Pennsylvania lake & reservoir water levels

31 lakes tracked · 21 with a current elevation reading · USGS Water Services + USACE CWMS Data

Pennsylvania has 31 lakes and reservoirs tracked here — 21 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 Pennsylvania · USGS + USACE
Lakes tracked
31

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

With elevation reading
21
With %-full figure
0

All Pennsylvania lakes

Every lake tracked in Pennsylvania. 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.

Pennsylvania lakes, elevation lakes first, by name.
Datum Trend
Allegheny Reservoir 1,325.91 NAVD88 555,998 ↓Falling
Beltzville Dam 628.34 NAVD88 43,272 ↑Rising
Chambers Lake 577.88 NGVD29 ↑Rising
Conemaugh Lake 911.01 NAVD88 34,556 ↑Rising
Crooked Creek Lake 843.41 NAVD88 19,118 ↓Falling
East Branch Clarion River Lake 1,652.54 NAVD88 48,599 ↓Falling
F.e. Walter Dam 1,362.67 NAVD88 17,159 ↓Falling
George B. Stevenson Dam 921.96 NGVD29 2,396 →Steady
Glendale Lake 1,427.58 NGVD29 ↓Falling
Jadwin Dam 989.26 NAVD88 373 →Steady
Loyalhanna Creek Lake 923.88 NAVD88 12,288 ↓Falling
Mahoning Creek Reservoir 1,097.53 NAVD88 16,684 ↓Falling
Prompton Dam 1,124.01 NAVD88 3,280 ↓Falling
Seneca Power Upper Reservoir 2,031.57 NAVD88 2,480 ↓Falling
Shenango River Reservoir 893.53 NAVD88 33,887 ↑Rising
Stevenson Dam National Cwms Forecast 921.48 NGVD29 →Steady
Struble Lake 616.98 NAVD88 ↑Rising
Tionesta Creek Reservoir 1,090.61 NAVD88 9,857 ↑Rising
Union City Reservoir on French Creek 1,218.76 NAVD88 138 ↑Rising
Woodcock Creek Lake 1,182.39 NAVD88 5,711 ↑Rising
Youghiogheny River Lake 1,440.42 NAVD88 160,032 ↑Rising
Alvin River. Bush Dam 1,974
Aylesworth Creek Lake 63
Cowanesque Lake 30,601
Curwensville Lake 9,607
Foster Joseph Sayers Dam 31,889
Hammond Lake 9,276
Indian Rock Dam 0
Raystown Lake 515,741
Stillwater Lake 302
Tioga Lake 10,116

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 Pennsylvania lake in detail

Each lake tracked in Pennsylvania 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.

Allegheny Reservoir

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

Pool elevation
1,325.91 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
555,998 acre-ft
Recent trend
↓Falling

−1.1 ft over the trend window

1329.0ft1325.4ftJun 2 – Aug 31

Allegheny Reservoir is held back by Kinzua Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 177 ft high and running 1,916 ft along its crest , built across ALLEGHENY RIVER in Warren County , near WARREN . It was completed in 1965 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is gated, so the operator can hold the pool above the spillway crest and meter what leaves. 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. National Inventory of Dams record PA00105 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03012520 · USACE LRP/Kinzua-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Allegheny Reservoir →

Beltzville Dam

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
628.34 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
43,272 acre-ft
Recent trend
↑Rising

+0.1 ft over the trend window

628.2ft628.0ftJun 2 – Jun 7

Beltzville Dam is held back by Beltzville Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 177 ft high and running 4,560 ft along its crest , built across POHOPOCO CREEK in Carbon County , near PARRYVILLE . It was completed in 1969 , and is owned by USACE - Philadelphia District , to a design credited to ERIK FLOOR & ASSOCIATES, INC. CONSULTING ENGINEERS. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00010 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAP/Beltzville, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Beltzville Dam →

Chambers Lake

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

Pool elevation
577.88 ft

Datum NGVD29

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

+0.2 ft over the trend window

580.0ft577.0ftJun 2 – Aug 31

Chambers Lake is held back by Hibernia (Pa-436f) , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 65 ft high and running 700 ft along its crest , built across BIRCH RUN in Chester County . It was completed in 1994 , and is owned by CHESTER COUNTY WATER RESOURCES AUTHORITY , to a design credited to Ward Associates/USDA NRCS. 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. 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 PA01505 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01480399, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Chambers Lake →

Conemaugh Lake

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

Pool elevation
911.01 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
34,556 acre-ft
Recent trend
↑Rising

