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Geography · Trade · Chart

Lake Ontario is 55% Canadian water — Trump just renamed it “Lake America”

On August 27, 2026, President Trump signed an executive order renaming Lake Ontario to “Lake America” inside the United States, escalating the trade war with Canada. Splitting each Great Lake along the International Boundary Commission's own surveyed treaty line shows Ontario is majority-Canadian by surface area — and Canada holds more than a third of all five lakes combined.

Published 27 Aug 2026 · Open Data Canada Sources International Boundary Commission · Natural Earth · CNN, USA Today, CNBC, Politico, The Guardian, AP
Map of the five Great Lakes shaded by country: Superior 35.8% Canadian, Michigan 0% Canadian (entirely US), Huron 61.0% Canadian, Erie 50.5% Canadian, Ontario 54.7% Canadian, with a stamp marking Ontario as renamed Lake America

What the chart shows

Each lake's polygon was cut along the actual surveyed Canada–U.S. boundary — the International Boundary Commission's official digital boundary (shapefile v1.3, built from NAD83 survey monuments and shore turning points dating to 1817–1820) — not a generalized country outline. The pieces were then assigned to Canada or the U.S. and summed in EPSG:3174 (NAD83 / Great Lakes & St. Lawrence Albers), an equal-area projection.

Lake Total km² Canada km² U.S. km² Canada share
Superior 82,311 29,460 52,851 35.8%
Michigan 57,541 0 57,541 0.0%
Huron 59,937 36,550 23,387 61.0%
Erie 25,736 13,002 12,734 50.5%
Ontario 19,464 10,653 8,810 54.7%
All five lakes 244,987 89,664 155,323 36.6%

Lake Michigan is the only Great Lake entirely inside the United States — it never touches the border. Lake Ontario, the one Trump's order renamed, is the one lake where Canada holds a clear majority of the surface area.

Lake Erie is effectively a coin flip. This method puts it at 50.5% Canadian; a coarser cross-check using generalized country polygons instead of the surveyed line puts it at 49.6%. The two methods agree to within about a percentage point on every lake, Erie included — but Erie's boundary runs so close to the lake's geographic center that this small a gap is enough to flip which country holds the nominal majority. Treat Erie as roughly even, not a confirmed edge either way.

What actually happened

Trump signed the order Thursday afternoon in the Oval Office, effective “immediately,” following through on a threat made on social media earlier in the week. It follows the collapse of U.S.–Canada trade negotiations and is widely covered as an escalation — reported by CNN, USA Today, CNBC, Politico, The Guardian, and the AP.

The order only changes the name as used within the United States. Canada has given no indication it will adopt “Lake America” — and by this analysis, Canada holds the larger share of the lake's surface anyway.

Sources

Method Each lake polygon cut along the IBC surveyed line and measured with GeoPandas/Shapely in EPSG:3174. Cross-checked against a second method (country-polygon intersection using Natural Earth admin-0 boundaries), which agrees within about 1 percentage point on every lake except Erie's majority side.