Lake Waiau

The Lake Waiau is a small alpine lake, which is located below the summit of Mauna Kea in Hawaii.

The Lake Waiau is located at an altitude of 3970 meters within the Pu'u Waiau crater. Its shape is approximately herzförming and it has a maximum diameter of about 100 meters at a maximum water depth of 2 to 3 meters. The lake is fed exclusively by rainfall or melt water while having a catchment area of ​​135,000 m2. The water level of Lake Waiau fluctuates during the year with a maximum water level at the end of snowmelt, which then decreases during the year and in August often is less than one meter. From a water depth of 2.3 meters, the lake has on its west side a drain that empties into the Pohakuloa Gorge. The average surface area of the lake is about 6000 m2, in this case the surface is towards the end of summer usually only a third of the surface at the end of winter.

The bottom of Lake Waiaus situated in the summit area constitutes a specific feature, as it would otherwise only has water permeable soil layers and simple, the water seeps in other places. As a reason for the water-impermeable layer of soil at the site of the lake, the existence of permafrost is contemplated, but was previously detected only at a different point in the summit area. Secured, however, is that there is a least 7.5 meters thick sediment layer on the bottom of the lake.

Since 2010, the Lake Waiau shrink massively and in the fall of 2013, its surface was only 2 % of the normal area. The exact reason for the loss of water is not known. As a possible reason for the thawing of permafrost suspected and the resulting loss of a water-impermeable layer of soil is discussed.

The Lake Waiau also plays a role in the mythology of Hawaiian natives. Besides Poliahu are two more snow goddesses, Lilinoe and Waiau, associated with the Mauna Kea. According to a conjecture of Westervelt, the lake is named after the goddess, as they used it as a bathing place. The summit area of Mauna Kea, including the lake was a sacred site and originally only priests and chiefs accessible. Later occasionally took members of the royal family a trip to the summit area, as the last member visited the Queen Emma in 1881 the summit and took it even a dip in Lake Waiau.