According to the U.S. Geological Survey Hawaiian Volcano Observatory the newly-formed lake inside Kilauea volcano is almost 130 feet deep, 880 feet long and 430 feet wide. The temperature of the water at the surface is now between 160 and 180 F, with temperatures beneath potentially higher. This makes the lake one of the world's hottest bodies of water. Scientists are using thermal cameras to monitor temperatures.
The water in the volcano's belly began to form a lake after the volcano erupted in 2018. In July 2019, helicopter pilots began to notice water pooling in the lowest part of the crater. Since then, water levels have risen steadily. Today, the lake has an area larger than five combined football fields. The water color is rust brown due to chemical reactions.
In May 2018, lava poured from fissures to the east, the lake swiftly drained and part of the caldera floor collapsed. This lowered the base of the volcano to the level of the water table. Don Swanson, at the U.S. Geological Survey’s Hawaiian Volcano Observatory explains, “We know that the crater floor dropped a little more than 70 meters below the water table in 2018. Any time that you punch a hole below the level of the water table, water is eventually going to come in and fill that hole.”
Kilauea has an explosive history. Now scientists are concerned about the possible effects of the water coming into contact with the magma. The magma could rise up the conduit and intersect with the lake, causing a steam explosion. Or the crater floor could collapse and the water drop to a zone where it would become steam. Either scenario is likely to produce a steam explosion.