Updated 17th October 2004; 7th May 2009; 14th May, 14th October 2011; 30th April 2016; 5th January 2018
A stream sink that takes all of the water (in moderate flow conditions) in one on the main valleys coming down from Alisas. The sink is a small pool against a limestone scar. After a dry period, the pool dries out but there is no sign of any holes, draughting or otherwise, to dig out in the immediate vacinity. Above the sink and on the other side of the road is an old cold store, site 3215, which is being excavated.
Over three days in July 2011, the supposed upstream course of Fuente Aguanaz (or, at least, part of it) was dowsed. The furthest point reached was a small sink close to the entrance of the Sumidero de Cobadal and a complicated set of reactions were found around this sink, 1976. A number of other possible inlets and sinks were also highlighted. See the links below.
Optical brightener was poured into the sink on 27th March 2016 after overnight rain. It was detected at Fuente Aguanaz on the 2nd April giving a throughput time of 4 - 7 days.
Reference: anon., 2004a (February logbook); anon., 2004d (summer
logbook); Corrin, Juan 2006; anon., 2009a (Easter logbook); anon., 2011b (Easter logbook); anon., 2011d (summer logbook); anon., 2016b (Easter logbook)
Entrance pictures: 2004 and 2009 : Injecting optical brightener, Easter 2016
Video: duck in a sink Looking down on the sink with water flowing from left to right : water level check, Easter 2016 (YouTube)
Pete O'Neill in dry sink : wet conditions at Easter 2012 (YouTube)
On area survey: Dowsing reactions close to this cave : All dowsing reactions in the supposed Fuente Aguanaz catchment. (Article about the dowsing carried out in July 2011 can be found here.)