The Unknown Spring, Suwannee River FL

Map and survey by Teddy Garlock

To really emphasize how much I needed a good cave dive, let me recap the days leading up to checking this cave out. A few days before this trip I was out exploring another river cave, Hidden Spring on the Suwannee River. On the way home to the ramp my boat motor lower unit grenaded itself, making lots of crazy noises and rendering it useless. I drifted to the launch and was sad to see chunks of metal come out of the drain plug when I looked into it back at home. I was lucky and found a replacement lower unit for sale about 45 minutes away, so after work the next day I drove out and picked it up, tore my old engine down, put the donor lower unit on and after finishing up late at night, headed to bed.

Donor lower unit partially installed, old lower unit in my cart.

I had plans early the next morning to meet up with friends Brett Hemphill, Derek Dunlop, Steve Lambert and cave diving legend Woody Jasper! I made good time that day, stopping to fuel my boat on the way to the launch. After topping up the boat I needed to fill the van up with fuel, so I did… with GASOLINE! Ethanol free boat gas in fact, adding additional insult to my already expensive mistake. WHOOPS.

Torrential downpour, expensive tow, ruined dive plans, 0/10 recommend.

For those who don’t know, you cannot run gasoline in a diesel engine. If you try, at best you’ll ruin your fuel pump, injectors and honestly the entire engine. At the worst the engine will catch fire and you, your rebreather, your dive gear, your hopes and your dreams will all burn to the ground.

Thankfully I realized my mistake while still pumping (albeit 22 gallons in). I hid my boat in the bushes behind the gas station and took a quick tow back to my house and went about fixing it. I started with a hand pump but quickly decided that was not the way on. Using some big brain thinking (with help from the internet) I decided to disconnect the fuel line near the fuel filter, connect that to a long bit of tubing and then run it into a barrel I recently found in the river. Cycling the ignition about 40 times I was able to use the vehicle’s in-tank fuel pump to pump it all out! Added some diesel, sucked that out, added more diesel and then finished topping it all off at the gas station. All in all I was out $160 for the tow, $75 in tainted useless boat gas and a few hours of my time.

Back in business I reconnected the boat and headed off to the river, hoping to still be able to meet up with my friends. Put the boat in the water, motor started on the first pull, aaannnnnnndddddd no output from the water pump, so either the impeller is bad or the seals are leaking through the system. Damn. I took a chance using a used lower unit without knowing the history or functional status of it, unfortunately the bargain didn’t pan out. Should at least be a simple fix, new water pump and seals and I’m thinking I’ll be back on the water next week

Beautiful KARST
Beautiful KARST

I called up my friends already on the river (it was now about 3pm) but they were tied up with half of them still in the water. Making the most of it, I hiked out to another nearby spring and checked out the impressive sinkhole leading to that cave. Brett called me soon after and said “head to the launch, we’ll pick you up- we have an awesome cave for you to check out!”…

A half hour later I was upriver, gearing up near the shore with THE Woody Jasper watching over.


Map and survey by Teddy Garlock

Until I know the name of the cave I’m just going to call it “The Unknown”. The Unknown is on the northeast shore of the upper Suwannee River with a little fissure entrance and a nice boil at the surface. We didn’t take any measurements but I’d guess it’s solidly a 3rd, maybe even a 2nd magnitude spring. At this point I haven’t even been able to find anything from the Suwannee River Water Management District on it, seems to be pretty unknown. On the day I surveyed the cave the Luraville river guage read 18.25′, and the flow in the cave was at an ideal level so that silt and debris blew out quickly.

Derek and Steve joined me for the dive, starting ahead and doing their best to ensure limited visibility as I made my way through, surveying as I went. The cave is essentially a bedding plane with sand floors and lots of protrusions on the ceiling. There are at least 4 lines in the cave, all disappearing and reappearing at random and sometimes inconvenient spots in the shifting sand. Knowing I was surveying, Steve ran a new line through most of the cave and just connected it to the most consistent existing line as he went. Since this was their second or third dive of the day, Steve and Derek turned early and I continued onward. The cave starts out quite small, requiring frequent turns of your head to squeeze through and make forward progress. Since the floor is coarse sand and the flow is moderate, just grind and go was the way to approach it. About 200′ into the cave it takes on a different appearance, narrowing but getting taller and taking on more interesting morphology. Old beer cans and organic debris litter the floor from the recent flood, or perhaps a surface insurgence yet to be seen.

I surveyed the first 440′ of the cave, it took me about 75 minutes. I’m not the fastest surveyor out there and the cave was pretty tight at times. Coming out was much faster with one little delay- as I was no-vis cruising/smashing along (as you do), I brushed up against a large stick in the sand, my body pulling it out, snagging on me and then snagging my right tank along the way. Quick fix of my tank snoopy loops and I was making progress again.

All in all, a real 12/10 cave to me. I loved the snug passages and sand floors, and the back portion was pretty and enticing. I am excited to return in the near future and finish the survey, maybe adding a little line along the way!

Length surveyed: 440’, allegedly 2000’+. Maximum depth 18’