Cave River Sink
May 7, 2007
Team: RS Stewart, J Pauel, Rastaman
Notes: RS Stewart
Monday, May 7 was the first day of the St Ann Project (a systematic inventory and assessment of all of the speleological sites in the parish). Five days would be spent investigating the Cave River System, a long network of caves that extends from Aenon Town north to Grants Bailey. It had been chosen as the first work on the project because it is quite challenging, and we prefer to start with the more difficult sites. (It should be mentioned that we've already done a number of sites in St Ann over the years, and many of these will not need to be visited again.)
It was our general intention to work from south (upstream) to north (downstream), so the first order of business was to locate the river sink that is the beginning of the system. When I had dropped by Aenon Town on the Friday before to make arrangements for our stay, a few questions put to several people had immediately supplied information on the general location (reached by a track from the end of a lane to the west), and on the evening before (we arrived Sun, late aft), our hostess, Lisa, had asked a friend of hers, Rastaman, to lead us to it in the morning. At 10:30 AM, we were there.
The sink found here is the dry-season, or normal sink. In times of severe weather, such as Hurricane Ivan in 2004, the flow of the Cave River is too great for the sink to take completely, and the river continues down an otherwise dry riverbed for another 7km (rivercourse length) until it disappears into a number of depressions in a section of pasture land 4.9km to the east (97.4 deg true). During our visit, the entire flow was entering the dry-season sink.
The river in dry-season is actually more of a stream, with a width of about 5-7m, and a depth of about 50cm (you can easily wade upstream in it, without getting your hips wet). At the sink itself, the water is slightly deeper, and flows into low opening/s at the bottom of a cliff. This could not be seen well due to a large accumulation of trash that floated, and sat in piles of bamboo detritus, immediately outside the sink. This included bags, buckets, and large pieces of polyurethane insulation, through which the water flowed as it entered the system. Rastaman informed us that in the past, the sink was cleaned out yearly, with this happening before the rainy-season, but it is a very infrequent event at present. Documentation that will be found in the reports for the caves downstream of the sink will describe the amount of trash that is penetrating the system. It is apparent that the opening to the sink allows trash to pass within. We observed garbage in the water at the entrance in the dry-season. We must note that the input of plastic solid waste is not restricted to the rainy-season and is a year-round phenomenon. Clearing the sink once a year, at most, is not sufficient to keep the waste out of the system.
With the start of the system now located and GPS referenced (two separate positions in agreement, with 7 sat's and WAAS), we pushed on overland to find a second entrance point for the series further to the north. This would allow us to match the KHE maps to surface locations (we needed two points to do this, and the river sink gave us one), which would allow us to find all of the other entrances ourselves.