denise
01-31-2010, 11:06 AM
Dayo instructors and students were around this week in cave country to witness the spectacular flooding of many of the caves in the area. We were diving in cave country just this last week with Joe (pics here (http://www.divetraining.net/pictures/2010_jan_19/)), and we had some beautiful dives in Peacock on Monday 18th Jan, where we had near perfect visibility. We also dived in Little River on Tuesday 19th January, and although the basin was a bit higher than normal, tannic and cold, the cavern and cave was in good condition. The flow throughout was extremely low, and we had visibility of ~ 50 feet.
This week was an entirely different matter. We headed to cave country with a bunch of divers: Lou, Brent and Cam for Intro Cave Course (http://www.scubadiver.cc/forums/showthread.php?t=1392); Matt, David and Frank for Full Cave (http://www.scubadiver.cc/forums/showthread.php?t=1388), and Jim (with Scott swimming along) for Sidemount Cave (http://www.scubadiver.cc/forums/showthread.php?t=1379), all eager to do some cave diving.
On Sunday we visited Cow Springs and Little River Springs, and at both the spring heads were 5-10 feet higher than the previous week, and the systems undiveable, due to an intrusion of tannic water.
Little River on Tuesday 19th Jan:
http://www.divetraining.net/pictures/2010_jan_19/DSC05129.jpg
Little River less than a week later:
http://www.divetraining.net/pictures/2010_jan_28/DSC05194.jpg
Water level is 10+ feet higher, there is a visible boil on the surface, and the cave is siphoning strongly with nasty cold river water.
On Monday we visited Peacock, and noticed water pouring in across the slough into P3. It was siphoning strongly, and the basin filling up fast.
http://www.divetraining.net/pictures/2010_jan_28/p3_monday2010.jpg
River water entering the run and basin of P3
We headed across the park to Orange Grove, where we had a very nice dive, visibility was 40 or so feet. That afternoon we moved to Peacock 1, but the tannic water had already made its way through Mainline, and through the majority of the Peanut Tunnel. The visibility in the system ranged from 1 foot to 10 feet, and the temperature was mid fifties.
We dived at Ginnie Springs for the remainder of the week, and conditions there were very good. Flow was the usual (quite strong!), and visibility in the cave was 60+ feet. The eye was a bit green looking, but cleared as you go through the cavern, but the river spilled over in the ear, and visibility there was close to zero. It was also very cold (50 something degrees :()
On Wednesday evening TJ and I tried out the new Hollis H-160 DPV / Underwater Scooter. She rides very smooth, and is very easy to manage and VERY fast.
Click here for more information on the Hollis H-160 DPV / Underwater Scooter (http://www.scubadiver.cc/forums/showthread.php?p=5194#post5194).
http://www.divetraining.net/pictures/2010_jan_28/P1010035.jpg
Tj scootering mainline Ginnie on the Hollis DPV.
Contact Peter or TJ for a great deal on one today!
Despite the cold front coming in on top of us towards the end of the week, all the guys all did great, and everyone graduated their classes with flying colors!
http://www.divetraining.net/pictures/2010_jan_28/DSC05150.jpg
Intro Cave, Full Cave and Sidemount Class, Jan 2010.
A great week was had by all, and we can’t wait for the caves to right themselves :)
Check out the rest of the trip photos here (http://www.divetraining.net/pictures/2010_jan_28/)
For those new to Cave diving or the specifics on flooding of Caves here are some notes on flooding:
Most of the caves in Florida are SPRINGS, the water flows from deep within the aquifer out of them, out through the cave and caverns, through a river run (often called a slough), and then down to a river and on to the ocean. Florida's springs are the largest by volume in the world (they discharge more than 19 billion gallons of freshwater per day), feeding into and often supporting entire river systems. Most of the commonly dived caves in North Florida are located on the Suwanee or Santa Fe River. Peacock, Little River, Telford, Kitty are all located on the Suwanee River. Ginnie Springs and Jug Springs are located on the Santa Fe River.
A large amount of rain in Georgia can cause rivers, notably the Suwanee in this case, to flood, increase massively in volume, and cause the river to “bulge”. This increase in pressure puts pressure on the caves that are located along the river; as the river increases in height, the water floods into all available spaces, including the cave openings…..and this higher pressure presses against the natural flow from the spring. If the river height increases enough, the river water “wins” and completely stops the flow from the cave, and can even push against it and force its way through the cave systems. This results in a siphon, water flowing in the reverse direction of the normal flow from a spring, and the caves filling with river water (the common expression for caves in this state is “blown”). River water is naturally tannic (due to the vegetation in and alongside the river), and much colder than spring water. How fast caves “blow” (become undiveable) depends on the normal flow in the cave, and how close the cave is to the river. In cave country Madison Springs is commonly the first to go, followed by Telford and then Little River.
There are many side effects of cave flooding, most notably (for cave divers) is as they start siphoning instead of springing, they become undivable. Diving WITH the flow of water into cave in a zero viz situation, is not a pleasant or a SAFE cave diving experience.
Often as the river rises, it brings new critters into the spring environment. Last week in Little River Joe and I saw some five foot surgeon fish prowling around the cavern zone, as well as some schools of massive bass.
Another bad effect of flooding is that most of the wildlife living down in the caverns and caves are killed off, and it can take several months after the river level subsides for them to recolonize.
In the overall scheme of things, cave floods are very much part of natural progression, and can be actually good for the caves sometimes. They nourish the cave systems, by starting animal life cycles again from scratch. They also affect the way the cave looks by erasing some signs of divers, covering up careless fin, hand or scooter marks.
