New Jersey lake & reservoir water levels

8 lakes tracked · 8 with a current elevation reading · USGS Water Services + USACE CWMS Data

New Jersey has 8 lakes and reservoirs tracked here — 8 with a current elevation reading, from USGS Water Services and USACE CWMS Data. Sort the table by level, storage, %-full, or trend, then open any lake for its full elevation-with-datum, trend sparkline, storage, and source-and-vintage stamp. Figures are provisional readings for reference — not for navigation or safety decisions.

Statewide totals New Jersey · USGS + USACE
Lakes tracked
8

8 report a current pool-elevation reading; the rest report storage only.

With elevation reading
8
With %-full figure
0

All New Jersey lakes

Every lake tracked in New Jersey. Click a column heading to sort, or filter by name. Elevation lakes are listed before storage-only lakes; a missing figure always shows "not reported," never an estimate.

New Jersey lakes, elevation lakes first, by name.
Datum Trend
Boonton Reservoir at Boonton 305.45 NGVD29 →Steady
Greenwood Lake at Awosting 618.45 NAVD88 ↓Falling
Lake Tappan at Old Tappan 55.10 NGVD29 →Steady
Oradell Reservoir at Oradell 23.04 NGVD29 ↓Falling
Spruce Run Reservoir at Clinton 262.70 NGVD29 ↑Rising
Swimming River Reservoir 35.06 NGVD29 ↑Rising
Wanaque Reservoir at Wanaque 295.64 NGVD29 ↑Rising
Woodcliff Lake at Hillsdale 94.74 NGVD29 →Steady

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).

Every New Jersey lake in detail

Each lake tracked in New Jersey has its full record here — current reading, recent trend, and the dam behind it where the National Inventory of Dams has one. Use the table above to jump to a lake, or read straight through.

Boonton Reservoir at Boonton

USGS · reading Aug 31, 2026, 4:00 AM (UTC-04:00) Provisional

Pool elevation
305.45 ft

Datum NGVD29

% of conservation pool full
Not reported
Storage
Not reported
Recent trend
→Steady

0.0 ft over the trend window

306.3ft303.4ftJun 2 – Aug 31

Boonton Reservoir at Boonton is held back by Boonton Dam , a masonry structure of cut stone or block , standing 120 ft high and running 2,150 ft along its crest , built across Rockaway River in Morris County . It was completed in 1905 , and is owned by Jersey City Municipal Utilities Authority . 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 satisfactory — no deficiencies recognised for expected loading. National Inventory of Dams record NJ00354 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01380900, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Boonton Reservoir at Boonton →

Greenwood Lake at Awosting

USGS · reading Aug 31, 2026, 3:15 AM (UTC-04:00) Provisional

Pool elevation
618.45 ft

Datum NAVD88

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

−0.2 ft over the trend window

618.9ft618.3ftJun 2 – Aug 31

Greenwood Lake at Awosting is held back by Greenwood Lake Dam , a concrete structure , standing 17 ft high and running 270 ft along its crest , built across Wanaque River in Passaic County , near Netcong . It was completed in 1928 , and is owned by Division of Parks and Forestry . Its recorded primary purpose is recreation — holding a stable pool through the season is an operating goal, so a level well off normal in summer is unusual rather than routine. 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. National Inventory of Dams record NJ00187 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01383000, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Greenwood Lake at Awosting →

Lake Tappan at Old Tappan

USGS · reading Aug 31, 2026, 3:30 AM (UTC-04:00) Provisional

Pool elevation
55.10 ft

Datum NGVD29

% of conservation pool full
Not reported
Storage
Not reported
Recent trend
→Steady

−0.1 ft over the trend window

55.4ft54.6ftJun 2 – Aug 31

Lake Tappan at Old Tappan is held back by Lake Tappan Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 34 ft high and running 590 ft along its crest , built across Hackensack River in Bergen County , near Old Tappan . It was completed in 1966 , and is owned by SUEZ Water New Jersey, Inc. . 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 satisfactory — no deficiencies recognised for expected loading. National Inventory of Dams record NJ00246 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01376950, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Lake Tappan at Old Tappan →

