A graphic showing the profile of the Connecting Channels can be viewed by clicking "Current Conditions" below.
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. Current Conditions
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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
Expected
Levels (inches above or below Low Water Datum,0)
Current
Week 1
Week 2
Week 3
Week 4
IGLD 1985
3-Feb-12
10-Feb-12
17-Feb-12
24-Feb-12
2-Mar-12
GREAT LAKES
Lake
Ontario
243.3
32
32
32
32
33
Lake Erie
569.2
36
36
36
37
37
Lake St.
Clair
572.3
23
23
23
23
24
Lake
Michigan-Huron
577.5
-2
-2
-2
-2
-2
Lake
Superior
601.1
-9
-10
-10
-11
-12
ST. LAWRENCE RIVER
Above Long
Sault Dam
0
237.9
58
55
47
47
38
Above
Iroquois Dam
1
240.3
44
41
35
35
29
Ogdensburg
2
242.4
41
40
37
37
35
Alexandria
Bay
2.1
243.0
33
33
32
32
31
Head of
river at Cape Vincent
3
243.3
32
32
32
32
33
DETROIT RIVER
Lake Erie
at Pelee Passage
4
569.2
36
36
36
37
37
Mouth of
River at Gibraltar
5
569.5
35
35
35
34
34
Head of
River above Belle Isle
6
572.0
23
23
23
23
24
ST. CLAIR RIVER
Mouth of
River at St. Clair Flats
7
572.3
23
23
23
23
23
Algonac
8
572.8
22
22
22
22
22
St. Clair
9
574.4
15
15
15
15
15
Blue Water
Bridge
10
576.2
8
8
8
8
8
Head of
River at Fort Gratiot
11
577.2
1
1
1
1
1
Lake Huron
Approach Channel
12
577.5
-2
-2
-2
-2
-2
ST. MARYS RIVER
Mouth of
River at Detour
13
577.5
-2
-2
-2
-2
-2
West and
Middle Neebish
14
577.8
-3
-3
-3
-3
-3
Head of
Little Rapids
15
578.4
-4
-4
-4
-4
-4
U.S. Slip
16
578.7
-5
-5
-5
-5
-5
Above
Locks
17
600.4
-7
-8
-9
-9
-10
Head of
River at Point Iroquois
18
601.1
-9
-10
-10
-11
-12
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.
