Beardsley Lake water level — California
Beardsley Lake in California was last measured at 3,347.38 ft (datum NGVD29), as of Aug 31, 2026, 12:45 AM (UTC-07:00) (USGS Water Services). Over its recent trend window the level has been falling (−20.0 ft). This reading is provisional and subject to revision.
- % of conservation pool full
- Not reported
- Storage
- 64,750 acre-ft
- Recent trend
- ↓Falling
−20.0 ft over the trend window
Recent trend
Readings this station published between Jun 2, 2026 and Aug 31, 2026 — a 89-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: USGS site 11292800, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for this lake →
About this gauge's record
This site's drainage basin covers approximately 309 sq mi of contributing watershed.
The dam behind Beardsley Lake
Beardsley Lake is held back by Beardsley , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 284 ft high and running 1,000 ft along its crest , built across Middle Fork Stanislaus River in Tuolumne County , near Sonora . It was completed in 1957 , and is owned by South San Joaquin Irrigation District (a public utility owner) , to a design credited to Tudor-Goodenough.
Its recorded primary purpose is hydroelectric — releases follow generation schedules, so the level can move on a daily cycle that has nothing to do with drought . It also serves hydroelectric;recreation;flood risk reduction.
It is founded on rock. Its spillway is gated, so the operator can hold the pool above the spillway crest and meter what leaves. The spillway opening is 174 ft wide. Its outlet works use tainter (radial)4.
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. Its most recent condition assessment was fair: sound under normal loading, though a rare or extreme event could expose a deficiency. That assessment is dated 09/29/2023.
At its normal pool the reservoir covers about 720 acres. NID records a maximum storage of 97,800 acre-ft against a normal storage of 97,500 acre-ft. Its maximum discharge capacity is 90,000 cubic feet per second. It is regulated by DWR, Safety of Dams.
Dam facts: National Inventory of Dams record CA00263 , filed by Federal Energy Regulatory Commission — U.S. Army Corps of Engineers, public domain. Water levels above come from USGS Water Services and are a separate source. (How this dam was matched to this gauge →)
How Beardsley Lake compares nearby
5 of 6 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 |
|---|---|---|---|
| Donnell Lake | CA | 4,865.12 ft | 17 km |
| Cherry Lake | CA | 4,683.53 ft | 29 km |
| Lake Eleanor | CA | 4,654.41 ft | 31 km |
| Hetch Hetchy Reservoir a Hetch Hetchy | CA | 3,780.90 ft | 38 km |
| New Melones Reservoir | CA | 1,009.84 ft | 48 km |
| Tulloch Reservoir | CA | 508.91 ft | 59 km |
Frequently asked questions
- What is the current water level of Beardsley Lake?
- As of Aug 31, 2026, 12:45 AM (UTC-07:00), the pool elevation was 3,347.38 ft (datum NGVD29), provisional and subject to revision. See the trend chart above for the recent direction.
- Is Beardsley Lake 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 USGS site 11292800, 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.