+2.0 ft over the trend window

925.5ft902.5ftJun 2 – Aug 31

Conemaugh Lake is held back by Conemaugh Dam , a concrete gravity structure, resisting the reservoir by its own weight alone , standing 144 ft high and running 1,266 ft along its crest , built across CONEMAUGH RIVER in Westmoreland County , near SALTSBURG . It was completed in 1952 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is gated, so the operator can hold the pool above the spillway crest and meter what leaves. 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. National Inventory of Dams record PA00101 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03043500 · USACE LRP/Conemaugh-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Conemaugh Lake →

Crooked Creek Lake

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

Pool elevation
843.41 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
19,118 acre-ft
Recent trend
↓Falling

−0.8 ft over the trend window

866.2ft842.3ftJun 2 – Aug 31

Crooked Creek Lake is held back by Crooked Creek Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 143 ft high and running 1,480 ft along its crest , built across CROOKED CREEK in Armstrong County , near FORD CITY . It was completed in 1940 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00102 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03038500 · USACE LRP/CrookedCreek-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Crooked Creek Lake →

East Branch Clarion River Lake

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

Pool elevation
1,652.54 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
48,599 acre-ft
Recent trend
↓Falling

−7.2 ft over the trend window

1670.3ft1652.5ftJun 2 – Aug 31

East Branch Clarion River Lake is held back by East Branch Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 184 ft high and running 1,725 ft along its crest , built across CLARION RIVER in Elk County , near JOHNSONBURG . It was completed in 1952 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00104 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03027000 · USACE LRP/EastBranch-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for East Branch Clarion River Lake →

F.e. Walter Dam

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
1,362.67 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
17,159 acre-ft
Recent trend
↓Falling

−1.1 ft over the trend window

1370.0ft1368.8ftJun 2 – Jun 7

F.e. Walter Dam is held back by Francis E. Walter Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 239 ft high and running 3,000 ft along its crest , built across LEHIGH RIVER in Luzerne County , near WHITE HAVEN . It was completed in 1961 , and is owned by USACE - Philadelphia District , to a design credited to CENAP. 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. NID records no spillway for it. 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. National Inventory of Dams record PA00008 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAP/FEWalter, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for F.e. Walter Dam →

George B. Stevenson Dam

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
921.96 ft

Datum NGVD29

% of conservation pool full
Not reported
Storage
2,396 acre-ft
Recent trend
→Steady

0.0 ft over the trend window

922.0ft921.9ftJun 2 – Jun 7

George B. Stevenson Dam is held back by George B Stevenson , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 166 ft high and running 1,925 ft along its crest , built across FIRST FORK SINNEMAHONING CREEK in Cameron County . It was completed in 1956 , and is owned by DCNR . 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. 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 PA00914 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Stevenson, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for George B. Stevenson Dam →

Glendale Lake

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

Pool elevation
1,427.58 ft

Datum NGVD29

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

−0.5 ft over the trend window

1428.5ft1427.3ftJun 2 – Aug 31

Glendale Lake is held back by Glendale , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 60 ft high and running 1,800 ft along its crest , built across BEAVERDAM RUN in Cambria County . It was completed in 1960 , and is owned by DCNR . 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. 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 PA00912 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 01541340, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Glendale Lake →

Jadwin Dam

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
989.26 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
373 acre-ft
Recent trend
→Steady

−0.0 ft over the trend window

989.2ft989.2ftJun 2 – Jun 7

Jadwin Dam is held back by General Edgar Jadwin Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 110 ft high and running 1,255 ft along its crest , built across DYBERRY CREEK in Wayne County , near HONESDALE . It was completed in 1960 , and is owned by USACE - Philadelphia District . 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00009 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAP/Jadwin, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Jadwin Dam →

Loyalhanna Creek Lake

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

Pool elevation
923.88 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
12,288 acre-ft
Recent trend
↓Falling

−0.3 ft over the trend window

934.8ft922.6ftJun 2 – Aug 31

Loyalhanna Creek Lake is held back by Loyalhanna Dam , a concrete gravity structure, resisting the reservoir by its own weight alone , standing 120 ft high and running 960 ft along its crest , built across LOYALHANNA CREEK in Westmoreland County , near SALTSBURG . It was completed in 1942 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is gated, so the operator can hold the pool above the spillway crest and meter what leaves. 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. National Inventory of Dams record PA00106 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03046500 · USACE LRP/Loyalhanna-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Loyalhanna Creek Lake →

Mahoning Creek Reservoir

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

Pool elevation
1,097.53 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
16,684 acre-ft
Recent trend
↓Falling

−4.8 ft over the trend window

1125.5ft1097.5ftJun 2 – Aug 31

Mahoning Creek Reservoir is held back by Mahoning Creek Dam , a concrete gravity structure, resisting the reservoir by its own weight alone , standing 162 ft high and running 926 ft along its crest , built across MAHONING CREEK in Armstrong County , near PUTNEYVILLE . It was completed in 1941 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is gated, so the operator can hold the pool above the spillway crest and meter what leaves. 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. National Inventory of Dams record PA00107 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03035500 · USACE LRP/Mahoning-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Mahoning Creek Reservoir →

Prompton Dam

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
1,124.01 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
3,280 acre-ft
Recent trend
↓Falling

−0.5 ft over the trend window

1124.7ft1124.2ftJun 2 – Jun 7

Prompton Dam is held back by Prompton Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 140 ft high and running 1,200 ft along its crest , built across LACKAWAXEN RIVER in Wayne County , near PROMPTON . It was completed in 1961 , and is owned by USACE - Philadelphia District . 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00011 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAP/Prompton, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Prompton Dam →

Seneca Power Upper Reservoir

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

Pool elevation
2,031.57 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
2,480 acre-ft
Recent trend
↓Falling

−15.1 ft over the trend window

2066.5ft2025.0ftJun 2 – Jun 23

Seneca Power Upper Reservoir is held back by Kinzua Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 177 ft high and running 1,916 ft along its crest , built across ALLEGHENY RIVER in Warren County , near WARREN . It was completed in 1965 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is gated, so the operator can hold the pool above the spillway crest and meter what leaves. 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. National Inventory of Dams record PA00105 — U.S. Army Corps of Engineers, public domain.

Source: USACE LRP/SenecaPower-Upper, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Seneca Power Upper Reservoir →

Shenango River Reservoir

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

Pool elevation
893.53 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
33,887 acre-ft
Recent trend
↑Rising

+0.8 ft over the trend window

894.3ft892.4ftJun 2 – Aug 31

Shenango River Reservoir is held back by Shenango Dam , a concrete gravity structure, resisting the reservoir by its own weight alone , standing 68 ft high and running 720 ft along its crest , built across SHENANGO RIVER in Mercer County , near SHARPSVILLE . It was completed in 1965 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00111 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03103400 · USACE LRP/Shenango-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Shenango River Reservoir →

Struble Lake

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

Pool elevation
616.98 ft

Datum NAVD88

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

+0.2 ft over the trend window

617.2ft616.7ftJun 2 – Aug 31

Struble Lake is held back by R G Struble Lake (Pa-431) , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 31 ft high and running 1,500 ft along its crest , built across EAST BRANCH BRANDYWINE CREEK in Chester County . It was completed in 1971 , and is owned by CHESTER COUNTY WATER RESOURCES AUTHORITY , to a design credited to USDA NRCS. 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. 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 PA00621 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 0148064640, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Struble Lake →

Tionesta Creek Reservoir

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

Pool elevation
1,090.61 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
9,857 acre-ft
Recent trend
↑Rising

+0.3 ft over the trend window

1094.2ft1089.1ftJun 2 – Aug 31

Tionesta Creek Reservoir is held back by Tionesta Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 154 ft high and running 1,050 ft along its crest , built across TIONESTA CREEK in Forest County , near TIONESTA . It was completed in 1940 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00110 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03019500 · USACE LRP/Tionesta-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Tionesta Creek Reservoir →

Union City Reservoir on French Creek

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

Pool elevation
1,218.76 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
138 acre-ft
Recent trend
↑Rising

+1.6 ft over the trend window

1228.9ft1216.8ftJun 2 – Aug 31

Union City Reservoir on French Creek is held back by Union City Dam , 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 1,420 ft along its crest , built across FRENCH CREEK in Erie County , near UNION CITY . It was completed in 1971 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00103 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03021518 · USACE LRP/UnionCity-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Union City Reservoir on French Creek →

Woodcock Creek Lake

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

Pool elevation
1,182.39 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
5,711 acre-ft
Recent trend
↑Rising

+0.5 ft over the trend window

1183.5ft1181.2ftJun 2 – Aug 31

Woodcock Creek Lake is held back by Woodcock Creek Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 90 ft high and running 4,650 ft along its crest , built across WOODCOCK CREEK in Crawford County , near MEADVILLE . It was completed in 1973 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00108 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03022550 · USACE LRP/Woodcock-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Woodcock Creek Lake →

Youghiogheny River Lake

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

Pool elevation
1,440.42 ft

Datum NAVD88

% of conservation pool full
Not reported
Storage
160,032 acre-ft
Recent trend
↑Rising

+2.6 ft over the trend window

1443.6ft1435.9ftJun 2 – Aug 31

Youghiogheny River Lake is held back by Youghiogheny Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 184 ft high and running 1,610 ft along its crest , built across YOUGHIOGHENY RIVER in Fayette County , near CONFLUENCE . It was completed in 1944 , and is owned by USACE - Pittsburgh District , to a design credited to CELRP. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00109 — U.S. Army Corps of Engineers, public domain.

Source: USGS site 03077000 · USACE LRP/Youghiogheny-Lake, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Youghiogheny River Lake →

Alvin River. Bush Dam

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
1,974 acre-ft
Recent trend
Not enough recent readings

Alvin River. Bush Dam is held back by Alvin R. Bush Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 165 ft high and running 1,350 ft along its crest , built across KETTLE CREEK in Clinton County , near RENOVO . It was completed in 1962 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00002 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Bush, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Alvin River. Bush Dam →

Aylesworth Creek Lake

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
63 acre-ft
Recent trend
Not enough recent readings

Aylesworth Creek Lake is held back by Aylesworth Creek Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 90 ft high and running 1,270 ft along its crest , built across AYLESWORTH CREEK in Lackawanna County , near EAST JERMYN . It was completed in 1970 , and is owned by USACE - Baltimore District , to a design credited to CENAB, CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00001 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Aylesworth, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Aylesworth Creek Lake →

Cowanesque Lake

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
30,601 acre-ft
Recent trend
Not enough recent readings

Cowanesque Lake is held back by Cowanesque Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 151 ft high and running 3,100 ft along its crest , built across COWANESQUE RIVER in Tioga County , near LAWRENCEVILLE . It was completed in 1980 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA01134 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Cowanesque, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Cowanesque Lake →

Curwensville Lake

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
9,607 acre-ft
Recent trend
Not enough recent readings

Curwensville Lake is held back by Curwensville Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 131 ft high and running 2,850 ft along its crest , built across WEST BRANCH SUSQUEHANNA RIVER in Clearfield County , near CURWENSVILLE . It was completed in 1965 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00003 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Curwensville, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Curwensville Lake →

Foster Joseph Sayers Dam

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
31,889 acre-ft
Recent trend
Not enough recent readings

Foster Joseph Sayers Dam is held back by Foster Joseph Sayers Dam , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 100 ft high and running 6,835 ft along its crest , built across BALD EAGLE CREEK in Centre County , near HOWARD . It was completed in 1969 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00005 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Sayers, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Foster Joseph Sayers Dam →

Hammond Lake

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
9,276 acre-ft
Recent trend
Not enough recent readings

Hammond Lake is held back by Hammond Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 122 ft high and running 6,450 ft along its crest , built across CROOKED CREEK in Tioga County , near TIOGA . It was completed in 1978 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA01133 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Hammond, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Hammond Lake →

Indian Rock Dam

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
0 acre-ft
Recent trend
Not enough recent readings

Indian Rock Dam is held back by York Indian Rock Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 83 ft high and running 1,000 ft along its crest , built across CODORUS CREEK in York County , near YORK . It was completed in 1942 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00007 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Indian Rock, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Indian Rock Dam →

Raystown Lake

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
515,741 acre-ft
Recent trend
Not enough recent readings

Raystown Lake is held back by Raystown Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 225 ft high and running 1,700 ft along its crest , built across RAYSTOWN BRANCH JUNIATA RIVER in Huntingdon County , near HUNTINGDON . It was completed in 1973 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00004 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Raystown, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Raystown Lake →

Stillwater Lake

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
302 acre-ft
Recent trend
Not enough recent readings

Stillwater Lake is held back by Stillwater Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 77 ft high and running 1,700 ft along its crest , built across LACKAWANNA RIVER in Susquehanna County , near FOREST CITY . It was completed in 1960 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA00006 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Stillwater, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Stillwater Lake →

Tioga Lake

USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Pool elevation
Not reported
% of conservation pool full
Not reported
Storage
10,116 acre-ft
Recent trend
Not enough recent readings

Tioga Lake is held back by Tioga Dam , a rockfill embankment — quarried rock placed in compacted layers around a sealing core , standing 141 ft high and running 2,710 ft along its crest , built across TIOGA RIVER in Tioga County , near TIOGA . It was completed in 1978 , and is owned by USACE - Baltimore District , to a design credited to CENAB. 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. Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. 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. National Inventory of Dams record PA01132 — U.S. Army Corps of Engineers, public domain.

Source: USACE NAB/Tioga, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for Tioga Lake →

Frequently asked questions

How many lakes and reservoirs in Pennsylvania are tracked here?
31, of which 21 report a current pool-elevation reading. The rest report storage only, or lack a fresh reading and are not published.
Which Pennsylvania lakes report a %-full figure?
None of Pennsylvania'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.