Donnell Lake water level — California

California · USGS · reading Aug 31, 2026, 12:45 AM (UTC-07:00) Provisional

Donnell Lake in California was last measured at 4,865.12 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 (−31.2 ft). This reading is provisional and subject to revision.

Current reading Donnell Lake · California
Pool elevation
4,865.12 ft

Datum NGVD29 · provisional, subject to revision. (Why datum matters →)

% of conservation pool full
Not reported
Storage
44,190 acre-ft
Recent trend
↓Falling

−31.2 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.

4914.7ft4865.1ftJun 2 – Aug 31

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).

Not for navigation or safety decisions (why →)

Source: USGS site 11292600, 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 230 sq mi of contributing watershed.

The dam behind Donnell Lake

Donnell Lake is held back by Donnells , a concrete structure , standing 317 ft high and running 750 ft along its crest , built across Middle Fork Stanislaus River in Tuolumne County , near Sonora . It was completed in 1958 , and is owned by South San Joaquin Irrigation District (a public utility owner) , to a design credited to George E. Goodall Co..

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;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 175 ft wide. Its outlet works use tainter (radial)5.

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 satisfactory — no deficiencies recognised for expected loading. That assessment is dated 09/29/2023.

At its normal pool the reservoir covers about 418 acres. NID records a maximum storage of 65,000 acre-ft against a normal storage of 64,500 acre-ft. Its maximum discharge capacity is 43,800 cubic feet per second. It is regulated by DWR, Safety of Dams.

Dam facts: National Inventory of Dams record CA00264 , 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 Donnell Lake compares nearby

4 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.

Lakes nearest to Donnell Lake, with current level and distance.
Lake State Level Distance
Beardsley Lake CA 3,347.38 ft 17 km
Cherry Lake CA 4,683.53 ft 40 km
Lake Eleanor CA 4,654.41 ft 40 km
Hetch Hetchy Reservoir a Hetch Hetchy CA 3,780.90 ft 45 km
Leviathan Mine Pond 1 CA 7,039.45 ft 49 km
Leviathan Mine Pit Flow CA 7,044.71 ft 49 km

Frequently asked questions

What is the current water level of Donnell Lake?
As of Aug 31, 2026, 12:45 AM (UTC-07:00), the pool elevation was 4,865.12 ft (datum NGVD29), provisional and subject to revision. See the trend chart above for the recent direction.
Is Donnell 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 11292600, 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.