Shoal Marker Program

TIA places approximately 200  ROCK markers each season from the eastern tip of Howe Island in the Bateau Channel to Brockville in the St. Lawrence River  Canadian waters and supports Save The River (STR)by supplying them with shoal markers.  STR places approximately 100 shoal markers from Cape Vincent to Morristown in the  St. Lawrence River American waters each season.

The primary objective of our shoal marking program is to heighten boater’s awareness of the importance of careful navigation throughout the Thousand Islands region. Our shoal marking program is not intended, nor should it be used for navigational purposes at any time, and boaters should be aware that only a small percentage of shoals are marked each season.

TIA strongly encourages all boaters to use navigation charts when on the river and to be aware that for a variety reasons, shoal markers do break loose from time to time.  As such, previously marked shoals may become unmarked for an extended period of time.  Due to the unpredictability of this occurring,  the Thousand Islands Association disclaims any liability for the absence of any of our shoal markers for any reason.


TIA – Found or Missing Shoal Marker Reporting

TIA shoal markers are white with a distinct orange triangle to indicate a hazard per regulatory standards. These markers have an identification decal indicating property of TIA with reference to the TIA website and email. There is also a QR code that can be scanned using a QR reader app on a smartphone.

From time to time some of these shoal markers break loose and drift away or wash up on shore, and this needs to be reported to TIA. If you find one of our shoal markers in St. Lawrence River  Canadian Waters,  or if you notice a previously marked shoal that is missing a marker, please reach out to us with the location via email at

If you find a shoal marker in St. Lawrence River American Waters, please contact Save the River at (315) 686-2010

Why Your Membership Matters

TIA is the only organization placing shoal markers for the River Community - this is an essential service. Our mission of river safety is to heighten boater’s awareness of some dangerous shoals to avoid . TIA strongly encourages all boaters to use navigation charts when navigating the St. Lawrence River. Please be a TIA supporter, we rely on membership dues & donations to be sustainable.

Connect with TIA on social media and be part of our river community.