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Current Connecting Channel Conditions

Click here for a graphic showing the profile of the Connecting Channels. Near real time water levels in the Channels can also be accessed from the graphic by clicking on the number associated with your location of interest.

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We do not have the ability to offer email updates at this time. The Connecting Channels Forecast is updated each week on Thursday afternoon or Friday morning.

Connecting Channels Forecast

GREAT LAKES, CONNECTING CHANNELS AND ST. LAWRENCE RIVER
WATER LEVELS AND DEPTHS
Expected water levels on the Great Lakes, Connecting Channels and the St. Lawrence River are given in inches above (+,0) or below (-,0) Low-Water Datum (LWD,0). LWD is a plane of reference on a navigation chart, also known as Chart Datum. LWD elevations shown below are given in International Great Lakes Datum, 1985 (IGLD 1985,0).
Forecast Point Low Water Datum (ft) Expected Levels (inches above or below Low Water Datum,0)
Current Week 1 Week 2 Week 3 Week 4
IGLD 1985 22-Mar 29-Mar 5-Apr 12-Apr 19-Apr
GREAT LAKES
Lake Ontario   243.3 23 25 26 28 30
Lake Erie   569.2 36 37 38 38 39
Lake St. Clair   572.3 30 31 32 32 33
Lake Michigan-Huron   577.5 15 15 16 16 17
Lake Superior   601.1 0 1 1 1 1
ST. LAWRENCE RIVER
Above Long Sault Dam 0 237.9 24 27 30 31 33
Above Iroquois Dam 1 240.3 17 19 22 23 25
Ogdensburg 2 242.4 22 24 26 28 31
Alexandria Bay 2.1 243 22 24 25 27 29
Head of river at Cape Vincent 3 243.3 23 25 26 28 30
DETROIT RIVER
Lake Erie at Pelee Passage 4 569.2 36 37 38 38 39
Mouth of River at Gibraltar 5 569.5 36 37 38 38 39
Fort Wayne 5.1 571.1 35 36 36 37 38
Head of River above Belle Isle 6 572 32 32 33 34 34
ST. CLAIR RIVER
Mouth of River at St. Clair Flats 7 572.3 30 31 32 32 33
Algonac 8 572.8 32 33 34 34 35
St. Clair 9 574.4 25 25 26 26 27
Blue Water Bridge 10 576.2 22 23 23 24 24
Head of River at Fort Gratiot 11 577.2 22 23 23 24 24
Lake Huron Approach Channel 12 577.5 15 15 16 16 17
ST. MARYS RIVER
Mouth of River at Detour 13 577.5 15 15 16 16 17
West and Middle Neebish 14 577.8 11 11 12 12 13
Head of Little Rapids 15 578.4 6 7 7 8 8
U.S. Slip 16 578.7 7 7 8 9 9
Above Locks 17 600.4 3 3 3 3 4
Head of River at Point Iroquois 18 601.1 0 1 1 1 1
UNDERSTANDING THE FORECAST
Available water depth is determined for a location by adding (if+) or subtracting (if-) the amount from the above table to the appropriate channel depth shown in the profile Connecting Channel Depths Graphic or to water depths shown on National Oceanic and Atmospheric Administration (NOAA) navigational charts.
               
CAUTION
Depths so determined are representative of a still water surface elevation, disturbed by neither wind nor other causes. Depths, however, may be reduced or increased as much as several feet for short periods due to these disturbances, or when sections of channels develop shoals. Vessel masters should refer to "Local Notice to Mariners" for extent of shoaling and scattered bedrock projections in all channels.
FOR FURTHER INFORMATION CONTACT: FOR MORE INFORMATION VISIT: WATER LEVEL INFORMATION SUPPLIED BY:
Detroit District Corps of Engineers Detroit District Great Lakes Homepage NOAA, National Ocean Service
477 Michigan Avenue International Joint Commission SSMC4, STATION 7523
Detroit MI, 48226 Great Lakes Information Network 1305 East-West Hwy
1-888-694-8318 ex. 1 NOAA, Tides and Currents Silver Spring, MD 20910-3233
email: hhpm@usace.army.mil U.S. Coast Guard - District 9 (301) 713-2902

Detroit District Disclaimer

NOTICE: All data contained herein is preliminary in nature and therefore subject to change. The data is for general information purposes ONLY and SHALL NOT be used in technical applications such as, but not limited to, studies or designs. All critical data should be obtained from and verified by the United States Army Corps of Engineers, Detroit District, Engineering and Construction Division, Hydraulics and Hydrology Branch, 477 Michigan Ave., Detroit, MI 48226. The United States of America assumes no liability for the completeness or accuracy of the data contained herein and any use of such data inconsistent with this disclaimer shall be solely at the risk of the user.

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