Lake Waiau

On Mauna Kea, on the island of Hawaii, Lake Waiau is a high-elevation lake that is 3,970 meters (13,020 feet) above sea level. Undoubtedly, it is one of the tallest lakes in the country.

Lake Waiau is the last lake on Hawaii Island and one of very few lakes at all in the state of Hawaii following the disappearance of Ka Wai o Pele in 2018 and the short-lived lake in Halema'uma'u crater in 2020. Its size changes as the water level rise and lowers and is just approximately 100 m across. At times of high water, a little outflow stream can be seen at the northwest end, although it quickly disappears into the ground. Despite being mostly calm, the name in Hawaiian means "swirling water." Even though the water normally freezes over in the winter, aquatic insects like midges and beetles can be seen there reproducing.

There is a trail off Saddle Road that leads to the lake. Although it is not a long hike, some people may find it challenging because the oxygen levels decrease as you ascend the volcano.

Location: Mauna Kea, Hawaii