As the U.S. dives headfirst into its St. Patrick's Day festivities, drunk Americans often don't realize the damage left in their wake—or how much they get wrong about celebrating the Irish holiday. These seven facts about St. Patrick's Day should sober up any American who puts back a few too many rounds of Guinness, but they probably won't. You guys are monsters.

1. The original reason they started making the Chicago River green was to detect human waste and sewage.

"Don't think about it, just paddle."
"Don't think about it, just paddle."

Chicago first began dyeing the river green to detect illegal sewage polluting the river, according to CBS Chicago. If toxic sludge was detected, the waterway would turn a beautiful shade of emerald around the buildings oozing the most waste. Conservationist groups estimate that "1.2 billion gallons of partially treated human and industrial" waste still flows into the Chicago river each day. Now they just die it green for fun.

Sources: CBS Chicago | American Rivers | Irish Central | WalletHub | Backtrack | Oddee | CNN