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Almost an Open Water Class today

This dive season has been challenging at Millbrook this year. As usual the water was it's normal cold back in April in the 40 degree range but it was pretty clear. May was about the same the water temp was not rising like it normally would due the rain, we have had a good bit this year.

From observation, but not by any scientific measurements, the picture you see here is the entrance to Beach one. There is a wooden platform with 5 or 6 steps.  Last fall the water level was so low only the last 2 steps were under water.  With this weeks past rain the entire platform is underwater and is about 18+ inches above the deck.  So that is 7 inches for each step plus the 18+ on top of the deck, that would put the total rise around 30 inches.  That is a lot of water considering the size of the quarry.

Somewhere between May and June a cloud of turbidity formed. This is not unusual there is always a layer of turbidity normally just above the thermocline and it is a few inches to foot high in the water column.  The density would vary from place to place in the quarry but never really dense.

When I was diving there in June, entering the water I notice something was different the surface water was very warm, warm like you would have in September around 70 degrees.  Once we descended I found out why. The turbidity layer started around 12 ft and went about 25 ft and it was like looking though pea soup.  Its density was such that sunlight could not penetrate that deep, it was heating up the surface water.

The end of June there was some more rain and divers I know where at the quarry they said the turbidity had seem to thin out. it was still not great but better.

Move a head to today July 13.  We had several inches of rain this week. Surface was warm, the descent had good viz down to 12 feet. Then it got ugly!  Taking my two open water students to about 20 ft holding a line I could not see them. The both grabbed my hand and pulled up, up we went.  They express their concerns about diving in this. This was if you could picture a green cloud in the water. I told there there was a good chance that if we got below it on the training platform it would be clear. I explained my past months experience. PADI standards say you can not leave a student unattended in the water. I explained that if they were willing we could go together in physical contact down line to the platform and see what the conditions looked like. If it was clear we could do the dive. They agreed.

Down we went. I have an Aeris AI dive computer, it is clipped to the chest D-ring on my BCD. It is always about 6-8 inches from my face. The digital display has reasonable size numbers and is easy to read. 16 feet was the last depth I could see. After that I could not see the computer the turbidity was so thick.  What was more disturbing as we continue down I swear the cloud turned from green to red.  That could be a problem. 

After what I thought was red, it became black and we where on the platform. Once my eyes adjusted it was clearer, 3-5 feet of viz, we where below the cloud but the only thing of note I could see was the phosphors glow of our three compasses, to read my computer I had to press the light button. 

Dive over, up we went.  I still swear the lower few feet of the cloud is red and that should not be. 

My divers where troopers, we are working on a plan  to go to Lake Rawlings.

Have to see what happens with the quarry. It may have too much water in it. Throwing off the ecosystem.  I will keep you posted. May just have to finish out the dive season at Rawlings.  It is just such a long ride.