Tulloch Reservoir water level — California
Tulloch Reservoir in California was last measured at 508.91 ft (datum NGVD29), as of Aug 31, 2026, 1:15 AM (UTC-07:00) (USGS Water Services). Over its recent trend window the level has been rising (+1.6 ft). This reading is provisional and subject to revision.
- % of conservation pool full
- Not reported
- Storage
- 65,610 acre-ft
- Recent trend
- ↑Rising
+1.6 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 11299995 · USACE SPK/Tulloch, 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 980 sq mi of contributing watershed. USACE's continuous storage record for this project begins in 1991 (2 tracked series for this project).
The dam behind Tulloch Reservoir
Tulloch Reservoir is held back by Tulloch , a concrete structure , standing 205 ft high and running 1,914 ft along its crest , built across Stanislaus River in Calaveras County , near Knights Ferry . 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;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 280 ft wide. Its outlet works use tainter (radial)7.
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 1,260 acres. NID records a maximum storage of 68,400 acre-ft against a normal storage of 67,000 acre-ft. Its maximum discharge capacity is 13,900 cubic feet per second. It is regulated by DWR, Safety of Dams.
Dam facts: National Inventory of Dams record CA00265 , 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 Tulloch Reservoir compares nearby
None of the 5 nearby lakes with a current trend are rising right now — this lake's movement looks specific to its own operation rather than shared regional conditions.
Nearby lakes
The six nearest published lakes by centroid distance (great-circle) — cross-state neighbors included.
| Lake | State | Level | Distance |
|---|---|---|---|
| New Melones Reservoir | CA | 1,009.84 ft | 11 km |
| Don Pedro Reservoir | CA | 794.88 ft | 25 km |
| Farmington Lake-Pool | CA | 124.47 ft | 29 km |
| New Hogan Lake Pool | CA | 671.35 ft | 36 km |
| New Exchequer Dam / Lake Mcclure | CA | 796.87 ft | 44 km |
| Sjr Par-Pardee-Mokelumne River | CA | — | 48 km |
Frequently asked questions
- What is the current water level of Tulloch Reservoir?
- As of Aug 31, 2026, 1:15 AM (UTC-07:00), the pool elevation was 508.91 ft (datum NGVD29), provisional and subject to revision. See the trend chart above for the recent direction.
- Is Tulloch Reservoir 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 11299995 · USACE SPK/Tulloch, 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.