elevation 1000 in 5-8 years If Lake Mead falls below 1000 : Southern Nevada Water Authority s ability to withdraw water is impacted Lake Mead has less than 4.5 MAF left in storage (<55% of normal flow) Power generation and efficiency at Hoover Dam is reduced and cavitation or vibration damage is possible

16 Impact on CAP Water Rates While cities will not experience significant cuts in their annual deliveries, shortage will impact CAP Water Delivery Rates Rate = Cost Volume With delivery reductions, CAP must collect fixed costs from a smaller number of customers Reduction of electrical power from Hoover Dam at Lake Mead will cause CAP to use some more expensive power

17 CAP Shortage Management Programs Storage and Recovery -3.4 MAF of underground storage for future recovery for CAP cities Lake Mead Reservoir Protection -Interstate plan targeting 740 KAF of new storage in Lake Mead -CAP s share is 345 KAF by 2017 Innovative Conservation -Interstate funding to conserve 75 KAF to protect Lake Mead/Powell -Conservation research grant program Augmentation -Weather modification projects in the Upper Basin -Local and binational desalination

18 Banking Colorado River Water More than 9 million acre-feet have been recharged in Underground Storage and Groundwater Savings Facilities since 1992 The stored water will increase the reliability of CAP subcontracts and certain onriver and Indian supplies CAP has been working with state agencies, customers and stakeholders to develop a recovery plan for the future retrieval of that stored water

19 CAP is Preparing for the Future Colorado River Basin Working cooperatively with state, regional and national partners to address water supply challenges Supporting water conservation education and training for urban and agricultural customers Participating in efforts to address the gap between Colorado River supplies and anticipated demand Interacting regularly with customers and stakeholders about issues of mutual concern

20 Preparing for the Future Near-Term Shortage and LongTerm Challenges Questions? Dennis Rule