1 Water Supply Conditions Update
Steven R. Ritchie
Assistant General Manager, Water
October 5, 2026
First Report of the New Water Year
October 5, 2026 Reservoir Storage
2 Storage as of:
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 282,600 360,360 77,760 78.4% 78.3%
Cherry 238,600 273,345 34,745 87.3% -
Eleanor 16,730 27,100 10,370 61.7% -
Water Bank 569,973 570,000 27 100.0% 99.6%
Total Tuolumne Storage 1,107,903 1,230,805 122,902 90.0% - Local System
Calaveras 53,422 96,670 43,248 55.3% -
San Antonio 42,621 53,266 10,645 80.0% -
Crystal Springs 40,526 68,953 28,427 58.8% -
San Andreas 16,308 18,675 2,367 87.3% -
Pilarcitos 1,720 3,125 1,405 55.0% -
Total Local Storage 154,597 240,689 86,092 64.2% -
Total System Storage 1,262,500 1,471,494 208,994 85.8% 79.4% Total without water bank 692,527 901,494 208,967 76.8% - 2 Water bank storage reported by HHWP for 10/04/2026
3 Local storage is the date's 8AM storage value taken from USGS data 5The ratio of median storage for this day over maximum storage capacity. Median storage for this day is based on historical storage data from years 1991 - 2020 5-Oct-2026
1 Upcountry storage is the date's 8AM storage value taken from USGS data 4 Hetch Hetchy maximum storage is with drum gates activated. Cherry and Eleanor maximum storage is with flashboards in. All maximum storages taken from rating curve.
Other
California
Reservoirs
3 California Drought Monitor
4 Hetch Hetchy Precipitation
5 Upcountry 6-station Precipitation Index as of
September 30, 2026
12-Month Median Total: 30.92 inches
Current Year Total: 30.46 inches
6 Annual Comparison:
Upcountry 6-station Precipitation Index as of
October 4, 2026
12-Month Median Total: 30.92 inches
Current Year Total: 0.00 inches
7 Annual Comparison:
Bay Area 7-station Precipitation Index
as of September 30, 2026
12-Month Median Total: 23.35 inches
Current Year Total: 26.11 inches
8 Annual Comparison:
Bay Area 7-station Precipitation Index
as of October 4, 2026
12-Month Median Total: 23.35 inches
Current Year Total: 0.00 inches
9 Annual Comparison:
Water Available to the City
10 California
Precipitation
Forecast
11 Upcountry
Precipitation
Forecast
12 Total Deliveries
13