This accident occurred on October 17, 1814 when ruptured vats at the Meux and Company Brewery caused some "323,000 imperial gallons (1,470 m3) of beer" to burst into the streets of London.
The wave of beer destroyed two homes and crumbled the wall of the Tavistock Arms Pub, trapping the barmaid under the rubble.
The brewery was located among the poor houses and tenements of the St Giles Rookery; where whole families lived in basement rooms that quickly filled with beer. The wave left nine people dead: eight due to drowning and one from alcohol poisoning.
I can't believe this wasn't in my AP European History curriculum.
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