1. Water Resources Development Commission (HB 2661) Water Supply & Demand Working Group – Water Supply Sub Committee Major Existing Supply Data and Studies Wednesday, January 5, 2011

2. Existing Supply Data and Studies Demand and Supply Assessments for Phoenix, Tucson and Prescott AMA’s (ADWR, 2010) Demand and Supply Assessments for Phoenix, Tucson and Prescott AMA’s (ADWR, 2010) Water Use Data for Pinal AMA and Santa Cruz AMA’s (ADWR, 2009) Water Use Data for Pinal AMA and Santa Cruz AMA’s (ADWR, 2009) Water Use Data for GW Basins outside of AMA’s (ADWR, 2008 and USGS, 2009) Water Use Data for GW Basins outside of AMA’s (ADWR, 2008 and USGS, 2009)

3. Colorado River Basin Water Supply and Demand Study (Reclamation/CR Basin States, in Draft) Colorado River Basin Water Supply and Demand Study (Reclamation/CR Basin States, in Draft) North Central Arizona Water Supply Study Report of Findings (Reclamation, 2006) North Central Arizona Water Supply Study Report of Findings (Reclamation, 2006) Augmentation Alternatives for the Sierra Vista Sub-watershed, Arizona, Appraisal Report (Reclamation, 2007) Augmentation Alternatives for the Sierra Vista Sub-watershed, Arizona, Appraisal Report (Reclamation, 2007) Central Yavapai Highlands Water Resources Management Study (Reclamation, 2009) Central Yavapai Highlands Water Resources Management Study (Reclamation, 2009)

4. Existing Supply Data and Studies Vulnerability/ Sustainability Issues Water Level Change Analysis for Arizona Water Atlas Vol. 9 (ADWR, in Draft) Water Level Change Analysis for Arizona Water Atlas Vol. 9 (ADWR, in Draft) Recent Variability in Reservoir Levels and Historic Changes in Precipitation from Arizona Water Atlas Vol. 1 (ADWR, 2010 revised) Recent Variability in Reservoir Levels and Historic Changes in Precipitation from Arizona Water Atlas Vol. 1 (ADWR, 2010 revised) Vulnerability Assessment Categories, Criteria and Metrics for Arizona Water Atlas Vol. 9 (ADWR, in Draft) Vulnerability Assessment Categories, Criteria and Metrics for Arizona Water Atlas Vol. 9 (ADWR, in Draft) Vulnerability assessment of climate-induced water shortage in Phoenix (Gober and Kirkwood, 2009)

5. Demand and Supply Assessments for Phoenix, Tucson and Prescott AMA’s Historical Water Demand and Supply Water Characteristics for 1985-2006 Historical Water Demand and Supply Water Characteristics for 1985-2006 Multiple Demand and Supply Projections out to 2025 Multiple Demand and Supply Projections out to 2025

9. Water Use Data for Pinal and Santa Cruz AMA’s Historical Water Demand and Supply Water Characteristics for 1985-2006 Historical Water Demand and Supply Water Characteristics for 1985-2006 Assessment Reports in Draft Assessment Reports in Draft

10. January 2009 version – subject to change

12. Water Use Data for GW Basins outside of AMA’s GW Withdrawals (USGS, 2009) for 1991-2007 GW Withdrawals (USGS, 2009) for 1991-2007 SW Diversions (ADWR, 2008) for 1991-2007 SW Diversions (ADWR, 2008) for 1991-2007 Effluent Demand data from 13 basins c. 2005 (ADWR, 2009) Effluent Demand data from 13 basins c. 2005 (ADWR, 2009) Sector # Basins with Data Municipal46 Agricultural26 Industrial27 Sector Municipal16 Agricultural15 Industrial8

13. Groundwater Withdrawn for Municipal Demand 46 GW Basins with Data

14. Surface Water Diverted for Agricultural Demand 15 GW Basins with Data

15. Colorado River Basin Water Supply and Demand Study (Reclamation/CR Basin States, in Draft) Define current and future imbalances in water supply and demand (2010-2060) Define current and future imbalances in water supply and demand (2010-2060) Geographic Scope Geographic Scope Current Colorado River Contractors Current Colorado River Contractors Mainstem Mainstem Central Arizona Central Arizona Other Rural Areas Other Rural Areas North Central Arizona North Central Arizona Central Yavapai Highlands Central Yavapai Highlands Upper San Pedro Upper San Pedro

16. Colorado River Basin Water Supply and Demand Study Unmet Demand = Unmet Demand = Demand – (Locally Available Supplies) Locally Available Supplies have been estimated for each of the areas of interest Locally Available Supplies have been estimated for each of the areas of interest Mainstem: Current Colorado River Entitlement Mainstem: Current Colorado River Entitlement Central Arizona: AMA Assessment Data Central Arizona: AMA Assessment Data Other Rural Areas: Data from Reclamation Studies Other Rural Areas: Data from Reclamation Studies

17. Water Level Change Analysis for Arizona Water Atlas Vol. 9 (ADWR, in Draft) Statistical data on groundwater level changes from the late 1980’s/early 1990’s to the mid to late 2000’s Statistical data on groundwater level changes from the late 1980’s/early 1990’s to the mid to late 2000’s Water level change statistics compiled for each groundwater basin and subbasin in the state Water level change statistics compiled for each groundwater basin and subbasin in the state Accompanying map shows water level changes (positive, negative, or zero) over time period Accompanying map shows water level changes (positive, negative, or zero) over time period

