GreggS
Contributor
Mods, if this better suited elsewhere, please move.
My wife and I went to one of our local quarries yesterday for our first dive of the season. It is one of three quarries belonging to the NC PDRA (NC Piedmont Diving and Rescue Association) to which we are members and this quarry is the closest one to us. I had read on their website late last year when we paid our annual dues that they had installed a system in this quarry that is supposed to regulate both visibility and temps. I really didn't know what to expect but wanted to check it out.
Wow, were we surprised and very pleased. The system involves a series of aerators placed in 4 or 5 locations that keeps the water moving. Previously, although that particular quarry drops to around 65 ffw in "the pit", we would usually not be able to go below 40 feet due to the extreme thermocline around 40 feet as well as there being a defined light line at that depth. And when I say a defined light line, I mean you could put it at eye level and see light at the top of your mask and the bottom of your mask would be totally dark. You could not see more than 1 foot even with a strong light.
Yesterday, we went to 62 feet in the pit. Although it was a little dark due to it being a mostly cloudy day, I could still see without my light. I have attached an image of my dive log from last year on June 2 and my dive log from yesterday. Last year, I did not go below 40 feet and the temperature varied with my depth. As I've already said, I went to 62 feet yesterday.
Take a look at the temperature line on both graphs. And, yes, that is correct.
They are going to install this system at one of the other quarries this fall. That quarry goes to almost 100 feet, but I've never been deeper than about 65 ffw due to the cold. I think they'll do the other quarry next year.
My wife and I went to one of our local quarries yesterday for our first dive of the season. It is one of three quarries belonging to the NC PDRA (NC Piedmont Diving and Rescue Association) to which we are members and this quarry is the closest one to us. I had read on their website late last year when we paid our annual dues that they had installed a system in this quarry that is supposed to regulate both visibility and temps. I really didn't know what to expect but wanted to check it out.
Wow, were we surprised and very pleased. The system involves a series of aerators placed in 4 or 5 locations that keeps the water moving. Previously, although that particular quarry drops to around 65 ffw in "the pit", we would usually not be able to go below 40 feet due to the extreme thermocline around 40 feet as well as there being a defined light line at that depth. And when I say a defined light line, I mean you could put it at eye level and see light at the top of your mask and the bottom of your mask would be totally dark. You could not see more than 1 foot even with a strong light.
Yesterday, we went to 62 feet in the pit. Although it was a little dark due to it being a mostly cloudy day, I could still see without my light. I have attached an image of my dive log from last year on June 2 and my dive log from yesterday. Last year, I did not go below 40 feet and the temperature varied with my depth. As I've already said, I went to 62 feet yesterday.
Take a look at the temperature line on both graphs. And, yes, that is correct.
They are going to install this system at one of the other quarries this fall. That quarry goes to almost 100 feet, but I've never been deeper than about 65 ffw due to the cold. I think they'll do the other quarry next year.