Earlier this year, the 500-foot-tall San Rafael waterfall in the Ecuadorian Amazon seemed to vanish. The country’s largest waterfall in both height and volume, its disappearance wasn’t caused by a sudden drop in water levels, but instead because the Coca River decided to literally ”drop.” A few meters behind the waterfall, a gigantic hole opened up, changing the riverbed and diverting the river through a nearby arch that survived the collapse.
Exactly why the Coca River suddenly tunneled through its riverbed is a hotly debated topic between geologists and conservationists. An expose in Mongabay on the waterfall’s disappearance quoted Alfredo Carrasco, a geologist and former secretary of Natural Capital at the ministry, as saying that the San Rafael’s location within a volcanic and earthquake-prone region likely played a role. Others, however, point to the existence of the new Coca Codo Sinclair hydroelectric plant, which sits about 20 kilometers upstream of the San Rafael waterfall as a possible culprit. milio Cobo, coordinator of the South America Water Program at the International Union for the Conservation of Nature (IUCN), tells the site that it’s possible the hydroelectric plant may have indirectly caused the waterfall’s demise via a phenomenon called ”hungry waters.”
Cobo believes it’s no coincidence that the riverbed eroded only a few years after the hydroelectric plant opened. ”These are processes that are in scientific papers and there is sufficient evidence that a dam can cause effects of this type on a river,” he added. Officials plan on continue studying the collapse of the San Rafael falls to determine the exact cause, as well as to monitor the near-certain risks for future erosion and increased landslides along the river.
Source: MNN
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