Adequate safety precautions

After discussing the goal and safety issues with the facilities man, the plan was set:
The goal was to clear obstructions and pry open or even remove the mud gate
The first dive would be non-tethered and would be to evaluate and photograph the mud gate and determine what tools to bring on the subsequent tethered dive
On the second dive, I would wear a polypropylene rope tether and have a line tender
The tether would be secured on shore at a length that would limit my proximity to the mud gate opening- it would allow my hands to reach the area of differential pressure, but not allow my body to be sucked onto the opening
After opening the mud gate, the diver would exit the water while the impoundment drained
I geared up and then climbed down a ladder to get to the water's edge. Up close, the water still looked dark and murky and the scattered layer of foam on the surface gave it a pretty crappy look. Once I submerged, it turned out to have surprisingly good vis of about 10'! I was in my drysuit and the 64-degree water felt great!
Taking pictures along the way, a few fin kicks brought me down the sloped, mostly sandy bottom to the mud gate valve. There was a faint rumble of moving water. Large sheets of thick plastic were sucked into a slightly open corner of the gate. The plastic was also wrapped around the vertical shaft of the gate.
From the originalGate Valve
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