The first recorded European sighting of the lake was in 1870 by Edmund Watt and Henry Alfred Alford Nicholls, two Englishmen working in Dominica at that time.[1] In 1875, Henry Prestoe, a government botanist, and Nicholls were commissioned to investigate this natural phenomenon. They measured the water temperature and found it to range from 180 to 197 °F (82–92 °C) along the edges, but could not measure the temperature at the centre where the lake is actively boiling. They recorded the depth to be greater than 195 feet (59 m).

Periodically, there have been fluctuations in the level and activity of the lake. In the 1870s it was deep; after a phreatic eruption nearby in 1880, the lake disappeared and formed a fountain of hot water and steam. Another phreatic eruption lowered the lake level by some 33 feet (10 m) from December 2004 to April 2005; later the lake level rose again, refilling the lake in just one day.[2] The rapid draining and refilling of the lake implies that it is suspended well above the local water table and that a continuous flux of steam or gas generated by an underlying magmatic intrusion drives water up into the lake.[2] A disturbance to the supply of gas can cause the lake to drain through the porous connection that normally allows steam to rise and heat the lake.[3]