On 27 May 1937, a voluminous flood caused the death of at least 300 people in the mining region of Tlalpujahua, Michoacán, central Mexico. The flood was triggered by the breaching of the impoundment of the Los Cedros tailings. The flood reached maximum speeds of ~25 m/s and deposited 1.5 x 10^6 m3 of material. The FLO-2D hydraulic model reproduced the breached flow (0.5 sediment concentration) with a maximum flow discharge of 8000 m3/sec and a total outflow volume of 2.5 x 106 m3.