Great Lakes — Where are They?

In the past, with the exception of examinations specific to Great Lakes’ licenses, USCG “Rules of the Road” questions have not asked for the extended definition of these waters as described in Rule 3(m) Inland. They do now. The mnemonic “HOMES—H(uron), O(ntario), M(ichigan), E(rie), S(uperior)” no longer suffices to answer the questions “What is . . . “ and “What is not . . . “ considered part of the Great Lakes.
systemmap-2

Beyond the Big Five

The Inland Navigation Rules define the “Great Lakes” as “the Great Lakes and their connecting and tributary waters including the Calumet River as far as the Thomas J. O’Brien Lock and Controlling Works (between mile 326 and 327), the Chicago River as far as the east side of the Ashland Avenue Bridge (between mile 321 and 322), and the Saint Lawrence River as far east as the lower exit of the Saint Lambert Lock.”

On parts of the Calumet, Chicago and Saint Lawrence Rivers, in addition to unspecified “connecting and tributary waters,” vessels are required to comply with the behavior and lighting exceptions described in Rules 9, 14 and 23 of the Inland Rules.

The Calumet River

The Calumet River, located in South Chicago, is part of the Calumet River System, which also includes the Grand Calumet, the Little Calumet and the Cal-Sag Channel (short for “Calumet-Saganashkee Channel”). The Inland Rules regard the Calumet River to the narrow, aging and unreliable Thomas J. O’Brien Lock & Controlling Works as part of the Great Lakes. Beyond the O’Brien Lock, the Grand Calumet River becomes part of the Western Rivers System, merging with the Mississippi River in about 300 miles.

The Chicago River

Like the Calumet, the Chicago River is designated by its parts: it has a North Branch and a South Branch (“Bubbly Creek”).  The segment designated as part of the Great Lakes for the Rules of the Road extends from Lake Michigan north to the Ashland Avenue Bridge.  Beyond this point, the river becomes part of the “Western Rivers.”

Saginaw Bay

Saginaw Bay is part of Lake Huron.  It is found between the thumb and the rest of the hand of mitten-shaped Michigan.

The St. Lawrence River as far as . . . 

At the St Lambert Lock, southwest of Montreal, vessels officially exit the Great Lakes.  Locations such as Anticosti Island and Trois-Rivieres, both to the East of St. Lambert in Quebec province, are not part of the Great Lakes System.

Are the Great Lakes Inland Waters of the US?

While US vessels navigating on the Great Lakes follow the Inland Rules of the Road, the Great Lakes are NOT Inland Waters of the United States.  Only Lake Michigan is wholly within the United States.  The other lakes straddle the US-Canadian border.

Exam Questions

(INLAND ONLY) The term "Great Lakes," as defined by the Inland Rules of the Road, includes part of the ________.
A. St. Lawrence River
B. Calumet River
C. Chicago River
D. All of the above
Answer: D

(INLAND ONLY) The term "Great Lakes," as defined by the Inland Rules of the Road, does NOT include _______.
A. portions of the Calumet River
B. portions of the Chicago River
C. Saginaw Bay
D. the St. Lawrence River to Trois-Rivieres.
Answer: D

(INLAND ONLY) For the purpose of the Inland Navigation Rules, the term "Inland Waters" includes which of the following?
A. Any lakes within state boundaries
B. The Great Lakes on the United States side of the boundary.
C. The coastline of the United States out to one mile offshore
D. The waters surrounding any islands of the U.S.
Answer: B

(INLAND ONLY) For the purpose of the Inland Navigation Rules, the term "Inland Waters" includes which of the following?
A. The St. Lawrence River to Anticosti Island
B. The Great Lakes in their entirety
C. U.S. waters out to three miles offshore
D. The Mississippi River System
Answer: D


Scott Balko’s time-lapse video of the Capt. Henry Jackman transiting the Calumet River