Water Supply Status & Shortage Outlook. March 2011

Transcription

1 Water Supply Status & Shortage Outlook March 2011

2 CAP Water Supply Source is the Colorado River Arizona s Colorado River apportionment is 2.8 million acre-feet (MAF) per year On-river water users in Arizona consume about 1.2 MAF CAP typically receives about 1.6 MAF of Colorado River water in a normal year

3 Secretary s Role Secretary of the Interior is watermaster for the lower Colorado River Secretary prepares an Annual Operating Plan (AOP) for Colorado River reservoirs AOP establishes water supply conditions for the coming year Normal, Surplus or Shortage based on 2007 Guidelines

4 Reservoir Management 2007 Guidelines provide for coordinated operation of Lake Mead and Lake Powell Annual release from Powell based on Powell and Mead elevations Lake Mead Capacity 1,219.6 ft 25.9 maf 1,145 ft 1,000 ft Surplus Conditions Normal or ICS Surplus Conditions 1,110 ft maf 1,075 ft 60 ft (48% of Live Capacity) Shortage Conditions 1,050 ft Min Power Pool Inactive Pool (7.5 maf) 110 ft 15.9 maf Lower SNWA Intake 895 ft Dead Pool Elevation Dead Pool (2.0 maf) Lake Powell Capacity 3,700 ft 24.3 maf 3,636 ft 3,595 ft 3,575 ft maf (47% of Live Capacity) Mid-Elevation Release Tier 105 ft 3,525 ft Lower Elevation Balancing Tier 3,490 ft Min Power Inactive Pool (4.0 maf) Pool 3,370 ft Dead Pool Dead Pool (1.9 maf) Elevation Not to scale Equalization Tier Upper Elevation Balancing Tier As of May 4, ft 105 ft Equalization Elevation (WY 2008) Not to scale As of May 4, 2008

5 Annual Operating Plan Based on January 1 elevations in Lake Mead and Lake Powell as projected in USBR s August 24-month study e.g.: August month study will project the elevations of Lake Powell and Lake Mead as of January 1, 2012 Those projected elevations will determine reservoir operating conditions for 2012 AOP

6 Lake Mead Operation Surplus: Lake Mead elevation above 1145 Normal: Lake Mead elevation above 1075 and below 1145 Shortage: Lake Mead elevation below 1075 (Note: There are varying types/levels of surplus and shortage)

7 Current Conditions Lake Mead elevation is 1096 (21 above shortage trigger) Reclamation s most recent 24-month study (March 2011) projects Jan. 1, 2012, Lake Mead elevation will be 1111 (36 above shortage trigger) 97% chance for equalization release from Lake Powell in 2011

8 Shortage Outlook Current snowpack is 113% of long-term average Based on the most recent 24-mo. study, shortage is unlikely until at least 2016

9 What Happens During Shortage? Secretary reduces water available to Lower Basin States Amount of reduction depends on elevation of Lake Mead Reduction shared between AZ & NV Arizona reduction shared between CAP & on-river water users of same priority

10 Shortage Guidelines 2007 Guidelines quantify shortage reduction based on Lake Mead elevation: Elevation Shortage to Lower Basin States ,000 AF ,000 AF ,000 AF If Lake Mead is projected to fall below 1000, the Secretary will consult with Basin States to discuss further measures 10

11 AZ/NV Shortage Sharing Arizona and Nevada share shortages to Lower Basin States: Shortage Arizona Share Nevada Share 333,000 AF 320,000 AF 13,000 AF 417,000 AF 400,000 AF 17,000 AF 500,000 AF 480,000 AF 20,000 AF CAP holds junior priority No reductions to California under 2007 Guidelines 11

12 Shortage Sharing in AZ CAP shares shortages proportionally with post-1968 on-river users within Arizona On average, about 90% of Arizona shortage will be borne by CAP and 10% by on-river users Largest shortage to CAP under 2007 Colorado River guidelines is about 440,000 AF 12

13 Shortages within CAP CAP water is distributed based on an internal priority scheme Long-term CAP water supply contracts have priority Three priority types: Municipal & Industrial (M&I) Indian Non-Indian Agricultural (NIA) 13

14 Shortages within CAP M&I and Indian priority contracts share top priority NIA priority water is delivered only after M&I and Indian priority orders have been filled 14

15 Shortages within CAP Water not ordered under long-term CAP contracts is sold as Excess Water Excess Water has its own priority scheme Agricultural Settlement Pool is 1 st priority Remaining Excess Water is distributed in accordance with CAP Access to Excess Policy 15

16 Current CAP Uses In 2011, long-term CAP contractors have scheduled about 925,000 AF That leaves about 700,000 AF that will be delivered as Excess Water, primarily for agriculture and underground storage At present usage rates no shortage defined under the 2007 Guidelines would impact any long-term CAP Indian or M&I contractor

17 Current CAP Uses CAP Delivery Priority Low High Ag Settlement Pool 400,000 Indian 475,000 Other Excess 300,000 M&I 450, CAP Deliveries = MAF

18 Shortage Impact on CAP CAP Delivery Priority Low High Ag Settlement Pool 400,000 Indian 475,000 Other Excess 300,000 M&I 450,000 Shortage Level 1 - Lake Mead below 1075

19 Shortage Impact on CAP CAP Delivery Priority Low High Ag Settlement Pool 340,000 Indian 475,000 Other Excess 300,000 M&I 450,000 Shortage Level 2 - Lake Mead below 1050

20 Shortage Impact on CAP CAP Delivery Priority Low High Ag Settlement Pool 260,000 Indian 475,000 Other Excess 300,000 M&I 450,000 Shortage Level 3 - Lake Mead below 1025

21 Shortage Summary M&I and Indian priority entitlements total 1.05 MAF CAP currently diverts about 1.6 MAF Even level 3 shortage (Mead <1025 ) would not reduce M&I or Indian priority deliveries Shortage would likely cause an increase in CAP delivery rates 21

22 Arizona s Response Conservation Firming Augmentation 22

23 Conservation Saving Colorado River water Reduces risk of shortage to CAP Mitigates impacts of climate change Examples: Brock Reservoir (Drop 2) Yuma Desalting Plant Vegetation management 23

24 Firming Developing temporary water supplies to replace existing supplies during shortage Examples: Underground storage & recovery Dry-year options 24

25 Augmentation Adding new water supplies to what we already have Examples: Importing water from another basin Desalination (ocean, brackish) Weather modification Groundwater development 25