January 2026 Water Supply Update
Dear Friends and Supporters,
I’m pleased to share good news about our water supply as we move through this rainy season.
A Strong Start to the Water Year
Between July 1, 2025, and January 12, 2026, our watershed received 31.22 inches of rainfall: that’s 132% of our average for this time of year (23.61 inches). Our reservoirs are responding to these winter storms, currently holding 79,466 acre-feet of water, which is nearly 129% of the average storage for this date (61,732 acre-feet).
This productive rainfall means we’re well positioned to enter the dry summer months with more than enough supply to meet our customers’ needs. It’s the kind of water year we hope for, and it reflects the benefits of California’s winter storms.
Planning Ahead: The Next Drought Is Inevitable
While we celebrate this year’s abundant rainfall, we must remember that California’s water future is defined by extremes. Our water supply depends entirely on rainfall—about 75% from our local reservoirs and 25% imported from the Russian River to our north. We receive virtually all of our precipitation during the November-to-March rainy season, and a few consecutive dry years can quickly stress our water supply. We have no groundwater reserves to fall back on and limited access to alternative sources.
This is why strong water years like this one give us both the supply security and the planning opportunity to invest in our water future.
Building Resilience: The Atmospheric River Capture Project
We are currently planning a significant water supply project: the Atmospheric River Capture Project, or ARC, which is a 13-mile pipeline extension designed to transfer excess winter water from the Russian River to our West Marin reservoirs during drought years.
Here’s what makes ARC a smart investment for our community:
- Strategic drought response. We would only activate ARC during drought years when we need it most, which means minimal operational costs during average or above-average rainfall years like this one.
- Capturing abundance, not scarcity. ARC is designed to capture excess winter stormwater during atmospheric river events, California’s most intense rainfall periods, rather than competing for scarce summer supplies.
- Regional benefit. By storing additional water in our reservoirs, we create the potential to support neighboring water agencies during regional droughts, strengthening water security across the North Bay.
The reliable rainfall we’re experiencing this year reminds us what California water abundance looks like, and it underscores why we need infrastructure that can capture and store that abundance for the inevitable dry years ahead.
Looking Forward
As a Director of Marin Water, I’m committed to responsible stewardship of our water resources. That includes appreciating the good water years while preparing for the challenging ones, making strategic investments that serve both our community and our region, and ensuring that Marin’s water supply remains secure for generations to come.
Thank you for your support. If you have questions about our water supply or the ARC project, please don’t hesitate to reach out.
Sincerely,
Ranjiv Khush
Director, Marin Municipal Water District