Fact File: Bay of Fundy ‘tide-millers’ little more than a tall tale

A Facebook post recounting the ahead-of-its-time ingenuity of so-called “tide-millers” in Nova Scotia in the 18th century caught the attention of readers in early September.

The post, which included a striking image of a mill attached to a rock face, claimed wooden water wheels built in narrow inlets were used to harness the extreme tides in the Bay of Fundy to grind grain, saw lumber and power small forges.

However, experts say that while tide mills did exist during the 1700s, they did not operate the way the post describes.

THE CLAIM

“On the coast of Nova Scotia, where the tides of the Bay of Fundy are the highest in the world, a unique community of tide-millers harnessed this raw power for centuries,” read a Sept. 2 Facebook post with more than 1,000 reactions on an account called Old American Life.

“They built sophisticated waterwheels and sluice gates in intricate wooden structures positioned in narrow inlets. As the tide rushed in, it would spin the wheels in one direction; as it rushed out, it would spin them in the other, providing continuous power to grind grain, saw lumber, and even power small forges.”

The post described a “master of the mill” named Angus MacLeod and included a black-and-white photo-like image of a large, wooden water wheel affixed in a narrow inlet to a sheer rock face with water whirling below and what looks like the open bay in the distance.

THE FACTS

Daniel Samson, an associate professor of History at Brock University, said in an interview that while tide mills were used in Nova Scotia at the time, they didn’t operate the way the post describes.

“(The post is) suggesting that they make use of the tidal energy. They don’t,” said Samson, a historian of rural 18th- and 19th-century Nova Scotia who is currently writing a book-length biography of a 19th-century Pictou County, N.S. miller.

Instead, structures would usually be built on small streams with a dammed pond behind the mill, Samson said.

Water would funnel through sluices, or “sea gates,” and fill the pond as the tide came in, and the gates would shut automatically at high water, according to historical non-profit group the Tide Mill Institute in Maine. The mill’s internal gate would control the flow of water from the pond through the water wheel, setting the milling machinery in motion using gravity — not the tides.

Samson says it would be impractical to harness the tides in the way the post describes.

“It would be an incredibly elaborate structure. The gears, the milling, the person having to pay attention to the tides all the time. (It would be) incredibly difficult and an impractical approach to all of this.”

The “raw power” of the bay’s famous, 15-metre tides would also likely be too much for such a structure.

“People have been trying to utilize tidal power in the 20th and 21st centuries now for 75 years or so,” Samson said, referring to projects on the Bay of Fundy. “Every one of those has failed and they’ve been way more structurally sound than a wooden mill.”

While projects like the Cape Sharp Tidal Venture and Pempa’q Tidal Energy Project in the bay have successfully connected to the power grid, they both faced financial and regulatory hurdles that scuttled the projects.

The currents in the bay reach speeds of up to 18 kilometres an hour and have been known to tear blades from turbines, according to the National Research Council Canada.

Unreal history

The Canadian Press could not find any record of an Angus MacLeod running a tide mill in the 1700s.

“There were no doubt dozens of Angus MacLeods, but none that I know of associated with tidal mills, real or imagined,” Samson said in a followup email.

As for the image, photographic cameras did not exist at the time these mills were supposedly used. The details on the image point to it being created using an artificial intelligence tool, and AI-image detector Hive found it to be 87.7 per cent likely to contain AI-generated content.

The account Old American Life is filled with posts using AI-generated images and unsourced historical tales set around the world. The page’s operator, Being Master LLC, has the same name as one that operated a different page that posted AI-generated portraits of Holocaust victims and was denounced this year by the Auschwitz Memorial, according to an investigation by fact-checking site Provereno.

When doing a Google search for “tide millers bay of fundy,” the AI-generated overview appeared to legitimize the false information about historic Nova Scotian tide mills by citing the post in its search result, saying “communities harnessed the rhythmic inflow and outflow of the tides to continuously power water wheels.”

Google search’s AI overview has a disclaimer saying, “AI responses may include mistakes.”

This report by The Canadian Press was first published Sept. 18, 2025.

Colleen Hale-Hodgson, The Canadian Press