Ft.

-1

0

+ 1

+ 2

+ 3

+ 4

+ 5

M.

-0.3

0

+ 0.3

+ 0.6

+ 0.9

+ 1.2

+ 1.5

20

DEC

1945

2021

JAN

1946

FEB

1952

MAR

1952

APR

1973

MAY

2017

JUN

2019

JUL

2019

AUG

1947

SEP

1947

OCT

1945

NOV

1945

DEC

1945

1934

2022

JAN

1946

1935

FEB

1952

1936

MAR

1952

1935

APR

1973

1935

MAY

2017

1935

JUN

2019

1935

JUL

2019

1934

AUG

1947

1934

SEP

1947

1934

OCT

1945

1934

NOV

1945

1934

DEC

1945

1934

2023

JAN

1946

1935

FEB

1952

1936

MAR

1952

1935

APR

1973

1935

MAY

2017

1935

LAKE ONTARIO

CHART DATUM 243.3 FEET (74.2 METERS)

Ft.

-1

0

+ 1

+ 2

+ 3

+ 4

+ 5

+ 6

M.

-0.3

0

+ 0.3

+ 0.6

+ 0.9

+ 1.2

+ 1.5

+ 1.8

20

DEC

1986

2021

JAN

1987

FEB

2020

MAR

2020

APR

2020

MAY

2020

JUN

2019

JUL

2019

AUG

2019

SEP

2019

OCT

1986

NOV

1986

DEC

1986

1934

2022

JAN

1987

1935

FEB

2020

1936

MAR

2020

1934

APR

2020

1934

MAY

2020

1934

JUN

2019

1934

JUL

2019

1934

AUG

2019

1934

SEP

2019

1934

OCT

1986

1934

NOV

1986

1934

DEC

1986

1934

2023

JAN

1987

1935

FEB

2020

1936

MAR

2020

1934

APR

2020

1934

MAY

2020

1934

LAKE ERIE

CHART DATUM 569.2 FEET (173.5 METERS)

Ft.

-1

0

+ 1

+ 2

+ 3

+ 4

+ 5

M.

-0.3

0

+ 0.3

+ 0.6

+ 0.9

+ 1.2

+ 1.5

20

DEC

1986

2021

JAN

2020

FEB

1986

MAR

2020

APR

2020

MAY

2020

JUN

2020

JUL

2019

AUG

2020

SEP

2020

OCT

1986

NOV

1986

DEC

1986

1964

2022

JAN

2020

1936

FEB

1986

1926

MAR

2020

1934

APR

2020

1926

MAY

2020

1934

JUN

2020

1934

JUL

2019

1934

AUG

2020

1934

SEP

2020

1934

OCT

1986

1934

NOV

1986

1934

DEC

1986

1964

2023

JAN

2020

1936

FEB

1986

1926

MAR

2020

1934

APR

2020

1926

MAY

2020

1934

LAKE ST. CLAIR

CHART DATUM 572.3 FEET (174.4 METERS)

Ft.

-1

0

+ 1

+ 2

+ 3

+ 4

+ 5

M.

-0.3

0

+ 0.3

+ 0.6

+ 0.9

+ 1.2

+ 1.5

20

DEC

1986

2021

JAN

2020

FEB

2020

MAR

2020

APR

2020

MAY

2020

JUN

2020

JUL

2020

AUG

2020

SEP

1986

OCT

1986

NOV

1986

DEC

1986

2012

2022

JAN

2020

2013

FEB

2020

1964

MAR

2020

1964

APR

2020

1964

MAY

2020

1964

JUN

2020

1964

JUL

2020

1964

AUG

2020

1964

SEP

1986

1964

OCT

1986

1964

NOV

1986

1964

DEC

1986

2012

2023

JAN

2020

2013

FEB

2020

1964

MAR

2020

1964

APR

2020

1964

MAY

2020

1964

LAKES MICHIGAN-HURON

CHART DATUM 577.5 FEET (176.0 METERS)

Ft.

-1

0

+ 1

+ 2

M.

-0.3

0

+ 0.3

+ 0.6

20

DEC

1985

2021

JAN

2020

FEB

2020

MAR

1986

APR

1986

MAY

2019

JUN

2019

JUL

2019

AUG

2019

SEP

2019

OCT

1985

NOV

1985

DEC

1985

1925

2022

JAN

2020

1926

FEB

2020

1926

MAR

1986

1926

APR

1986

1926

MAY

2019

1926

JUN

2019

1926

JUL

2019

1926

AUG

2019

2007

SEP

2019

2007

OCT

1985

1925

NOV

1985

1925

DEC

1985

1925

2023

JAN

2020

1926

FEB

2020

1926

MAR

1986

1926

APR

1986

1926

MAY

2019

1926

LAKE SUPERIOR

CHART DATUM 601.1 FEET (183.2 METERS)

ELEVATIONS REFERENCED TO THE CHART DATUM OF EACH RESPECTIVE LAKE

Superior

602.36

183.60

601.64

183.38

603.31

183.89

1985

600.43

183.01

1925

601.97

183.48

MichHuron

579.27

176.56

579.95

176.77

581.96

177.38

1986

576.28

175.65

1964

578.77

176.41

St.

Clair

574.61

175.14

575.72

175.48

576.84

175.82

1986

571.46

174.18

1934

573.95

174.94

Erie

571.69

174.25

572.93

174.63

573.65

174.85

1986

568.24

173.20

1934

570.93

174.02

Ontario

244.09

74.40

245.60

74.86

246.65

75.18

1945

241.96

73.75

1934

244.59

74.55

NOVEMBER MEAN LAKE LEVELS

(IGLD 1985)

* 2022 Ft.

