sentences:  Because the San Pedro River was blocked, the water level of Riñihue Lake started to rise quickly.Each meter the water level rose was equivalent to 20 million cubic meters, which meant that 4.8 cubic kilometers of water would release into the San Pedro River (easily overpowering its flow capacity of 400 cubic meters per second) if it rose above the first, 26-meter-high dam.This potential disaster would have destroyed all the settlements along the course of the river in less than five hours, and had more dire consequences if the dam suddenly broke.