Nacimiento Reservoir water level — California

California · USGS · reading Aug 31, 2026, 12:30 AM (UTC-07:00) Provisional

Nacimiento Reservoir in California was last measured at 750.91 ft (datum NGVD29), as of Aug 31, 2026, 12:30 AM (UTC-07:00) (USGS Water Services). Over its recent trend window the level has been falling (−7.3 ft). This reading is provisional and subject to revision.

Current reading Nacimiento Reservoir · California
Pool elevation
750.91 ft

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

% of conservation pool full
Not reported
Storage
Not reported
Recent trend
↓Falling

−7.3 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.

768.0ft750.9ftJun 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 11149300, 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 325 sq mi of contributing watershed.

The dam behind Nacimiento Reservoir

Nacimiento Reservoir is held back by Nacimiento , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 255 ft high and running 1,630 ft along its crest , built across Nacimiento River in San Luis Obispo County , near Bradley . It was completed in 1956 , and is owned by Monterey County Water Resources Agency (a local government owner) .

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;irrigation;recreation;water supply;flood risk reduction.

It is founded on soil. Its spillway is gated, so the operator can hold the pool above the spillway crest and meter what leaves. The spillway opening is 150 ft wide.

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 poor — a deficiency was recognised that needs attention. That assessment is dated 09/29/2023.

At its normal pool the reservoir covers about 5,400 acres. NID records a maximum storage of 470,000 acre-ft against a normal storage of 377,900 acre-ft. Its maximum discharge capacity is 102,400 cubic feet per second. It is regulated by DWR, Safety of Dams.

Dam facts: National Inventory of Dams record CA00812 , 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 Nacimiento Reservoir 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 Nacimiento Reservoir, with current level and distance.
Lake State Level Distance
San Antonio Reservoir CA 741.12 ft 4 km
Los Banos Reservoir CA 296.00 ft 145 km
Alisal Reservoir CA 598.47 ft 151 km
Big Dry Creek Dam CA 400.00 ft 166 km
Friant Dam CA 508.83 ft 174 km
Hensley Lake-Pool CA 546.20 ft 174 km

Frequently asked questions

What is the current water level of Nacimiento Reservoir?
As of Aug 31, 2026, 12:30 AM (UTC-07:00), the pool elevation was 750.91 ft (datum NGVD29), provisional and subject to revision. See the trend chart above for the recent direction.
Is Nacimiento 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 11149300, 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.