It’s a half-myth that Lake Erie once caught on fire. In 1969, the Cuyahoga River which flows into Lake Erie caught fire due to the high volume of sewage and oily sludge that ended up in the water. People have, over the years, rounded this up and said that Lake Erie itself was on fire. When you consider that Lake Erie covers about 10,000 sq. mi. of surface area, this makes much more sense.