View of Rat Creek debris flow from above
The atmospheric river, a narrow, powerful track of water vapor that can deliver tremendous volumes of rain, hit the central California coast and stalled there between January 26 and 28, 2021 — with catastrophic consequences. The area around Rat Creek, about 20 miles south of Big Sur's town center, received more than 8 inches of rain during a 2-day period, according to the National Weather Service. Rainwater washed dead trees, ash, mud, and rock downslope from the nearby watershed, scorched by the Dolan Fire in Los Padres National Forest in the fall of 2020. Drain pipes that run below Highway 1 were rapidly clogged with the debris and were eventually overwhelmed. The roadway was no match for the overflowing culverts, resulting in a massive collapse of the rocky cliff. On January 29th, a USGS reconnaissance flight snapped this dramatic photo above the Rat Creek drainage showing the debris flow.