Get Full Government Meeting Transcripts, Videos, & Alerts Forever!
Get email alerts on the Hydrology Update topic
No spam. Unsubscribe anytime.
State Water Board staff: wet north, dry south — early snowpack and storms not predictive of summer flows
Summary
State Water Resources Control Board staff told members on Jan. 5 that northern Sierra precipitation and snowpack are well above average for early January while southern regions remain relatively dry, and cautioned that current winter storms and snowpack are not reliable predictors of summer flows in the Scott and Shasta watersheds.
State Water Resources Control Board staff on Jan. 5 gave an informational update on current hydrologic conditions and staff response, saying northern parts of California had anomalously high precipitation and snowpack for early January 2025 while central and southern regions remained relatively dry.
Jessica Bean of the Board’s Division of Water Rights presented maps and time series showing precipitation and Sierra snowpack indices as of Jan. 4. Bean reported the northern Sierra precipitation index at about 134% of average and statewide snow water equivalent near 106% of normal, with regional contrasts: the central Sierra near 92% and the southern (Tulare) region near 70% of normal.
Bean noted that temperature anomalies have been unusually warm over most of California for the prior three months, which complicates snowpack and runoff expectations. Staff described localized high‑intensity events observed in winter (including thunderstorms, reported tornado activity near the Shasta‑Trinity border, and strong jet‑stream patterns that were producing strong downslope winds and fire‑weather concerns in some southern areas).
Reservoirs and reporting requirements Bean reported that most major water supply reservoirs were at or above average for the date of the report; Folsom was slightly below and Millerton at about 82% of capacity. Donnell Reservoir (referenced later in the Scott/Shasta presentation) was reported at roughly 25,200 acre‑feet, about half of capacity, compared to roughly 8,000 acre‑feet in 2023 and 11,500 acre‑feet in 2024 at a similar point in the water year.
Bean also reminded diverters that annual diversion and use reports for the previous water year are due Feb. 1; staff said statewide compliance for these reports was about 19% at the time of the meeting and encouraged timely filing.
Why this matters Staff emphasized that current winter storms and above‑average early snowpack in parts of the state are not a reliable predictor of summer streamflows. For the Scott and Shasta watersheds staff said most of the snowpack typically accumulates in January–March and that springtime conditions and snow‑water equivalent in April–May will more strongly determine summer availability. The division noted the importance of continuing to gather streamflow and groundwater monitoring data to inform curtailment or cooperative solution decisions later in the season.
Board response Vice Chair Doreen D'Adamo asked staff for an update on the Colorado River Basin at the earliest opportunity. Chair Joaquin Esquivel and other board members agreed to allow a break after the hydrology item so additional commenters could join the platform for the subsequent Scott‑Shasta presentation. Staff said they would continue outreach and provide updates as conditions evolve.
