Mariposa-Pool water level — California

California · USACE · reading Aug 31, 2026, 7:00 AM (UTC+00:00)

Mariposa-Pool in California was last measured at 367.88 ft (datum NGVD29), as of Aug 31, 2026, 7:00 AM (UTC+00:00) (USACE CWMS Data). Over its recent trend window the level has been falling (−0.3 ft).

Current reading Mariposa-Pool · California
Pool elevation
367.88 ft

Datum NGVD29. (Why datum matters →)

% of conservation pool full
Not reported
Storage
24 acre-ft
Recent trend
↓Falling

−0.3 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.

372.7ft372.4ftJun 2 – Jun 23

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: USACE SPK/Mariposa-Pool, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for this lake →

About this gauge's record

USACE's continuous storage record for this project begins in 1983 (2 tracked series for this project).

The dam behind Mariposa-Pool

Mariposa-Pool is held back by Mariposa Dam (also recorded as Mariposa Reservoir) , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 88 ft high and running 1,330 ft along its crest , built across MARIPOSA CREEK in Mariposa County , near LE GRAND . It was completed in 1948 , and is owned by USACE - Sacramento 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;hydroelectric.

It has 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 260 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.

At its normal pool the reservoir covers about 510 acres. NID records a maximum storage of 21,500 acre-ft against a normal storage of 4,300 acre-ft. Its maximum discharge capacity is 30,000 cubic feet per second.

Dam facts: National Inventory of Dams record CA10107 , 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 Mariposa-Pool 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.

Lakes nearest to Mariposa-Pool, with current level and distance.
Lake State Level Distance
Owens-Pool CA 348.53 ft 5 km
Bear-Pool CA 343.97 ft 11 km
Burns-Pool CA 265.81 ft 15 km
Eastman Lake-Pool CA 466.66 ft 15 km
Hensley Lake-Pool CA 546.20 ft 31 km
New Exchequer Dam / Lake Mcclure CA 796.87 ft 34 km

Frequently asked questions

What is the current water level of Mariposa-Pool?
As of Aug 31, 2026, 7:00 AM (UTC+00:00), the pool elevation was 367.88 ft (datum NGVD29). See the trend chart above for the recent direction.
Is Mariposa-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/Mariposa-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.