Flash Flood — San Juan, Colorado

2007-07-21 · near Silverton, San Juan, Colorado

Event narrative

Heavy convective rainfall concentrated just north of the La Plata and San Juan County line produced a massive flow of water, rock, and mud which traveled across the Durango to Silverton Narrow Gage Railroad track and dammed up the Animas River about one mile north of Needleton. Initially, the entire river channel was dammed. The river bed at that location was raised 8 feet on the east side of the channel and remained blocked on the west side of the channel. The debris flow covered about 250 feet of railroad track. The peak depth of debris on the railroad track was measured at close to 45 feet. The railroad track did not sustain significant damage, because the lowest several feet of debris on the track consisted primarily of mud. On top of the mud was a lot of rock material with some trees mixed in it.

Wider weather episode

Heavy rainfall concentrated just north of the La Plata and San Juan County line produced a massive flow of water, rock, and mud which flowed across the Durango to Silverton Narrow Gage Railroad tracks and into the Animas River.

View location on OpenStreetMap → (37.6610, -107.6700)

Source: NOAA Storm Events Database, event_id 52040. Narrative written by the NWS forecast office that issued the report.