Oradell Reservoir at Oradell

USGS · reading Aug 31, 2026, 3:15 AM (UTC-04:00) Provisional

Pool elevation
23.04 ft

Datum NGVD29

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

−0.2 ft over the trend window

23.7ft14.1ftJun 2 – Aug 31

Oradell Reservoir at Oradell is held back by Oradell Reservoir Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 25 ft high and running 402 ft along its crest , built across Hackensack River in Bergen County , near New Milford . It was completed in 1922 , and is owned by SUEZ Water New Jersey, Inc. . 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 fair: sound under normal loading, though a rare or extreme event could expose a deficiency. National Inventory of Dams record NJ00258 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01378480, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Oradell Reservoir at Oradell →

Spruce Run Reservoir at Clinton

USGS · reading Aug 31, 2026, 3:45 AM (UTC-04:00) Provisional

Pool elevation
262.70 ft

Datum NGVD29

% of conservation pool full
Not reported
Storage
Not reported
Recent trend
↑Rising

+1.3 ft over the trend window

262.7ft259.4ftJun 2 – Aug 31

Spruce Run Reservoir at Clinton is held back by Spruce Run Reservoir Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 93 ft high and running 5,400 ft along its crest , built across Spruce Run in Hunterdon County , near Clinton . It was completed in 1964 , and is owned by New Jersey Water Supply Authority . 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. National Inventory of Dams record NJ00132 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01396790, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Spruce Run Reservoir at Clinton →

Swimming River Reservoir

USGS · reading Aug 31, 2026, 3:15 AM (UTC-04:00) Provisional

Pool elevation
35.06 ft

Datum NGVD29

% of conservation pool full
Not reported
Storage
Not reported
Recent trend
↑Rising

+2.8 ft over the trend window

35.2ft32.1ftJun 2 – Aug 31

Swimming River Reservoir is held back by Swimming River Reservoir Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 45 ft high and running 2,400 ft along its crest , built across Robins Swamp Brook in Monmouth County , near Red Bank . It was completed in 1901 , and is owned by New Jersey-American Water Company . 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 satisfactory — no deficiencies recognised for expected loading. National Inventory of Dams record NJ00082 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01407498, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Swimming River Reservoir →

Wanaque Reservoir at Wanaque

USGS · reading Aug 31, 2026, 3:15 AM (UTC-04:00) Provisional

Pool elevation
295.64 ft

Datum NGVD29

% of conservation pool full
Not reported
Storage
Not reported
Recent trend
↑Rising

+1.6 ft over the trend window

298.3ft293.0ftJun 2 – Aug 31

Wanaque Reservoir at Wanaque is held back by Raymond Dam , 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 1,603 ft along its crest , built across Wanaque River in Passaic County . It was completed in 1928 , and is owned by North Jersey District Water Supply Commission . 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 satisfactory — no deficiencies recognised for expected loading. National Inventory of Dams record NJ00213 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01386990, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Wanaque Reservoir at Wanaque →

Woodcliff Lake at Hillsdale

USGS · reading Aug 31, 2026, 4:00 AM (UTC-04:00) Provisional

Pool elevation
94.74 ft

Datum NGVD29

% of conservation pool full
Not reported
Storage
Not reported
Recent trend
→Steady

+0.0 ft over the trend window

95.6ft87.8ftJun 2 – Aug 31

Woodcliff Lake at Hillsdale is held back by Woodcliff Lake Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 38 ft high and running 1,500 ft along its crest , built across Pascalk Brook in Bergen County , near Hillsdale . It was completed in 1906 , and is owned by SUEZ Water New Jersey, Inc. . 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 satisfactory — no deficiencies recognised for expected loading. National Inventory of Dams record NJ00247 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01377450, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Woodcliff Lake at Hillsdale →

Frequently asked questions

How many lakes and reservoirs in New Jersey are tracked here?
8, of which 8 report a current pool-elevation reading. The rest report storage only, or lack a fresh reading and are not published.
Which New Jersey lakes report a %-full figure?
None of New Jersey's lakes in this dataset currently have a source-provided %-full figure — we show the bare level rather than estimate one.
Where does the data come from?
USGS Water Services and USACE CWMS Data, both public domain. See the methodology page for the exact endpoints and update cadence.

Explore

Read the methodology behind these figures, or search all lakes nationally from the home page.