1 Water Supply Conditions Update
Steven R. Ritchie
Assistant General Manager, Water
May 12, 2025
May 19, 2025 Reservoir Storage
2 Reservoir
Current
Storage1,2,3
Maximum
Storage4
Available
Capacity
Percent of
Maximum
Storage
Normal
Percent of
Maximum
Storage5
(AF) (AF) (AF)
Tuolumne System
Hetch Hetchy 328,300 360,360 32,060 91.1% 75.6%
Cherry 264,700 273,345 8,645 96.8% -
Eleanor 24,790 27,100 2,310 91.5% -
Water Bank 570,000 570,000 0 100.0% 95.2%
Total Tuolumne Storage 1,187,790 1,230,805 43,015 96.5% - Local System
Calaveras 76,859 96,670 19,811 79.5% -
San Antonio 46,176 53,266 7,090 86.7% -
Crystal Springs 45,374 68,953 23,579 65.8% -
San Andreas 15,674 18,675 3,001 83.9% -
Pilarcitos 1,962 3,125 1,163 62.8% -
Total Local Storage 186,045 240,689 54,644 77.3% -
Total System Storage 1,373,835 1,471,494 97,659 93.4% 83.4% Total without water bank 803,835 901,494 97,659 89.2% -
Other
California
Reservoirs
3 California Drought Monitor
4 Hetch Hetchy Precipitation
5 Upcountry 6-station Precipitation Index as of
May 18, 2025
12-Month Median Total: 30.92 inches
Current Year Total: 28.85 inches
6 Annual Comparison:
Bay Area 7-station Precipitation Index
as of May 18, 2025
12-Month Median Total: 23.35 inches
Current Year Total: 22.62 inches
7 Annual Comparison:
Upcountry Snowpack
8 Water Available to the City
9 Tuolumne River Water Available
to the City
10 11
National Precipitation Forecast
Total Deliveries
12