Basin Hydrology, Reservoir Operations and 2020 Hydrograph October - PowerPoint PPT Presentation

Basin Hydrology, Reservoir Operations and 2020 Hydrograph October 21, 2019

Upper Basin Storage and Inflow Water Year 2020 Basin Storage Forecasted Unregulated Inflow 76% As of Issued October 2, 2019 10/18/19 90% Forecast Percent of Reservoir Average 1 (kaf) Fontenelle 1,024 95 Flaming Gorge 1,375 95 Blue Mesa 880 92 Navajo 810 75 85% Powell 9,500 88 1 Percent of average based on the period of record from 1981-2010. 81% 54% Available online at: www.usbr.gov/uc/water/basin/index.html 2

Lake Powell Inflow 3

Lake Powell Monthly Release 4

Lake Powell & Lake Mead Operational Table Operational Tiers for Water/Calendar Year 2020 1 3,618.56 ft Jan 1, 2020 Projection 1,089.40 ft Jan 1, 2020 Projection 1 Lake Powell and Lake Mead operational tier determinations were based on August 2019 24-Month Study projections and will be documented in the draft 2020 AOP. 5

Release Scenarios 6

Monthly Release Volumes 7

Powell Elevations Most Probable End of CY 2020 Most Probable End of CY 2019 Projection: 3,618.12 feet (56% full) Projection: 3,609.83 feet (53% full) Min/Max Range: 3,585.4 to 3,657.97 feet Min/Max Range: 3,609.8 to 3,610.4 feet 8

Mead Elevations Most Probable End of CY 2019 Projection: 1,088.59 feet (41% full) Min/Max Range: 1,088.4 to 1,088.8 feet Most Probable End of CY 2020 Projection: 1,081.25 feet (39% full) Min/Max Range: 1,081.25 to 1,121.36 feet 9

Glen Canyon Power Plant Planned Unit Outage Schedule for Water Year 2020 Unit Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Glen Canyon Power Plant unit 2019 2019 2019 2020 2020 2020 2020 2020 2020 2020 2020 2020 Number 1 outage schedule for WY2020 2 3 4 5 6 7 8 Units 5 5/6 6/8 6 6 6 6 6 6 6 6 6 Available Capacity 16,800 20,500/ MOST 16,800 20,500 20,400 20,400 20,400 20,600 20,900 20,900 20,800 20,800 / 22,520 28,000 (cfs) Capacity MAX 1,060 1,160 1,420 1,330 1,170 1,250 1,220 1,320 1,280 1,330 1,320 1,310 (kaf/month) Max (kaf) 1 625 625 750 1,210 1,070 1,130 1,010 1,000 1,050 1,190 1,270 963 11.89 Most (kaf) 2 8.23 625 625 750 760 675 700 630 630 650 750 835 600 9.0 Min (kaf) 1 625 625 750 860 750 800 710 710 750 850 900 670 (updated 10-09-2019) 1 Projected release, based on Oct 2019 Min and Max Probable Inflow Projections and 24-Month Study model runs 2 Projected release, based on October 2019 Most Probable Inflow Projections and 24-Month Study model runs 10

September 2019 Hourly Releases 11

October 2019 Hourly Releases 12

November 2019 Hourly Releases 13

December 2019 Hourly Releases 14

Lake Powell Release Temperatures

Grand Canyon Water Temperatures

Lake Powell Reservoir Temperature Profile Penstock

Historical Dissolved Oxygen

Dissolved 5.0 mg/l Oxygen Penstock Comparison 10/12/2005 11/2/2005 12/9/2005 5.0 mg/l Penstock Penstock 5.0 mg/l 5.0 mg/l

Dissolved Oxygen, September 2005 Lake Powell Dissolved Oxygen, September 2005 elevation, Ft 3600 6 7 5 5 6 5 7 4 3 5 3 4 4 3 4 3550 2 2 2 3 2 5 4 2 6 5 2 2 4 2 3 3 3500 3 3 3 3 2 3 Penstock mg/L 4 4 4 4 4 3 5 3450 5 5 8 5 4 7 5 2 3400 6 3 4 5 4 5 4 3350 4 5 3 4 3300 2 4 1 3250 0 4 3200 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 Km Upstream from Dam

Dissolved Oxygen, December 2005 Lake Powell Dissolved Oxygen, December 2005 elevation, Ft 3600 3550 8 3500 Penstock 6 8 mg/L 6 6 3450 11 4 4 6 4 10 3400 2 9 8 2 4 6 4 8 3350 7 6 4 3300 5 4 4 3 3250 2 1 3200 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 Km Upstream from Dam

Questions and Discussion