Caverns At Chankannab Park

[ERIC.K]

I recently dove at Chankannab park, Cozumel Mexico, nice easy dive in which we visited a group of caverns with several nice swim throughs, I had a couple of questions for anyone that might know the answers. First, How does a cave diver see when fresh water meets saltwater, at times my vision was completly distorted, if a cave diver entered a cave where fresh water entered into a saltwater cave would his vision eventually clear, has anyone been in a situation where that salt-freshwater destortion didn't clear? second, anyone dove the caverns i'm speaking of and if so how far do they go back, do these caverns become a series of caves? lastly after swimming out of the cavern, I noticed a layer of brown colored water filtering out of the caverns that I hoped wasn't pollution. Thank heavens for my environment sealed first stage.

 

[Meng_Tze]

I recently dove at Chankannab park, Cozumel Mexico, nice easy dive in which we visited a group of caverns with several nice swim throughs, I had a couple of questions for anyone that might know the answers. First, How does a cave diver see when fresh water meets saltwater, at times my vision was completly distorted, if a cave diver entered a cave where fresh water entered into a saltwater cave would his vision eventually clear, has anyone been in a situation where that salt-freshwater destortion didn't clear? second, anyone dove the caverns i'm speaking of and if so how far do they go back, do these caverns become a series of caves? lastly after swimming out of the cavern, I noticed a layer of brown colored water filtering out of the caverns that I hoped wasn't pollution. Thank heavens for my environment sealed first stage.

I have not been there (desperately want to go....), but here is my take:

that transition zone (halocline) of blurred vision is normal. It is where salt and fresh water mix. Below and above it vision is clear.

Once you loose sight of daylight, you are in a cave. So it really does not matter how far in you are. When you can not see daylight anymore, technically you are in a cave and have passed the cavern zone as they call it.

That brown water could be many things, most likely some tannic intrusion. This comes from rotting leaves, trees etc. It could also be mud seeping in, or indeed pollution. Only way to know is to fins the source. If you would investigate and find rusting barrels with stuff oozing out, yeah it probably is pollution...

 

[MtnDiver]

We did the swim through in the area you are talking about. Talking with our guide, Victor Zapata, who runs one of the dive "shops" in the park, he said that his grandfather explored the caves back in several miles.

How is the park these days? We dove it about a month before the hurricane slammed Cozumel. Just wondering if there was much left of the underwater part of the park.

 

[loosebits]

If the team fans out instead of swimming single file, the halocline won't bother you. It's only when you're in the wake of another diver who has gone through it that it causes a problem.

 

[ERIC.K]

First, I wanted to start by saying I have fun diving in a swimming pool. Mtndiver, Chankannab appears to be making great strides to recover. The Christ statue remains, The Virgin Mary statue is still there, apparently the park had a couple of fiberglass Mayan-Aztec like statues that Alberto, our dive guide, says that God only knows where they went. There was an anchor there as well but Alberto states that it is buried under several feet of sand. Chankannab Park really from what I remember was simple coral heads that you swim to and from, seen several morays, many stingrays, couple of lobsters, I always loved diving the "no-brainer" Chankannab because I can thumb my nose at all the snoklers at the surface, my very own nana-nana-boo-boo. I was very pleased by the condition of the park, I was holding my breath prior to our arrival though. You can see the park needs some work, but I was pleasantly surprised

 

[Mike Edmonston]

lastly after swimming out of the cavern, I noticed a layer of brown colored water filtering out of the caverns that I hoped wasn't pollution. Thank heavens for my environment sealed first stage.

That layer you are referring to was most likely a Hydrogen sulfide layer. nothing to concern yourself about. it's not pollution, it's bacteria feeding on decomposing vegetation. I have dove in some caves in Abaco where the Sulfide layer is 22ft thick and bright red. it reduces your vis to 2 or 3 INCHES!! very eerie dive. it also makes your lips tingle and you can smell it underwater through your mask. :huh:

Have fun

Cheers

Mike