A Cold and Amost Dry Boiling Lake

 

Today 28th December 2004 - the first working day for Public Servants, merchants and other private sector entities after the extended lake Christmas & Boxing Day "weekend", starting at about 9:00 a.m., four Forestry & Parks (Bertie, Randy, Stephen-T and Mr. James), as well as a camera man from Marpin TV, made the journey to the Boiling Lake to verify the information that had been relayed to the Forest Officer/National Parks on Christmas Day, that the Boiling Lake was "no more".

 

Based on what was seen, it appears that Dominica will not be able to boast of having the world's largest boiling lake - at least not for a while (and for how long, is anybody's guess).

 

On their way towards the long, steep flight of steps coming into the Breakfast River Valley, we got whiffs of sulphurous gas, and thought that this was an OK sign. Jaco Parrots also made the presence in the area known, with a few sets of vocalizations. They we arrived at the summit of Morne Nicholls - the highest point along the trail - they reportedly looked towards the east, in the direction of the Boiling Lake's crater. The usual thick cloud of white vapour that would indicate the location of the Boiling Lake was absent, and the other clouds of vapour that are usually emanating from fumaroles on the slopes to the west of the Boiling Lake were also very quiet!

 

Trekking down into the Valley of Desolation, they were greeted by the familiar sight of clouds of steam belching out from the large fumaroles. The pot of thick grey-blue mud that had opened up in 2003, near the site of the 1997 phreatic eruption / explosion, was boiling away violently, but the liquid in the "pot" was not as thick as when they (Arlington) last saw it in 2003.

 

When they emerged at the edge of the valley that forms the "final" section of the Valley of Desolation, i.e. when one is just less than 10 minutes from the lake, they observed that there was very little fumarolic activity in that section of the Valley.

 

Upon arrival at lakeside (at about noon), the following observations were made:

 

1.    Water Level: The level of the water in Boiling Lake was extremely low, and was lower than what was seen when the lake had gone into  similar phase back on Sunday 17th April 1988.  The lake was not "bone dry", but the pool of water that remained was just about 40ft wide (by estimate). Under normal conditions, the lake would be about 200ft across.

 

From their estimation, the lake level has dropped possibly between 30 and 40ft. This is based upon Forestry's current observations, compared with the measurements that we made in 1988, when the lake had dropped some 29ft then.  The lake outlet was well above the water

 

2.    Water Colour: The water had assumed a dark grey colour, similar to what was seen last year April (when the smell of sulphurous gases was pervading the atmosphere in the Roseau Valley and beyond for more than a month last year), and similar to what was seen in the lake on Tuesday 19th April 1988.

 

3.    Conditions of Lake Surface: there was no visibility of any vapour rising from the surface of the water in the lake. There was no vigorous boiling as is customary, or any bubbling - as such -  save for one lone spot on the eastern edge of the lake where gas was coming to the surface  was reported.  The water surface was generally calm, and the officers reported that on it the reflection of part of the lake's crater rimmed by Clusia trees to the east. 

 

Also, they did not feel any warm air coming from the lake basin.

 

4.    General Lake Conditions: (a) The sulphurous ring indicating the lake's normal high water mark was very evident. There was also a very thick layer of grey mud beginning from some 20ft below the normal high water mark . The mud has started to crack after the 3-4 days of sun, revealing cream-coloured sand underneath a layer of possibly more than 6" of mud.

 

(b) Some of the areas on the mud were showing some level of discoloration: i.e. reddish-brown, mustard and yellow. 

 

(c) There was also a darker ring on the mud (estim. at about 1ft wide), just a few inches above the water surface.

 

(d) The two streams had cut paths across the mud.

 

(e) Some layering (like a layered cake) was also observed on the eastern side of lake, above the water.  These layers appear to be almost the same width/height, about a couple of inches high. This would probably indicate that the water dried up in stages, but also very quickly too.

 

(f) Compared to April 1988, there was considerably more rubble in the lake, near where the ravine enters the lake. Some of this new material, I reckon, was brought in last year, when several landslides occurred in the watershed of the ravine that feeds the lake and the rubble was brought into the lake, even creating a small beach.

 

5.    Inflow Into the Lake: The two sources of surface water feeding the lake, i.e. the very acidic ravine and the mini-waterfall, were both flowing at near normal strength at the time the officers arrived, and when they left at 1:00 pm.

 

Earlier this morning, Seismic Research Unit (SRU) had requested that if possible, whether a water sample and a temperature reading could be taken from the lake. On assessing the conditions, and knowing what the officers know now about how the lake is able to behave when it is in this condition, they felt it would have been much to risky going down to, or even getting close to the water's edge.  

 

These basically are were observations made. Some video footage and some digital shots were taken, and an interview to Marpin on location at lakeside was done.

 

The Division is very optimistic that the lake will return to its "normal" conditions. It put on similar displays in April-May 1988, April 1971, January 1901, and December 1900 - when it claimed the lives of two persons.  The big question is WHEN?  In 1988, it certainly took more than a month to refill completely, though it appears to have done so in stages.

 

Where does the water go to, and so suddenly, and being able to return so rapidly at that? Is it that the hot-gas vent got clogged? But where would all that water disappear to? Any explanation, SRU?

 

A Press Release will be sent out by Forestry & Parks, particularly to the tourism service providers (tour operators, hotels, tour guide companies) about the dangers associated with the Boiling Lake when it is in such "unpredictable" conditions, and warning visitors to the lake (locals and foreigners) about not hanging around the lake in its present.

 

 

Eric Hypolite

Director of Forestry, Wildlife and Parks