0 viz?

[ZenSquirrel]

When you tell somebody that you had 0 viz, does that really mean that you could not see your guages if you stuck them against your mask?

Just wondering b/c I keep seeing stories where "the viz dropped to 0" or "we were diving in 0 viz" and I'm trying to figure out exactally how murky that is. I've been diving in 3-5 ft viz where you hit patches of .5-1 foot viz. Is it possible to have water so mucky that you can't see your guages?

 

[Don Burke]

When you tell somebody that you had 0 viz, does that really mean that you could not see your guages if you stuck them against your mask?

Just wondering b/c I keep seeing stories where "the viz dropped to 0" or "we were diving in 0 viz" and I'm trying to figure out exactally how murky that is. I've been diving in 3-5 ft viz where you hit patches of .5-1 foot viz. Is it possible to have water so mucky that you can't see your guages?

I've been in water where I couldn't read my guages.

Somewhere in my pile of books is the story of an operation where the salvage divers could put a big lamp up against their faceplates and not be able to tell if it was turned on. I'd have to see that for myself.

 

[ScubaStan]

I dive regularly off the coast of Ventura, Malibu, Goleta, and Santa Barbara. Many times I have run into 0 viz. I couldn't see my guages, hand, or anything else UNLESS it was directly pressed up against my mask in front of my eyes. I have even been in a situation where in following the bottom to prevent confusion with up and down, I have run my face into the sand.

Yes, sometimes even divers have to run on instruments. It isn't something I do all the time, but good to know how to do so. When I get tired of it, I just head for the surface (if it expected to bet better) but I couldn't imagine what it would be like in any type of overhead environment with 0 viz.

 

[Walter]

There's zero viz and there's black water. Zero viz is when you cannot see your hand placed against your mask. Black water is when you can't see a light placed against your mask. I've only seen black water twice. I've encountered zero viz many times. Often when diving for fossils, the viz is measured in inches.

 

[matt_unique]

I was following the bottom in a lake once and did not see an upslope in the topography until my mask mashed into the mud. Ha ha - hello!

I have honestly never seen blackwater as previously described. That would be crazy to put your light to your mask and not be able to see whether it was on...It would obviously be a situation you would want to remedy asap. Always gotta know what your stores are.

--Matt

 

[Allen42]

Seriously? There is something that has a consistency so opaque as to not have a very bright light penetrate less than one inch? I want to believe, but that sounds like an unswimmable consistency.

Or is there another property of black water that absorbs light?

Either way... doesn't sound fun.

 

[Walter]

I don't know why it happens, I'm just glad I've only encountered it twice. Both times it was in a small area so I was able to swim out of it without surfaceing. The first time was in a quarry in NC. The second time was diving with NetDoc at Venice Beach. I believe that was his first ever dive at Venice.

 

[Ber Rabbit]

My friend (and instructor) has done S&R dives in farm ponds where the vis was so bad they taped a plastic bag of tap water to their gauges then pressed that against their mask so they could read them.
Ber :lilbunny:

 

[JustAddWater]

I've experienced close to 0 viz. It was more like 6 inches. I've never encountered black water. It sounds like a pretty strange occurance.
Walter, what was the depth when you experienced it?

 

[Walter]

Venice was about 15 ft. I'll have to check my log for the info on the NC dive.