The Waterway
Only three navigational charts covering the area
between Michipicoten Island and Whitefish Bay are available.
These navigational charts
include:
a. Lake Survey Chart No. 9, "Lake Superior," which shows all of Lake Superior at a scale of 1:600,000 published by the U.S. National Oceanic and Atmospheric Administration (NOAA).
b. Canadian Chart 2310, "Lake Superior, Caribou Island to Michipicoten Island," which shows the area from slightly north of Michipicoten Island to slightly south of Caribou Island at a scale of 1:97,280 is published by the Canadian Hydrographic Service.
c. Lake Survey Chart No. 92, "Lake Superior, St. Mary’s River to Au Sable Point," which shows the southeastern portion of Lake Superior from Sault Ste. Marie to just south of Caribou Island and west to Au Sable Point Light at a scale of 1:120,000 also is published by NOAA.
Great Lakes mariners normally use NOAA Lake Survey Chart No. 9 for navigation on Lake Superior. Larger scale charts are available for smaller areas, including harbors, where more detail is required. Lake Survey Chart No. 9 contains the following note: "Owing to the small scale, many aids to navigation, depths, contours, and topographical features have been omitted. For details, consult Coast and Harbor charts."
Lake Survey Chart No. 9 shows bottom contours of less than 3 fathoms and less than 5 fathoms around Caribou Island by blue shading in two tones. Two locations of charted depths of 6 fathoms are shown northeast and northwest of the shaded areas. The extent of shoaling with depths in excess of 5 fathoms but less than 10 fathoms is not shown and the mariner is not made aware of the extent of the shoal area north of Caribou Island known as North Bank, as identified on Canadian Chart 2310.
After this accident, the Coast Guard requested the Canadian Hydrographic Service to conduct a hydrographic survey of the area north of Caribou Island to confirm the charted soundings and to update the charted data. Current charts are based on a survey conducted by the Canadian Hydrographic Service in 1916 and 1919.
The Canadian Hydrographic Service conducted a survey from May 19 to July 8, 1976, and from August 7 to September 30, 1976. The survey included the waters between Michipicoten Island and Caribou Island bounded by latitudes 47 l0' N and 47 04 5? N and longitudes 85 33 W and 86 11 W. Soundings were obtained by echo soundings and geographic positions were determined by use of a special three-station mini fix system.
The results of the survey were reduced to a datum of 182.99 meters (599.85 feet) above the International Great Lakes Datum. This base datum is within 0.53 foot of the datum used on current charts.
The hydrographic survey conducted by the Canadian Hydrographic Service of the area north of Caribou Island produced bottom contours very close to those shown on Canadian Chart 2310. In some locations on North Bank, some soundings were less than charted depths; however, in all instances these locations are within the 10-fathom curve as shown on Chart 2310. No soundings less than 10 fathoms were indicated either north or east of the charted 10-fathom curve.
Columbia Transportation Division, the operator of the FITZGERALD, conducted an independent hydrographic survey of the shoal area north of Caribou Island. Water depths were determined by sonic devices, lead line, and direct measurement by divers. The results of this survey show water depths that vary slightly from the Canadian survey. These differences can be attributed to the rocks and boulders on the bottom and the various tracklines on which soundings were recorded.
A former chief mate of the FITZGERALD testified that between September 13 and October 3, 1975, the FITZGERALD discharged at Toledo, Ohio. Because of the FITZGERALD’s deep draft, she was not able to pull up to the dock and had to lay off some 12 feet each time. The ship seemed to plow its way toward the dock every trip, he said. Similar "groundings" of other Great Lakes bulk cargo vessels during discharge at various ports were observed by Coast Guard Marine Inspectors during the winter of 1976 and the spring of 1977 and by Safety Board personnel during the summer of 1977.
a. Lake Survey Chart No. 9, "Lake Superior," which shows all of Lake Superior at a scale of 1:600,000 published by the U.S. National Oceanic and Atmospheric Administration (NOAA).
b. Canadian Chart 2310, "Lake Superior, Caribou Island to Michipicoten Island," which shows the area from slightly north of Michipicoten Island to slightly south of Caribou Island at a scale of 1:97,280 is published by the Canadian Hydrographic Service.
c. Lake Survey Chart No. 92, "Lake Superior, St. Mary’s River to Au Sable Point," which shows the southeastern portion of Lake Superior from Sault Ste. Marie to just south of Caribou Island and west to Au Sable Point Light at a scale of 1:120,000 also is published by NOAA.
Great Lakes mariners normally use NOAA Lake Survey Chart No. 9 for navigation on Lake Superior. Larger scale charts are available for smaller areas, including harbors, where more detail is required. Lake Survey Chart No. 9 contains the following note: "Owing to the small scale, many aids to navigation, depths, contours, and topographical features have been omitted. For details, consult Coast and Harbor charts."
Lake Survey Chart No. 9 shows bottom contours of less than 3 fathoms and less than 5 fathoms around Caribou Island by blue shading in two tones. Two locations of charted depths of 6 fathoms are shown northeast and northwest of the shaded areas. The extent of shoaling with depths in excess of 5 fathoms but less than 10 fathoms is not shown and the mariner is not made aware of the extent of the shoal area north of Caribou Island known as North Bank, as identified on Canadian Chart 2310.
After this accident, the Coast Guard requested the Canadian Hydrographic Service to conduct a hydrographic survey of the area north of Caribou Island to confirm the charted soundings and to update the charted data. Current charts are based on a survey conducted by the Canadian Hydrographic Service in 1916 and 1919.
The Canadian Hydrographic Service conducted a survey from May 19 to July 8, 1976, and from August 7 to September 30, 1976. The survey included the waters between Michipicoten Island and Caribou Island bounded by latitudes 47 l0' N and 47 04 5? N and longitudes 85 33 W and 86 11 W. Soundings were obtained by echo soundings and geographic positions were determined by use of a special three-station mini fix system.
The results of the survey were reduced to a datum of 182.99 meters (599.85 feet) above the International Great Lakes Datum. This base datum is within 0.53 foot of the datum used on current charts.
The hydrographic survey conducted by the Canadian Hydrographic Service of the area north of Caribou Island produced bottom contours very close to those shown on Canadian Chart 2310. In some locations on North Bank, some soundings were less than charted depths; however, in all instances these locations are within the 10-fathom curve as shown on Chart 2310. No soundings less than 10 fathoms were indicated either north or east of the charted 10-fathom curve.
Columbia Transportation Division, the operator of the FITZGERALD, conducted an independent hydrographic survey of the shoal area north of Caribou Island. Water depths were determined by sonic devices, lead line, and direct measurement by divers. The results of this survey show water depths that vary slightly from the Canadian survey. These differences can be attributed to the rocks and boulders on the bottom and the various tracklines on which soundings were recorded.
A former chief mate of the FITZGERALD testified that between September 13 and October 3, 1975, the FITZGERALD discharged at Toledo, Ohio. Because of the FITZGERALD’s deep draft, she was not able to pull up to the dock and had to lay off some 12 feet each time. The ship seemed to plow its way toward the dock every trip, he said. Similar "groundings" of other Great Lakes bulk cargo vessels during discharge at various ports were observed by Coast Guard Marine Inspectors during the winter of 1976 and the spring of 1977 and by Safety Board personnel during the summer of 1977.
Posted: Sat - December 11, 2004 at 09:56 PM
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Published On: Dec 11, 2004 09:57 PM
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Published On: Dec 11, 2004 09:57 PM