In time, the caves clear again, it takes time and this process is often helped along by lots of local rainfall. Sand lies over most of the top of most North Florida cave recharge areas, and this sand filters the runoff rain and helps the aquifer to recharge with clear water to push against the intruding river water. As the river levels subside, the cave water increases in pressure and pushes out against the river water, restoring the normal flow from the caves.
This week was an entirely different matter. We headed to cave country with a bunch of divers: Lou, Brent and Cam for Intro Cave Course (http://www.scubadiver.cc/forums/showthread.php?t=1392); Matt, David and Frank for Full Cave (http://www.scubadiver.cc/forums/showthread.php?t=1388), and Jim (with Scott swimming along) for Sidemount Cave (http://www.scubadiver.cc/forums/showthread.php?t=1379), all eager to do some cave diving.
On Sunday we visited Cow Springs and Little River Springs, and at both the spring heads were 5-10 feet higher than the previous week, and the systems undiveable, due to an intrusion of tannic water.
Little River on Tuesday 19th Jan:
http://www.divetraining.net/pictures/2010_jan_19/DSC05129.jpg
Little River less than a week later:
http://www.divetraining.net/pictures/2010_jan_28/DSC05194.jpg
Water level is 10+ feet higher, there is a visible boil on the surface, and the cave is siphoning strongly with nasty cold river water.
On Monday we visited Peacock, and noticed water pouring in across the slough into P3. It was siphoning strongly, and the basin filling up fast.
http://www.divetraining.net/pictures/2010_jan_28/p3_monday2010.jpg
River water entering the run and basin of P3
We headed across the park to Orange Grove, where we had a very nice dive, visibility was 40 or so feet. That afternoon we moved to Peacock 1, but the tannic water had already made its way through Mainline, and through the majority of the Peanut Tunnel. The visibility in the system ranged from 1 foot to 10 feet, and the temperature was mid fifties.
We dived at Ginnie Springs for the remainder of the week, and conditions there were very good. Flow was the usual (quite strong!), and visibility in the cave was 60+ feet. The eye was a bit green looking, but cleared as you go through the cavern, but the river spilled over in the ear, and visibility there was close to zero. It was also very cold (50 something degrees :()
On Wednesday evening TJ and I tried out the new Hollis H-160 DPV / Underwater Scooter. She rides very smooth, and is very easy to manage and VERY fast.
Click here for more information on the Hollis H-160 DPV / Underwater Scooter (http://www.scubadiver.cc/forums/showthread.php?p=5194#post5194).
http://www.divetraining.net/pictures/2010_jan_28/P1010035.jpg
Tj scootering mainline Ginnie on the Hollis DPV.
Contact Peter or TJ for a great deal on one today!
Despite the cold front coming in on top of us towards the end of the week, all the guys all did great, and everyone graduated their classes with flying colors!
http://www.divetraining.net/pictures/2010_jan_28/DSC05150.jpg
Intro Cave, Full Cave and Sidemount Class, Jan 2010.
A great week was had by all, and we can’t wait for the caves to right themselves :)
Check out the rest of the trip photos here (http://www.divetraining.net/pictures/2010_jan_28/)
For those new to Cave diving or the specifics on flooding of Caves here are some notes on flooding:
Most of the caves in Florida are SPRINGS, the water flows from deep within the aquifer out of them, out through the cave and caverns, through a river run (often called a slough), and then down to a river and on to the ocean. Florida's springs are the largest by volume in the world (they discharge more than 19 billion gallons of freshwater per day), feeding into and often supporting entire river systems. Most of the commonly dived caves in North Florida are located on the Suwanee or Santa Fe River. Peacock, Little River, Telford, Kitty are all located on the Suwanee River. Ginnie Springs and Jug Springs are located on the Santa Fe River.
A large amount of rain in Georgia can cause rivers, notably the Suwanee in this case, to flood, increase massively in volume, and cause the river to “bulge”. This increase in pressure puts pressure on the caves that are located along the river; as the river increases in height, the water floods into all available spaces, including the cave openings…..and this higher pressure presses against the natural flow from the spring. If the river height increases enough, the river water “wins” and completely stops the flow from the cave, and can even push against it and force its way through the cave systems. This results in a siphon, water flowing in the reverse direction of the normal flow from a spring, and the caves filling with river water (the common expression for caves in this state is “blown”). River water is naturally tannic (due to the vegetation in and alongside the river), and much colder than spring water. How fast caves “blow” (become undiveable) depends on the normal flow in the cave, and how close the cave is to the river. In cave country Madison Springs is commonly the first to go, followed by Telford and then Little River.
There are many side effects of cave flooding, most notably (for cave divers) is as they start siphoning instead of springing, they become undivable. Diving WITH the flow of water into cave in a zero viz situation, is not a pleasant or a SAFE cave diving experience.
Often as the river rises, it brings new critters into the spring environment. Last week in Little River Joe and I saw some five foot surgeon fish prowling around the cavern zone, as well as some schools of massive bass.
Another bad effect of flooding is that most of the wildlife living down in the caverns and caves are killed off, and it can take several months after the river level subsides for them to recolonize.
In the overall scheme of things, cave floods are very much part of natural progression, and can be actually good for the caves sometimes. They nourish the cave systems, by starting animal life cycles again from scratch. They also affect the way the cave looks by erasing some signs of divers, covering up careless fin, hand or scooter marks.
In time, the caves clear again, it takes time and this process is often helped along by lots of local rainfall. Sand lies over most of the top of most North Florida cave recharge areas, and this sand filters the runoff rain and helps the aquifer to recharge with clear water to push against the intruding river water. As the river levels subside, the cave water increases in pressure and pushes out against the river water, restoring the normal flow from the caves.