Pilarcitos Lake water level — California

California · USGS · reading Aug 31, 2026, 1:00 AM (UTC-07:00) Provisional

Pilarcitos Lake in California was last measured at 679.13 ft (datum NGVD29), as of Aug 31, 2026, 1:00 AM (UTC-07:00) (USGS Water Services). Over its recent trend window the level has been falling (−1.1 ft). This reading is provisional and subject to revision.

Current reading Pilarcitos Lake · California
Pool elevation
679.13 ft

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

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

−1.1 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.

681.1ft679.1ftJun 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 11162618, 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 4 sq mi of contributing watershed.

The dam behind Pilarcitos Lake

Pilarcitos Lake is held back by Pilarcitos , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 103 ft high and running 520 ft along its crest , built across Pilarcitos Crk in San Mateo County , near Half Moon Bay . It was completed in 1866 , and is owned by City and County of San Francisco (a local government owner) .

Its recorded primary purpose is water supply — delivering water to its customers comes first, so drawdown here follows demand as much as it follows rainfall .

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 09/12/2024.

At its normal pool the reservoir covers about 109 acres. NID records a maximum storage of 3,100 acre-ft. Its maximum discharge capacity is 1,244 cubic feet per second. It is regulated by DWR, Division of Safety of Dams.

Dam facts: National Inventory of Dams record CA00128 , filed by California — 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 Pilarcitos 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 Pilarcitos Lake, with current level and distance.
Lake State Level Distance
San Andreas Lake a Dam CA 443.80 ft 6 km
Lower Crystal Springs Reservoir CA 272.37 ft 7 km
San Antonio Reservoir CA 455.56 ft 51 km
Calaveras Reservoir CA 725.83 ft 53 km
Del Valle Dam & Reservoir CA 695.18 ft 60 km
Los Banos Reservoir CA 296.00 ft 133 km

Frequently asked questions

What is the current water level of Pilarcitos Lake?
As of Aug 31, 2026, 1:00 AM (UTC-07:00), the pool elevation was 679.13 ft (datum NGVD29), provisional and subject to revision. See the trend chart above for the recent direction.
Is Pilarcitos 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 11162618, 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.