It has come to our attention that residents in some parts of Dominica have recently been noticing an unusually strong smell of sulphur, particularly in the areas of Laudat and Morne Prosper. We have also been informed that the Boiling Lake is emitting unusually strong smells and is currently a murky black colour.
The reasons for these changes in activity are unclear at the present time. However, it is possible that they are related to the unusually hot and dry season that we are currently experiencing in the Caribbean. We believe that these sulphurous smells are NOT related in any way to the swarm of shallow earthquakes that has been occurring over the past two days in the north of Dominica. We are at present investigating the possibility that the black colour of the Boiling Lake reflects the presence of colloidal sulphur.
The Boiling Lake has been known to undergo changes in the past, and its water level has even dropped drastically on occasion. These past incidents appear to have reflected local changes in the geothermal system, and were not related to an increase in volcanic activity. However, in 1901 a small steam and gas explosion from the Boiling Lake (which was almost empty at the time) released harmful gases (probably mainly carbon dioxide) into the atmosphere and killed two people who were at the water’s edge at the time. This incident highlights the potential dangers of the Boiling Lake, especially at times of unusual activity. For this reason, we recommend that people exercise extreme caution when visiting the Lake in its current state. We recommend that:
1) no one climbs down to the water’s edge at this time, and
2) visitors to the Valley of Desolation either avoid approaching the Lake or make their stay at the viewing point above the Lake as short as possible.
Within the next few weeks staff from the Seismic Research Unit will be making a routine visit to Dominica to carry out regular monitoring of the geothermal areas (soufrière). At that time we will be able to release more information about the phenomena discussed here. In the meantime, if anyone notices any further changes in Dominica’s geothermal areas, they should contact the Seismic Research Unit (uwiseismic@uwiseismic.com).
