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Water Watch

Clear water wave

About 75% of the District's water supply originates from rainfall on our Mt. Tamalpais watershed and in the grassy hills of west Marin, flowing into the District’s seven reservoirs. The District also supplements its supply with water from the Sonoma County Water Agency (SCWA), which comes from the Russian River system in Sonoma County. The Russian River water supply originates from rainfall that flows into Lake Sonoma and Lake Mendocino. Learn more about our water supply, reservoir levels, and recent rainfall in the tables below. 

Water Production

Week Ending Average Million Gallons Per Day
5/31/2023 21.13
Same Week in 2022 21.46
Supply Source:  
          Reservoirs 10.88
          Same Week in 2022 9.55
          Russian River 10.25
          Same Week in 2022 11.91



Rainfall at Lake Lagunitas (average annual rainfall is 52.65 inches) Inches
7/01/2022 - 5/31/2023 76.94
Same period last year 48.94
Average year-to-date 51.84
Rainfall for last 24 hours 0.00

Summary:  Current rainfall (76.94 inches) is 148.42% of the average rainfall (51.84 inches) for this date.


Reservoir Storage

Alpine, Bon Tempe, Kent, Lagunitas, Nicasio, Phoenix & Soulajule Reservoirs
(total capacity 79,566 acre-feet)
Acre-feet % of Capacity
Storage as of 5/31/2023 78,153 98.22%
Storage for this date last year 69,964 87.93%
Average storage for this date 69,675 87.57%

Summary:  Current storage (78,153 AF) is 112.16% of the average storage (69,675 AF) for this date.

Reservoir Diversion Data

By Reservoir: