Reservoirs in Minnesota

199 of 2,252 graded Minnesota lakes (9%) are man-made reservoirs in the USACE National Inventory of Dams. 30 carry a High or Significant hazard rating.

Why these Minnesota reservoirs were built

121

Recreation

Other

Flood Risk Reduction

Fish and Wildlife Pond

Hydroelectric

Water Supply

Tailings

Grade Stabilization

199

Total reservoirs

275,043

Total surface acres

4,277,530

Normal storage (ac-ft)

High or Significant hazard

All 199 Minnesota reservoirs (by surface area)

Reservoir	County	Grade	Surface area	Year built	Purpose	Hazard
Lake Winnibigoshish	Cass	B	68,000 ac	1884	Water Supply	Significant
Otter Tail Lake	Otter Tail	A	14,745 ac	1936	Other	Low
Pokegama Lake	Itasca	A	13,000 ac	1884	Recreation	Significant
Gull Lake	Cass	A	13,000 ac	1912	Recreation	Low
Pokegama Lake	Itasca	A	13,000 ac	1884	Recreation	Significant
Pelican Lake	Crow Wing	A	8,253 ac	1938	Other	Low
Miltona Lake	Douglas	A	5,724 ac	1937	Recreation	Low
Green Lake	Kandiyohi	A	5,560 ac	1938	Recreation	Low
Rush Lake	Otter Tail	B	5,233 ac	1937	Recreation	Low
Whiteface Reservoir	St. Louis	F	4,800 ac	1922	Hydroelectric	Low
Big Pine Lake	Otter Tail	B	4,644 ac	1937	Recreation	Low
Ida Lake	Douglas	A	4,426 ac	1937	Recreation	Low
Pelican Lake	Otter Tail	A	3,962 ac	1938	Recreation	Low
Deer Lake	Itasca	A	3,958 ac	1938	Recreation	Low
Height of Land Lake	Becker	C	3,500 ac	1938	Recreation	Low
Koronis Lake	Stearns	C	3,034 ac	1989	Recreation	Low
Ten Mile Lake	Otter Tail	B	2,208 ac	1937	Recreation	Low
Wabana Lake	Itasca	A	2,186 ac	1940	Fish and Wildlife Pond	Low
Fall Lake	Lake	C	2,173 ac	1989	Recreation	Low
Big Birch Lake	Todd	B	2,112 ac	1992	Fish and Wildlife Pond	Low
Little Pine Lake	Otter Tail	B	2,100 ac	1933	Recreation	Low
Potato Lake	Hubbard	A	2,100 ac	1939	Recreation	Low
Potato Lake	Hubbard	C	2,100 ac	1939	Recreation	Low
Pelican Lake	St. Louis	C	2,050 ac	2002	Recreation	Low
Sturgeon Lake	St. Louis	A	2,050 ac	1936	Recreation	Low
White Earth Lake	Becker	A	1,990 ac	1937	Recreation	Low
Pomme de Terre Lake	Grant	D	1,948 ac	1936	Recreation	Low
Devil Track Lake	Cook	B	1,873 ac	1987	Recreation	Low
Long Lake	Hubbard	A	1,863 ac	1949	Recreation	Low
Diamond Lake	Kandiyohi	D	1,660 ac	1932	Recreation	Low
Pine Mountain Lake	Cass	A	1,612 ac	1936	Recreation	Low
Pine Mountain Lake	Cass	A	1,612 ac	1936	Recreation	Low
Many Point Lake	Becker	A	1,588 ac	1938	Recreation	Low
Washburn Lake	Cass	A	1,554 ac	1936	Recreation	Low
Blue Lake	Crow Wing	A	1,510 ac	1936	Recreation	Low
Roosevelt Lake	Cass	A	1,510 ac	1936	Recreation	Low
Maple Lake	Polk	C	1,477 ac	1942	Recreation	Low
Byllesby Lake	Dakota	F	1,430 ac	1911	Hydroelectric	High
Blanche Lake	Otter Tail	A	1,352 ac	1938	Recreation	Low
Thunder Lake	Cass	A	1,347 ac	1934	Recreation	Low
Thunder Lake	Cass	A	1,347 ac	1934	Recreation	Low
Sylvan Lake	Cass	A	1,280 ac	1913	Hydroelectric	High
Knife Lake	Kanabec	F	1,277 ac	1983	Recreation	Significant
Little Kandiyohi Lake	Kandiyohi	F	1,237 ac	1941	Recreation	Low
Whitewater Lake	St. Louis	A	1,233 ac	1954	Water Supply	Significant
Rose Lake	Otter Tail	A	1,177 ac	1937	Recreation	Low
Round Lake	Becker	A	1,100 ac	1938	Recreation	Low
Lower Prior Lake	Scott	B	1,056 ac	—	—	Low
Bald Eagle Lake	Ramsey	C	1,046 ac	1889	Recreation	Low
Prairie Lake	Otter Tail	B	1,025 ac	1936	Recreation	Low
Wind Lake	Lake	C	1,009 ac	1900	Other	Low
Nest Lake	Kandiyohi	C	1,008 ac	1964	Recreation	Low
Shaokotan Lake	Lincoln	D	994 ac	1917	Other	Low
Clearwater Lake	Clearwater	A	886 ac	1931	Other	Low
Beltrami Lake	Beltrami	A	853 ac	1938	Recreation	Low
Movil Lake	Beltrami	A	853 ac	1938	Recreation	Low
Moses Lake	Douglas	A	824 ac	1937	Other	Low
Eagle Lake	Kandiyohi	C	819 ac	1941	Fish and Wildlife Pond	Low
Orwell Lake	Otter Tail	C	805 ac	1953	Flood Risk Reduction	High
Okabena Lake	Nobles	F	785 ac	1941	Recreation	Low
Ely Lake	St. Louis	A	780 ac	1939	Recreation	Low
Cedar Lake	Wright	A	774 ac	1963	Recreation	Low
Pillager Lake	Cass	A	768 ac	1917	Hydroelectric	High
Rabideau Lake	Beltrami	C	723 ac	1937	Fish and Wildlife Pond	Low
Loon Lake	Jackson	F	707 ac	1935	Recreation	Low
Jefferson Lake	Le Sueur	F	700 ac	1938	Recreation	Low
Lake Jefferson	Le Sueur	D	700 ac	1938	Recreation	Low
Nokay Lake	Crow Wing	C	697 ac	1966	Recreation	Low
Emily Lake	Crow Wing	D	694 ac	1939	Recreation	Low
Ossawinnamakee Lake	Crow Wing	A	662 ac	1937	Recreation	Low
Waukenabo Lake	Aitkin	C	650 ac	1938	Recreation	Low
Wilson Lake	Lake	A	650 ac	1961	Recreation	Low
Collinwood Lake	Wright	D	644 ac	1955	Recreation	Low
Geneva Lake	Douglas	B	635 ac	1936	Recreation	Low
Calhoun Lake	Kandiyohi	B	617 ac	1937	Recreation	Low
Clear Lake	Waseca	F	611 ac	1937	Recreation	Low
Aaron Lake	Douglas	C	611 ac	1964	Recreation	Low
Two Inlets Lake	Becker	B	600 ac	1938	Recreation	Low
Ripple Lake	Aitkin	D	600 ac	1938	Recreation	Low
West Mcdonald Lake	Otter Tail	A	561 ac	1937	Recreation	Low
Cokato Lake	Wright	D	560 ac	—	Other	Low
Fountain Lake	Freeborn	F	555 ac	1911	Recreation	Low
Barrett Lake	Grant	D	532 ac	1937	Recreation	Significant
Long Meadow Lake	Hennepin	F	530 ac	1953	Water Supply	Low
Marion Lake	McLeod	D	520 ac	1948	Other	Low
Sand Hill Lake	Polk	B	510 ac	1956	Recreation	Low
Norway Lake	Cass	C	500 ac	1909	Recreation	Low
Hattie Lake	Cass	B	484 ac	1937	Recreation	Low
Wolf Lake	St. Louis	F	467 ac	1941	Recreation	Low
Blackwater Lake	Itasca	D	464 ac	—	Tailings	Significant
Esquagama Lake	St. Louis	D	453 ac	1937	Recreation	Low
Straight Lake	Becker	B	450 ac	1942	Recreation	Low
Curtis Lake	Yellow Medicine	D	440 ac	2009	Fish and Wildlife Pond	Low
Fish Lake	Kanabec	F	440 ac	1930	Other	Low
State Line Lake	Freeborn	D	425 ac	1930	Fish and Wildlife Pond	Low
Portage Lake	Hubbard	C	422 ac	1938	Recreation	Low
Sibley Lake	Crow Wing	C	418 ac	1937	Recreation	Undetermined
Outlet of Ogechie Lake on the Rum River	Mille Lacs	A	410 ac	1952	—	Low
Little Toad Lake	Becker	A	405 ac	1937	Recreation	Low
Pine Lake	Crow Wing	A	400 ac	1970	Recreation	Low
Cottonwood Lake	Lyon	F	378 ac	1960	Grade Stabilization	Low
Park Lake	Carlton	B	376 ac	1963	Other	Low
Winsted Lake	McLeod	D	376 ac	1954	Recreation	Low
Thomson Reservoir	Carlton	F	375 ac	1907	Hydroelectric	High
Grove Lake	Pope	C	364 ac	1930	Other	Low
Ann Lake	Kanabec	D	363 ac	1966	Fish and Wildlife Pond	Low
North Stanchfield Lake	Isanti	F	363 ac	1939	Recreation	Low
South Stanchfield Lake	Isanti	F	363 ac	1939	Recreation	Low
Eagle Lake	Crow Wing	B	358 ac	1936	Recreation	Low
Elk Lake	Sherburne	D	353 ac	—	Fish and Wildlife Pond	Low
Lory Lake	Isanti	C	341 ac	1962	Fish and Wildlife Pond	Low
Little Waverly Lake	Wright	F	330 ac	1938	Recreation	Low
Hanging Kettle Lake	Aitkin	D	320 ac	1937	Recreation	Low
Marlu Lake	Pope	D	320 ac	1967	Recreation	Low
Emily Lake	Le Sueur	F	315 ac	1939	Recreation	Low
Rice Lake	Hennepin	F	314 ac	1967	Other	Low
Rice Lake	Hennepin	F	314 ac	1967	Other	Low
Peltier Lake	Anoka	F	301 ac	1930	Recreation	Low
Roger Lake	Crow Wing	A	300 ac	1938	Recreation	Undetermined
Lower Orono Lake	Sherburne	F	300 ac	1916	Recreation	High
Beaulieu Lake	Mahnomen	F	300 ac	1922	Fish and Wildlife Pond	Undetermined
Riley Lake	Hennepin	B	296 ac	1958	Recreation	Undetermined
Little Bemidji Lake	Becker	A	290 ac	1938	Recreation	Low
Elmo Lake	Washington	B	281 ac	1981	Flood Risk Reduction	Low
Shakopee Lake	Chippewa	F	261 ac	1976	Flood Risk Reduction	Low
Timm Lake	Yellow Medicine	F	260 ac	1924	Other	Low
Busties Lake	Itasca	A	230 ac	1937	Recreation	Low
Mountain Lake	Cottonwood	F	230 ac	1960	Recreation	Significant
Sleepy Eye Lake	Brown	D	227 ac	1949	Recreation	Low
Smith Lake	St. Louis	A	220 ac	1939	Recreation	Low
Stump Lake	Beltrami	A	201 ac	1907	Hydroelectric	Significant
Pierz Lake	Morrison	C	189 ac	1955	Fish and Wildlife Pond	Low
Eagle Lake	Carver	F	183 ac	1965	Other	Low
Carlos Lake	Douglas	A	183 ac	1993	Recreation	Undetermined
Swartout Lake	Wright	D	171 ac	1941	Recreation	Low
Deer Lake	Wright	D	163 ac	1940	Recreation	Low
Goose Lake	Wright	F	163 ac	1940	Recreation	Low
Del Clark Lake	Yellow Medicine	D	160 ac	1985	Flood Risk Reduction	High
Velvet Lake	Crow Wing	A	160 ac	1937	Recreation	Low
Mill Lake	Becker	B	160 ac	1937	Other	Low
Little Gabbro Lake	Lake	D	154 ac	1924	Recreation	Low
Fox Lake	Beltrami	A	148 ac	1939	Recreation	Undetermined
Watkins Lake	Waseca	F	134 ac	1938	Recreation	Undetermined
Snelling Lake	Hennepin	F	103 ac	1965	Recreation	Low
Balsam Lake	Itasca	B	103 ac	1936	Recreation	Low
Beaver Lake	Steele	B	91 ac	1939	Other	Low
St. Olaf Lake	Waseca	D	90 ac	1940	Recreation	Low
Hill River Lake	Polk	D	88 ac	1950	Flood Risk Reduction	Low
Normandale Lake	Hennepin	C	82 ac	1980	Flood Risk Reduction	Low
Spike Lake	Clearwater	C	80 ac	1938	Fish and Wildlife Pond	Low
Split Rock Reservoir	Pipestone	F	80 ac	1937	Recreation	Significant
George Lake	Martin	F	76 ac	1939	Recreation	Significant
Current Lake Marsh	Murray	F	73 ac	2008	Fish and Wildlife Pond	Low
Round Lake	Ramsey	C	72 ac	1938	Recreation	Low
Phalen Lake	Ramsey	B	72 ac	1938	Recreation	Low
Elkhorn Lake	Kandiyohi	A	72 ac	1969	Flood Risk Reduction	Low
Keller Lake	Ramsey	C	72 ac	1938	Recreation	Low
Wellner-Hageman Reservoir	Brown	D	71 ac	1993	Flood Risk Reduction	Low
Sugar Lake	Itasca	B	67 ac	1980	Other	Low
Muskrat Lake	Becker	B	59 ac	1888	Recreation	Low
Silver Lake	Olmsted	F	58 ac	1935	Recreation	Significant
Long Lake	Becker	A	45 ac	1936	Recreation	Low
St. Clair Lake	Becker	C	45 ac	1936	Recreation	Low
Long Lake	Becker	A	45 ac	1936	Recreation	Low
Silver Lake	Hennepin	C	32 ac	1987	Recreation	Low
Jonathan Lake	Carver	F	31 ac	—	Flood Risk Reduction	Low
Big Woods Lake	Carver	F	31 ac	1989	Flood Risk Reduction	Low
Mcknight Lake	Carver	F	31 ac	—	Flood Risk Reduction	Low
Unnamed Lake	Douglas	F	23 ac	—	Fish and Wildlife Pond	Low
Locke Lake	Anoka	F	23 ac	1956	Recreation	Significant
Laura Lake	Redwood	F	22 ac	1979	Flood Risk Reduction	Significant
Unnamed Lake	St. Louis	C	20 ac	1975	Flood Risk Reduction	High
Grace Lake	Carver	D	19 ac	1968	Flood Risk Reduction	Significant
Mill Pond	Scott	D	16 ac	2000	Recreation	Significant
Alice Lake	Otter Tail	F	15 ac	1921	Hydroelectric	Low
Echo Lake	Carlton	B	10 ac	1988	Fish and Wildlife Pond	Low
Pike Lake	Ramsey	F	9 ac	—	Recreation	Low
Battle Creek Lake	Washington	C	2 ac	1982	Flood Risk Reduction	High
Clear Lake	Stevens	F	—	—	Flood Risk Reduction	Low
Zumbro Lake	Olmsted	D	—	1919	Hydroelectric	High
Thompson Lake	Dakota	F	—	1932	Flood Risk Reduction	Significant
Swan Lake	Itasca	A	—	1967	Other	Low
Perch Lake	Carlton	C	—	—	—	Undetermined
Crow R Mill Pond	Kandiyohi	C	—	1864	Recreation	High
Parley Lake	Carver	F	—	1966	Other	Low
Minerva Lake	Clearwater	B	—	1968	Fish and Wildlife Pond	Low
Wynne Lake	St. Louis	B	—	1944	Other	Low
Jaskari Lake	Carlton	C	—	—	—	Undetermined
Eighth Crow Wing Lake	Hubbard	C	—	1938	Recreation	Low
Deadfish Lake	Carlton	C	—	—	—	Undetermined
Rice Portage Lake	Carlton	C	—	—	—	Undetermined
Marie Lake	Stearns	D	—	1974	Recreation	Low
Faherty Lake	Cass	C	—	1970	Other	Low
Waboose Lake	Becker	C	—	1930	Fish and Wildlife Pond	Low
Champlin Mill Pond	Hennepin	D	—	2017	Recreation	Significant
St. Patrick Lake	Becker	C	—	1953	Fire Protection, Stock, Or Small Fish Pond	Low
Hoot Lake	Otter Tail	B	—	1913	Hydroelectric	Low
Bella Lake	Nobles	F	—	1971	Flood Risk Reduction	Low
Crow River Mill Pond	Kandiyohi	B	—	1864	Recreation	High

Frequently Asked Questions

How many reservoirs are in Minnesota?

199 of 2,252 graded Minnesota lakes (9%) are man-made reservoirs in the USACE National Inventory of Dams. 30 are rated High or Significant hazard, meaning failure would put downstream lives or property at substantial risk. The oldest matched dam dates to 1864.

What's the largest reservoir in Minnesota?

The largest matched reservoir in Minnesota is Lake Winnibigoshish in Cass County at 68,000 acres of normal surface area, impounded by the Winnibigoshish Dam - Dike 1 (completed 1884).

What's the difference between a reservoir and a natural lake?

A reservoir is a body of water impounded by a man-made dam — typically built for flood control, hydroelectric power, water supply, irrigation, or recreation. A natural lake formed without human intervention, usually from glacial scouring, volcanic activity, or river meandering. Reservoirs typically have shoreline that fluctuates with seasonal water level management, while natural lakes have more stable shorelines. The USACE National Inventory of Dams classifies every regulated dam in the United States, which is how we identify which LakeGrade lakes are actually reservoirs.

What does the hazard class mean?

USACE assigns each dam a hazard potential classification based on what would happen downstream if the dam failed — NOT how likely the dam is to fail. "Low" hazard means dam failure would cause no probable loss of life and only low economic loss. "Significant" means probable loss of life is unlikely but appreciable economic damage would occur. "High" means probable loss of life and significant economic damage. The classification is about consequence, not condition. Many High-hazard dams are perfectly safe; they're rated High because populated areas have grown downstream over time.

Where does this reservoir data come from?

Every reservoir record on this page is matched to the USACE National Inventory of Dams (NID), the federal database of all dams ≥25 ft tall or impounding ≥50 acre-feet, plus any dam that poses a Significant or High hazard regardless of size. The NID is published by the U.S. Army Corps of Engineers and updated annually. Surface area, storage capacity, dam height, and hazard classification come directly from NID records.

Data source

Reservoir data from the USACE National Inventory of Dams (NID), the federal database of all regulated dams. Dam attributes (height, year completed, storage capacity, hazard class) are matched to LakeGrade lakes by proximity and dam-name similarity. Some lakes may be reservoirs that aren't matched if the dam record uses a name substantially different from our lake name.