San Rafael Falls

The San Rafael Falls (Spanish: La Cascada San Rafael) were, until 2 February 2020, the tallest falls in Ecuador. The 130-metre (430 ft) falls were located on the Coca River in Cayambe Coca Ecological Reserve until a collapse of the river bed upstream of the falls diverted the river underneath the band of hard rock that had originally formed the lip of the waterfall,[2] connecting to a cave below and creating a new natural bridge, possibly surpassing Xianren Bridge as the longest in the world.[3] The natural bridge subsequently collapsed in February 2021.[4] The falls were a significant tourist attraction with a recorded 30,000 visitors during 2019.[5]

San Rafael Falls
Location	Sucumbíos and Napo, Ecuador
Coordinates	0°06′13″S 77°34′53″W
Type	Tiered plunges (until 2015) Plunge (2015–2020)
Total height	131 m (430 ft) (until 2020)[1]
Number of drops	2 (until 2015) 1 (2015–2020)
Total width	30 m (98 ft) (until 2020)[1]
Average width	23 m (75 ft) (until 2020)[1]
Run	46 m (151 ft) (until 2020)[1]
Watercourse	Coca River
Average flow rate	400 m3/s (14,000 cu ft/s) [1]

There has been discussion as to whether the riverbed collapse and subsequent disappearance of the falls is connected with the operation of the Coca Codo Sinclair Dam some 20 km upstream. There are concerns too about how the altered hydrology of the river may affect its ecology.[2] Additionally, the river effectively bypassed the resistant rock of the brink of the falls, causing a sudden river rejuvenation, which in turn has resulted in very rapid headward erosion of a steep-sided gorge upstream of the sinkhole, threatening numerous structures upstream, including the Coca Codo Sinclair Dam.[6]