Colorado River Basin Water Supply Outlook Lake Powell Lake Mead La Nina Years ? ! ? Good ? Bad ? Good - Water Year 2011 Bad – Water Year 2012 Upper Colorado River Basin Lake Powell Lake Mead Lower Colorado River Basin Upper Colorado River Basin Lake Powell Lake Mead Lower Colorado River Basin Colorado River Basin Water Supply Outlook 2012 Final Forecast State of the System (1999-2012) 1 Colorado River Basin Water Supply Outlook ● April to June 2012 Inflow Into Lake Powell – 2.36 MAF (33% of Normal – 3rd lowest on record [1909 to 2011]). (April to June Observed 2011 Inflow Into Lake Powell – 12.89 MAF (162% of Normal). ● Water Year 2012 Inflow Into Lake Powell – y6 MAF (51% of Normal) (Water Year 2011 Inflow into Lake Powell – 15.97 MAF [139% of Normal]). ● Water Year 2012 Release from Lake Powell – 9.46 MAF Release to the Lower Basin (1.23 MAF “Equalization” Carryover from Water Year 2011 plus 8.23 MAF minimum objective release per 2007 Interim Guidelines). ● Lake Powell and Lake Mead Storage will generally decline through 2013. Colorado River Basin Water Supply Outlook Colorado River Basin Water Supply Outlook First Shortage Elevation Colorado River Basin Water Supply Outlook Total Reservoir System Contents: 37.1 MAF or 62% (As of May 7, 2012) Total Reservoir System Contents Lake Powell Last Year: Lake Mead 31.6 MAF or 53% Colorado River Basin Water Supply Outlook LAKE POWELL Capacity – 24.5 MAF 05/07/2012 - 64% full Contents 15.5 MAF Elevation – 3,636’ Glen Canyon Dam Page Colorado River Basin Water Supply Outlook LAKE MEAD Capacity - 26 MAF 05/07/2012 - 53% full Contents – 13.9 MAF Elevation – 1,123’ Las Vegas Hoover Dam Lower Colorado River Basin Chance of a Shortage or Surplus Source: Bureau of Reclamation Lake Mead Key Operational Elevations – Interim Period 1220’ (95% full) FLOOD CONTROL OR QUANTIFIED SURPLUS (“70R”) 1200’ (84% full) DOMESTIC SURPLUS 1145’ (56% full) NORMAL OPERATIONS 1075’ (34% full) 400 KAF SHORTAGE (333 KAF to U.S.) (320 KAF to Arizona) Minimum Power Pool and Bottom of First SNWA Intake 1050’ (27% full) 500 KAF SHORTAGE (417 KAF to U.S.) (400 KAF to Arizona) 1025’ (21% full) 600 KAF SHORTAGE (500 KAF to U.S.) (480 KAF to Arizona) Bottom of Second SNWA Intake 1000’ (16% full) Minimum Mead Intake RECONSULTATION Elevation 915’ (2% full) (For Additional Shortages) Top of Dead Storage 895’ (0% full) What About Next Year? La Nina Year ? ! ? El Nino Year ? ! ? El Nino La Nina What About Next Year? La Nina Year ? ! ? El Nino Year ? ! ? El Nino La Nina El Nino La Nina What About Next Year? La Nina Year ? ! ? El Nino Year ? ! ? The Earth’s Water As A Sphere Diameter of the Water Sphere 860 Miles 321 million cubic miles of water Source: USGS Water Science for Schools: http://ga.water.usgs.gov/edu/eatrhhowmuch.html.