1,220'. 3,700'. 3,613. Colorado River Water Supply Report. System Contents: 28.91 MAF. 3/26/18. 2018 Equalization Level
Colorado River Water Supply Report System Contents: 28.36 MAF 4/23/18
35%
Reservoir Capacities (MAF) Reservoir Current Change Maximum Lake Mead 10.47 - 0.23 25.90 12.74 - 0.28 Lake Powell 24.30 Flaming Gorge Reservoir 3.75 3.18 - 0.01 1.70 1.23 - 0.01 Navajo Reservoir Blue Mesa Reservoir 0.50 - 0.04 0.83 0.34 Fontenelle Reservoir 0.12 0.00 Morrow Point Reservoir 0.11 + 0.01 0.12
85%
61%
Lake Powell
3,700’
52%, 12.74 MAF 2018 Equalization Level 3,654’
96%
3,610
Lake Mead 1,220’ 40%, 10.47 MAF 1,085’ Tier 1 Shortage 1,075’
73%
Snowpack Conditions As of 4/24/2018, the current SWE is at 80% (9.8 in) of the long-term median (1981-2010) of the water year to date (12.3 in). When compared to the seasonal long-term average (14.2 in) the current SWE is at 69% of the entire season for the current water year (2018).
Lake Powell Elevations Lake Powell is currently operating under the Upper Elevation Balancing Tier for Water Year 2018. The 2018 April 24-month study determined releases from Lake Powell for the water year will be adjusted up to 9 MAF. All projections from the April 24-month study indicate that Lake Powell releases for Water Year 2019 will follow an Upper Elevation Balancing Tier pattern. For Water Year 2020, the most and maximum probable projections suggest that Lake Powell Releases will again follow an Upper Elevation Balancing Tier pattern. However, the minimum probable projection for Water Year 2020 suggests Lake Powell will operate under a Mid-elevation Release Tier pattern.
Lake Mead Elevations Per the 2007 Guidelines, Lake Mead will be operated under the Normal - Intentionally Created Surplus (ICS) Surplus Condition criterion. Based on the 2018 April 24-Month Study minimum, maximum, and most probable projections, Lake Mead will be above the Tier 1 Shortage trigger elevation of 1,075 ft. at the end of calendar year 2018. This would indicate that Mead would not be in Shortage operations for 2019.
At the end of calendar year 2019, the maximum probable case shows Lake Mead’s elevation above 1,075 ft. The minimum probable case shows the possibility of Lake Mead’s elevation being below 1,075 ft., meaning that 2019 could be operated under Tier 1 Shortage criterion. The most probable case Lake Mead elevation is just below 1,075 ft.; however this does not consider conservation activities in 2018 or 2019. Assuming Arizona conservation of 200 kAF in both 2018 and 2019 under the most probable case, Lake Mead’s elevation is projected to end 2019 above 1,075 ft. to prevent Shortage operations in 2020.
CAWCD Shortage Preparedness: Potential Timeline August 2018: Determination of 2019 Mead Operations
November 2018 – March 2019: Snow Accumulation Season & Runoff Forecasts (significant
signals as early as midFebruary)
October 2018: CAP Compiles 2019 Water Orders
May 2019: Potential for water rate update based on shortage risk
April 2019: Inflow Forecast Update (significant signal for risks for 2020 shortage)
October 2019: CAP compiles 2020 Water Orders
August 2019 Determination of 2020 Mead Operations
January 2020 Mead Operations
CAWCD Shortage Preparedness Steps: May 2018 – January 2020 • Track hydrologic signals and runoff/inflow forecasts • Communicate risks with customers and stakeholders • Work with customers/stakeholders to share information on possible impacts to water orders and deliveries • Work with customers/stakeholders to communicate and discuss possible financial impacts from a shortage and available tools to mitigate those impacts • Outline policy discussions on questions that may stem from shortage operations.
