Lake Sonoma-Pool water level — California
Lake Sonoma-Pool in California was last measured at 449.04 ft (datum NGVD29), as of Aug 31, 2026, 8:00 AM (UTC+00:00) (USACE CWMS Data). Over its recent trend window the level has been falling (−1.0 ft).
- % of conservation pool full
- Not reported
- Storage
- 239,756 acre-ft
- Recent trend
- ↓Falling
−1.0 ft over the trend window
Recent trend
Readings this station published between Jun 2, 2026 and Jun 23, 2026 — a 20-day window — downsampled for display.
Data: USGS Water Services (waterservices.usgs.gov) and USACE CWMS Data (cwms-data.usace.army.mil), retrieved 2026-08-31. Both public domain (a work of the U.S. Government, 17 U.S.C. §105).
Source: USACE SPK/Lake Sonoma-Pool, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for this lake →
The dam behind Lake Sonoma-Pool
Lake Sonoma-Pool is held back by Warm Springs Dam (also recorded as Lake Sonoma) , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 356 ft high and running 3,000 ft along its crest , built across DRY CREEK in Sonoma County , near HEALDSBURG . It was completed in 1983 , and is owned by USACE - San Francisco District (a federal owner) .
Its recorded primary purpose is flood risk reduction — the pool is drawn down between storms so there is empty space waiting for the next flood, which is why this level can fall in dry weather and climb sharply after rain . It also serves flood risk reduction;recreation;hydroelectric;water supply.
It is founded on rock;soil, with a earth core. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. The spillway opening is 100 ft wide. Its outlet works use slide (sluice gate)2.
NID classes it high hazard potential. That describes what a failure would cost downstream — loss of life would be expected — and says nothing about how likely a failure is, or what condition the dam is in.
At its normal pool the reservoir covers about 2,600 acres. NID records a maximum storage of 449,000 acre-ft against a normal storage of 245,000 acre-ft. Its maximum discharge capacity is 29,600 cubic feet per second.
Dam facts: National Inventory of Dams record CA10303 , filed by US Army Corps of Engineers — U.S. Army Corps of Engineers, public domain. Water levels above come from USACE CWMS Data and are a separate source. (How this dam was matched to this gauge →)
How Lake Sonoma-Pool compares nearby
4 of 5 nearby lakes with a current trend are also falling right now.
Nearby lakes
The six nearest published lakes by centroid distance (great-circle) — cross-state neighbors included.
| Lake | State | Level | Distance |
|---|---|---|---|
| Clear Lake a Lakeport | CA | 1,324.02 ft | 36 km |
| Lake Mendocino-Pool | CA | 735.78 ft | 55 km |
| Indian Valley Reservoir a Clearlake Oaks | CA | 1,459.25 ft | 57 km |
| Black Butte Lake | CA | — | 132 km |
| Black Butte Lake-Pool | CA | 446.33 ft | 135 km |
| San Andreas Lake a Dam | CA | 443.80 ft | 135 km |
Frequently asked questions
- What is the current water level of Lake Sonoma-Pool?
- As of Aug 31, 2026, 8:00 AM (UTC+00:00), the pool elevation was 449.04 ft (datum NGVD29). See the trend chart above for the recent direction.
- Is Lake Sonoma-Pool full right now?
- Its managing agency does not publish a %-of-conservation-pool-full figure for this lake, so we show the bare level rather than estimate one.
- Where does this data come from?
- From USACE SPK/Lake Sonoma-Pool, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00).
More in California
See every lake tracked in California, or read the methodology behind these figures.