Karst Underwater Research has been exploring the Weeki Wachee and Twin Dees cave systems since 1996. Both springs are on State Park property and require a permit to dive them. The main Weeki Wachee Spring is well known as a tourist attraction for the underwater mermaid shows held there daily, but until 2007 no significant exploration of the cave system had taken place due to the very high flow present in the entrance fissure. During 3 separate periods of low aquifer water levels in 2007, 2009 and 2012 a significant amount of underwater cave passage was explored to a maximum depth of 407 ffw. On the same property lies Twin Dees Spring (Little Spring), initially explored by Paul Heinerth and Sheck Exley in the 1970s and 80s. In 1996 Jeff Petersen and Dave Miner of KUR discovered an enormous underground room and deep spring tunnel at 300 ffw which they named Middle Earth and the Alph Tunnel respectively. Further exploration of this system did not occur until 2011, when Brett Hemphill and Andrew Pitkin extended the Alph Tunnel to the southeast in the direction of Weeki Wachee. Continued effort over the next 3 years resulted in a large amount of new passage being explored, almost all of it deeper than 300 ffw, and the eventual connection of the two systems on September 13th, 2014.

For additional information please see the reports below.