19. Count of Positive WL Changes1513 Mean Positive WL Change25.1(Feet) Mean Positive WL Change Rate1.5(Feet/year) Median Positive WL Change12.2(Feet) Count of Negative WL Changes2842 Mean Negative WL Change-23.8(Feet) Mean Negative WL Change Rate-1.4(Feet/year) Median Negative WL Change-17.4(Feet) Count of All WL Changes4396 Mean Of All WL Changes-6.7(Feet) Median Of All WL Changes-4.7(Feet) Summary of Statewide GW Level Changes

22. Recent Variability in Reservoir Levels and Historic Changes in Precipitation from Arizona Water Atlas Vol. 1 Reservoir Storage Volumes on Colorado, Salt/Verde, and Gila Rivers (1980-2008) Reservoir Storage Volumes on Colorado, Salt/Verde, and Gila Rivers (1980-2008)

24. Recent Variability in Reservoir Levels and Historic Changes in Precipitation from Arizona Water Atlas Vol. 1 Temperature and Precipitation Data by Planning Area (1930-2002) (non-AMA’s) Temperature and Precipitation Data by Planning Area (1930-2002) (non-AMA’s)

26. Recent Variability in Reservoir Levels and Historic Changes in Precipitation from Arizona Water Atlas Vol. 1 Winter Precipitation Departures from Average (1000-1988) Winter Precipitation Departures from Average (1000-1988) Woodhouse et al. (2010) argue that the mid– 12th-century drought, whose severity and duration exceeded anything in the historical record, can be used to exemplify the severe droughts that may occur in the future Woodhouse et al. (2010) argue that the mid– 12th-century drought, whose severity and duration exceeded anything in the historical record, can be used to exemplify the severe droughts that may occur in the future

28. Vulnerability Assessment Categories, Criteria and Metrics for Arizona Water Atlas Vol. 9 (ADWR, in Draft) Categories Categories A. Physical Supply Constraints B. Current Demand Exceeds Supply C. Sensitivity to Extended Drought or Shortage D. Legal Considerations E. Environmental Impacts

29. Vulnerability Assessment Categories, Criteria and Metrics for Arizona Water Atlas Vol. 9 A) Physical Supply Constraints A1Dependency on non-renewable supply A2Groundwater is geologically limited A3Declining water levels in demand centers A4 Water Budget Deficit or Water Deficit Assessment A5Insufficient infrastructure (current) A6Regional water quality exceedences A7 Contamination restricts use as drinking water supplies A8Groundwater data needs

30. Vulnerability Assessment Categories, Criteria and Metrics for Arizona Water Atlas Vol. 9 B) Current Demand Exceeds Supply B1Current high rate of growth B2Meeting current demand has been identified as a problem B3Large number of inadequacy determinations (outside AMAs; all reasons) B4 Lack of a regional or local water resource management authority B5 Demand data are lacking in any given sector (Environment, M&I or Agriculture)

31. Vulnerability Assessment Categories, Criteria and Metrics for Arizona Water Atlas Vol. 9 C) Sensitivity to Extended Drought or Shortage C1 Dependency on surface water or drought sensitive groundwater C2Drought-caused supply problems in the past C3Insufficient long-term storage (dams, recharge) C4Weak Drought Preparedness (Community Water System Drought Plan Evaluation) C5Historic drought trends/model predictions show climate impacts

32. Vulnerability Assessment Categories, Criteria and Metrics for Arizona Water Atlas Vol. 9 D) Legal Considerations D1Low priority Colorado River rights D2Groundwater Transportation D3Unquantified Federal Reserved Right Claims D4Endangered species habitat impacts access to supply

33. Vulnerability Assessment Categories, Criteria and Metrics for Arizona Water Atlas Vol. 9 E) Environmental Values E1 Presence of a perennial/intermittent stream in the basin E2 Potential for pumping to impact stream E3Instream Flow rights E4Subsidence (active or potential) E5 Impaired reaches affect use for environment E6 Environmental water needs identified as an issue E7 Unknown vulnerability (It is unknown what the impacts of other sector’s demand will be on the environment in a basin)

34. Vulnerability Assessment of Climate-Induced Water Shortage in Phoenix (Gober and Kirkwood, 2009) Published in Proceedings of the National Academy of Sciences Uses a water-balance simulation model to assess the vulnerability to long-term water shortage Considers runoff scenarios for the Salt/Verde system (19% to 123% of historical mean) and mainstream of the Colorado River (61% to 118%) Considered growth limits, land-use change and groundwater management strategies

36. Vulnerability Assessment of Climate-Induced Water Shortage in Phoenix (Gober and Kirkwood, 2009) Results and Conclusions Wide range of uncertainty about how much water will be available for from the Colorado and Salt/Verde systems Designing a system to supply enough water for current consumption rates in the most pessimistic climate change scenarios would be very expensive and perhaps, physically impossible Designing a system for a best guess case could leave vulnerable to water shortage with little time to adapt.