M.

2021 Ft.

M.

** MAX.

Ft.

M.

Yr.

** MIN.

Ft.

M.

Yr.

** AVG. Ft.

M.

* provisional

** Average, Maximum and Minimum for period 1918-2021

LEGEND

LAKE LEVELS

RECORDED

PROJECTED

AVERAGE **

MAXIMUM **

1985

1985

1973 1973

MINIMUM **

1936

1934

1926 1934

DECEMBER 2022

US Army Corps

of Engineers

Detroit District

MONTHLY BULLETIN OF

LAKE LEVELS FOR THE

GREAT LAKES

Monthly mean water levels for the previous year and the

current year to date are shown as a solid line 

on the hydrographs. A projection for the next

six months is given as a dashed line. This 

projection is based on the present condition 

of the lake basin and anticipated future 

weather. The shaded area shows a range of

possible levels over the next six months 

dependent upon weather variations. Current

and projected levels (solid and dashed lines) 

can be compared with the 1918-2021 average

levels (dotted line) and extreme levels 

(shown as bars with their year of occurrence).

The legend below further identifies the 

information on the hydrographs. 

The levels on the hydrographs are shown in

both feet and meters above (+) or below (-) 

Chart Datum. Chart Datum, also known as 

Low Water Datum, is a reference plane on 

each lake to which water depth and Federal 

navigation improvement depths on navigation 

charts are referred.

All elevations and plots are referenced to the

International Great Lakes Datum 1985 (IGLD 1985). 

IGLD 1985 has its zero base at Rimouski, Quebec 

near the mouth of the St. Lawrence River 

(approximate sea level). 

Visit our website for more information:

https://www.lre.usace.army.mil/greatlakes
 Information 

Recorded monthly mean water levels in this bulletin are results from a representative network of water level gages 

on each lake (see cover map). Providers of these data are U.S. Department of Commerce, NOAA, National Ocean 

Service, and Integrated Science Data Management, Department of Fisheries and Oceans, Canada. Detroit District, 

Corps of Engineers and Environment and Climate Change Canada derive historic and projected lake levels under 

auspices of Coordinating Committee on Great Lakes Basic Hydraulic and Hydrologic Data. 

The Corps makes the bulletin monthly as a public service. The Corps also, on a weekly basis publishes online the 

Great Lakes, Connecting Channels and St. Lawrence River Water Levels and Depths, which supplies a forecast of 

depths in connecting rivers between Great Lakes and International Section of St. Lawrence River. This Monthly 

Bulletin of the Lake Levels for the Great Lakes is available in full color on the internet at 

https://www.lre.usace.army.mil/Missions/GreatLakesInformation.aspx. For questions, email hhpm@usace.army.mil

or call 1-888-694-8313 and select option 1. 

Great Lakes Basin Hydrology

November 2022 

Precipitation in the Lake Superior basin was around 40% average its November average according to preliminary 

estimates. Lakes Michigan-Huron and Erie received significantly below average precipitation and Lake Ontario 

experienced slightly below average precipitation for November. In addition, precipitation over the past 12 months is 

below average for all lake basins. Provisional estimates indicate extremely high November water supplies for Lake 

Superior, while November water supplies were below average for Lakes Michigan-Huron and Erie. Lake Ontario 

water supplies were slightly above average. Also, outflows from Lakes Superior, Michigan-Huron, St. Clair, and Erie 

continued to be above average in November, while the outflow from Lake Ontario into the St. Lawrence River was 

slightly below average for the 2nd consecutive month. 

Lake Superior’s monthly mean water level remained steady from October to November. However, Water levels 

continued with seasonal declines on the other Great Lakes. The decline in levels ranged from less than an inch for 

Lake Ontario to around 4 inches for Lake St. Clair. The latest Great Lakes water levels 6-month forecast predicts 

Lakes Superior, Michigan-Huron, St. Clair, and Erie will decline from November to December. Lake Ontario is 

projected to begin its seasonal rise. 

PRECIPITATION (INCHES)

BASIN 

November 12-Month Comparison 

2022 Average Diff. % of 

Average 

Last 12 

months 

Average Diff. % of 

(1900-2020) (1900-2020) Average 

Superior 3.50 2.48 1.02 141 30.53 30.67 -0.14 100 

Michigan-Huron 1.96 2.80 -0.84 70 29.18 32.99 -3.81 88 

Erie 1.79 2.87 -1.08 62 28.65 35.98 -7.33 80 

Ontario 3.00 3.19 -0.19 94 30.99 36.42 -5.43 85 

Great Lakes 2.47 2.76 -0.29 89 29.67 33.11 -3.44 90 

Lake 

November WATER SUPPLIES1 (cfs) November OUTFLOW2 (cfs)

2022 Average3

(1900-2008) 2022 Average3(1900-2008)

Superior 143,000 17,000 93,000 78,000 

Michigan-Huron -8,000 39,000 209,000 190,000 

Erie -13,000 -3,000 221,000 201,000 

Ontario 22,000 21,000 234,000 238,000 

Notes: Values (excluding averages) are based on preliminary computations; cfs denotes cubic feet per second. 

1 Net basin supply is the net result of precipitation falling on the lake, runoff from precipitation falling on the land which flows to 

the lake, and evaporation from the lake. Negative net basin supply denotes evaporation exceeded runoff and precipitation. 

The net total supply can be found by adding the net basin supply and the outflow from the upstream lake. 

2 Does not include diversions. 

3 Lake Ontario average water supplies and average outflows are based on period of record 1900-2005