Bill and I dove in Island Springs. It’s in the middle of the river, just upstream from Katie’s Landing off SR 46. Russ Moncrief again provided us with the generous loan of his boat, powered by a “go-devil” motor–which is sort of a Cuisinart at the end of a long metal rod. Its tricky to operate but is great for shallow and weed-choked waters, and certainly came in handy here. It worked great, and Bill is now learning to turn on the key *before* pulling the starter rope a dozen times. But I can’t complain as he got us over the spring, threw in a floating dive flag, and then both of us suited up and got in the water. We had visited the spring once before and knew enough to anchor downstream, least the algae-laden silt around the limestone ruin the viz.
Underwater, we sank down to the basin of the spring, which drops from about three feet in the river bottom to about l5 feet. From here, we dodged a sunken tree trunk and entered the cave mouth. The mouth slopes downward gradually, then just out of the range of light, it plummets sharply down into the rock. We followed it into the narrow tunnel, for as far as we could, feeling the strong upwelling of the 4.5 million-gallon a day springs. Bill had read a hydrologist’s report that said water coming out of Island Spring was actually “connate [prehistoric] sea water” originating from somewhere deep in the aquifer. The chloride content was so high a wavy “halocline” layer was created where the upwelling spring water met the fresher water of the river. Very surreal.
Back at Katie’s, we stopped to chat with Russ and Katie, who are some of the nicest folks you’d want to meet. Katie insists Island Spring is actually called “Sulfur Spring,” as it has a sulfur scent and a cave-diving team from UF once mapped it as such. But since we were likely suffering from nitrogen overload, we decided to call it Island Spring, even though in his right mind, Bill knows it is not wise to argue with someone who has a Landing named after them.